cilinders 1 - 3 not working

Hi all, new to this forum. 3 months ago I bought a 2002 996 targa with 175k km. I drove it for about 2000km. Than on a 30km drive home the engine started to sound more and more rough, more and more vibrations. When the rpm got below 3000 I lost all power (engine did not die), and with full throttle it slowly picked up speed until it reached 2700 to 3000 rmp when all power returned and the car lept forward in a jerk. Tried to make it home, but after 10km of this it finally stalled and did not want to start again. During the last 10km of running, check engine light came on, fuel light came on, abs errors, pcm error all came and went. Towed the car home and put a simple obd reader on the car. I was greeted with the following codes: P0343: CMP sensor A bank 1 -high input P0303: cilinder 3 misfire P0302: cilinder 2 misfire P0301: cilinder 1 misfire P0300: multiple misfire detecte P1325 P1341 At this point I called the Indy where I bought the car from and they said to replace the camshaft position sensor. Did not think too much of it, so I went ahead and replaced it. Cleared the codes with the simple obd reader, but the rough running remains. At this point only code P0343 is coming back. Putting a temperature reading on all cilinder exhausts shows that cilinders 1,2 and 3 remain cold, cilinders 4 to 6 warm up. I do have a fuel smell, so I assume cilinders 1-3 are getting fuel. Compression test on cilinders 1 - 3 gives between 126 and 128 PSI Took out coil of cilinder 3 and connected spare spark plug, it spraked but it was yellow. Used camera to inspect the cilinders, I am no expert what so ever, but my amateur opinion is that I did not see lines on the cilinder walls, and no damage to piston ( not hitting valves or anything) Only thing to note was that cilinder 3 had a lot of oil in it ( a puddle of 1 or 2 mm high), so I removed fuse for fuel pump and ignition, and with spark plug removed, ran the starter so it could pump out the oil. After which I put back the fuses and tried starting again, still no joy on cilinders 1-3. I replace coils and plugs on cilinders 1 - 3. Still not firing. (I have not yet checked spark again to see if it is nice and blue, nor did I test on all 3 cilinders to ensure I have spark) With the cmp on bank 1 disconnected, the engine behaves the same as when connected. Question 1: So if DME decides not to use cilinders 1-3, why do I still get spark and why do still smell fuel? I would think that if DME decides not to use a cilinder that it would not send spark signal and not trigger injectors? Question 2: I read that without cmp on bank1 the engine should still fire up (on all 6)? I did some google-fu and found in the workshop manual to check signal wire from DME to sensor for short to B+. Now I do not understand what short to B+ means, nor do I have special tool 9637. So I started measuring. Below you can find all my results, but short version is that all measurements I took for wires to and from cmp on bank 1 are the exact same as the measurements for bank 2. So I do not understand why cmp bank 1 is throwing error and cmp bank 2 is not. Question 3: Can someone explain me between which points I need to make a measurement. And what should be disconnected before making the measurement? (note I did a lot of measurements described further in this post) Question 4: the wiring diagrams say that the supply voltage should be 5V, but I measure 11V? Measurements I took on the cable end that goes into the CMP on bank 1: Let's call wire to DME gnd line A Let's call wire to DME output/signal line B Let's call wire to DME supply line C A - B: 10,7V and 49k ohm A - C: 11.2V and 70 ohm B - C: 0.4V and 42k ohm A to chassis: 0V and 0.2 ohm B to chassis: 10.8V and 42k ohm C to chassis: 11.2V and 70 ohm Now if I disconnect pin C12 (cmp bank 1 signal) from connector to DME, than I measure no voltage between wire in plug to sensor and chassis. Which leads me to believe that C12 is supplying voltage but 0.4V less than the DME supply wire to the sensor. Now for the interesting bit, I have almost identical measurements for CMP on bank 2. Question 5: Why is the computer still reporting high signal on cmp bank1 even though I get same measurements comparing CMP on both banks. Another observation I made is that found very small oil leak at the bottom of the engine where it connects to the gearbox. Also the two connections between left and right air intake are oily. And if I open oil reservoir cap, there seems to be some negative pressure. ( I have ordered a second oil cap so I can drill a hole and add vacuum pressure meter to see if AOS might be bad) Will report measurements here once I get those parts. Question 6: Could the above indicate a bad AOS? It was replaced already in 2017, and reading about AOS does indicate I should consider replacing every 6 or 7 years? Question 7: IF it theory is bad AOS, how does that explain only cilinders 1-3 not working. Question 8: What parts of the engine are dedicated to one cilinder bank? So that I can test by swapping or measuring those components to try and understand why bank 1 is not happy? Additional info that might or might not be related: AOS, IMS and RMS where replaced around 2017. It started raining on the drive home, first time I drove it in the rain. Before driving home, the car was parked on a hill side. Front right wheel was highest, rear left was lowest. No smoke as far as I could tell. I was almost out of gas, so I thought it might be running out of fuel during the rough running, so I fueled up, but rough running remained. On the last drive before the return home drive, at points in time I thought I heard ticking (for lack of a getter word) When trying the start the car when towed home (and before doing any work) there was again a subtle metal ticking that went away after a few seconds of idling. After replacing cam shaft position sensor, coils and plugs on bank 1 (cilinders 1-3), this ticking is completely gone.

Forgot to add that I removed and check the two variocam actuators as well. The left one (timing?) was fine, the right one (lift adjustment?) was stuck. A healthy dose of brake cleaner and a lot of testing with a 12 V battery got it loose again and working fine even when putting pressure on it. Put it back, no change whatsoever.

I see that you said you are getting a fuel smell, but if all three cylinders on bank 1 are not producing power, I would check the ground point for the fuel injectors on that side of the engine. IIRC the ground point is located on the end of the head near the mount for the crank position sensor plug. It is a ring connector attach� to the head with a 6mm bolt (10mm head). Hope this helps. Mark

I�ll suggest that you should find someone with a Porsche specific scan tool. A Durametric or PIWIS will give more info concerning cam deviation, etc.

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no ground for the fuel rail seems like a very reasonable explanation, however I am not finding any connections to ground from the rail. Unless the ground is achieved via the bolts that mount the fuel rail to the engine? I did a quick measurement and I get 0.3 ohm from fuel rail to alternator, so I think we can assume ground for fuel rail is good? (I was hoping it would not be as this would have been easy fix)

I hope to buy a durametric kit tomorrow so I can go and test. If anyone has an answer to any of my above questions that would be cool. I am trying to learn as much as I can about this car as I hope to enjoy it for many years to come Thanks for the replies! Much appreciated. J

The fuel rail is not grounded. The fuel injecors what is grounded. This harness is what was explained above.

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Oh, ok, I misunderstood. I know about the ground on passenger side, will look for the ground on driver side and test. Thanks!

Its under the aos, on the firewall side of the head. U have to look up from under the car. Even if it looks connected i would remove the bolt, clean and reinstall

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Ok, with that help I did find it. Removed the bolt and found the ground connection. It was looking dirty, so I cleaned it so it shines, bolted back on. So now the P0343 code seems to be gone. But still cilinders 1-3 do not fire up. Before the car would keep idling on cilinders 4-6, but now it only idles for a few seconds and then dies. So progress as the code seems to have gone, but now I cannot do a vacuum measurement with my modified oil cap and vacuum gauge in an attempt to see if AOS is still good. I read a post somewhere that 4 to 6 inches of H2O is good, 8 or higher might indicate a bad AOS. Speaking of AOS, I have a genuine new one. But could not get to it from the top of the engine, but now that I looked at it from under it (I do have a lift) seems like I stand a chance to remove it from under the car? (this is a 3.6 so it is slightly different compared to the 3.4). I'm still trying to buy a duratech tomorrow so I can do a better ECU reading than my current cheapass OBDII bluetooth reader. Thanks for the help, I'm sure with the combined knowledge and experience from the folks here I will find a way to make the engine happy once more. J

One other thing I thought of is the fuel pressure sensor. Since it seems fuel first goes to first to bank 2 (cyl 4-6) and then through hose to bank 1 (cyl 1-3), any chance that too low a pressure can cause not enough pressure to remain on the rail on bank 1? Or am I overthinking it from troubleshooting this for too long

Is it possible the timing sprocket on bank one cam shaft has come loose and put bank one out of time ?

Im starting to suspect a timing issue too.....we need to see some telemetry from the durametric when u get it. Cam timing is what we need.

Ok, I'll focus on getting the durametric first. Do you guys know of any good documentation sources to teach me how to properly use it or is it pretty self-explanatory?

I do remember hearing clicking noise (metal on metal), nothing too loud, only when I drove with the window open was it noticable. Does that point towards cam out of sync?

You can download a user manual from the website and the software. It's pretty straightforward. You are basically buying the connector, unless things have changed the last few years.

'Short to B+' means a short circuit to the positive terminal of the battery irrespective of the key position in the ignition lock, I.e. Live at all times. Your measuring 11V at sensors that should show 5V supply voltage does seem to coincide witht that! Fuel smell can only mean injectors fire but fuel is not ignited which a yellow instead of blueish-white spark is indicative of too. Fuel pressure is equal in both rails. No way that the injectors inject so much fuel on bank2 that the pressure drops in the rail in bank one as all injectors fire sequentially in the firing order which alternates between both banks. So if anything wrong with fuel flow from the pump pressure on both banks would be low. I'd look into proper grounds and steady power supply to all coils, sensors and injectors (in that order)

Cylinders 1-3 share a common ground wire (brown) to ground point 11. Check for continuity between one of the brown wires at the coil pack to the engine case to verify ground for the coil pack on that side of the engine.

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I will measure again now that the ground point 11 has been cleaned up. Funny thing is that cam shaft sensor on bank 2 had exact same readings but was not throwing errors. That makes sense. Will do, thanks for the support.

Unfortunately, I will only be able to go get the durametric after the weekend. Verifying timing will need to wait a few days. I'll report back when I got it and checked the timing. Enjoy the weekend.

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if you suspect the timing, you can remove the cam plugs, rotate the engine to TDC and check for alignment. On the 3.6 the two camshaft grooves should align.

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meirschwartz has a point. Since you can�t keep the engine running the Durametric won�t be much help.

The Durametric can report values without the engine running.

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This^ And pull and check your oil filter for any debris that could yield more clues. You mention a new oil leak at the trans so it could be the bearing on it's way out causing the chain to jump and the seal to fail. The IMSB side drives the chain to bank 1 where your problem is so this makes sense. I'd try to figure it out without starting the engine again.

The durametric is pretty straight forward, but its probably slightly harder to use if you've never seen it on a running engine... FWIW, if you have a bore scope go in through the throttle body and check the left intake for pools of oil. Thats what I had after my AOS failed and hydro/cracked 2 cylinders on the left bank. There is no expected life of a AOS they can fail at 100K or 10K or 1K.. Crap design..

Ok, got the durametric and used it to scan for codes first. This is what came back: first durametric fault scan So I cleared the codes and tried again, this time, only my good old friend P0343 came back. Which is probably why I do not get any readings from bank 1 when trying to see timing when running the engine (which seems like I should no longer do?) Trying to measure cam timing. So at this point I am kind of thinking to drop the engine. This would cost me time and a fresh set of oil and coolant. However it seems draining the oil for inspection should be high up my list of todo's anyway. So unless someone has a good reason why I should not drop it, that will be the plan for the coming days. When dropped I plan to check the following, and do please chime in on what else to check while the engine is out inspect the oil for any debris plan to replace oil drain plug with a magnetic one check timing physically Should I check chain tensioners and guides? I assume the only way to check is to disassemble to the point where I can physically see them? Since I have a brand new AOS, I might as well replace it I have a smoke device to test for any vacuum leaks remove all black tape of all electrical wires and inspect carefully for any damaged insulation ? Is there a way to test oil pump, water pump, scavenge pumps without removing them? Should I remove them for inspection? ? IMS and RMS where done 7 years ago, can these fail, how do I check they are still good? thoroughly clean ground points, polish connectors, use conductive paste when re-attaching grounds. Is there a way I can test the injectors? What else should I do or avoid doing? What reading should I do before starting this job? I consider myself to have medium mechanic skills. I am planning to buy Jack Raby's M9x assembly dvd and book series. I have the workshop manuals, and the Bentley Publishers P911 service manual is on its way ( however still a month out).

A bad ground, common to All those items faulted in your first picture could also be the cause. Perhaps someone with access to the wiring diagrams (in the Bentley manual) could answer tou that question. Dropping oil pan nd inspecting oil filter would be my first step.

I would try turning the motor over by hand to see if you feel any resistance caused by a valve touching a piston. Then I would pull the cam plugs for bank one, turn the engine to TDC and check to see if the slots ion the cams are in line with the split line between the head and the cam cover as Mierschwartz suggested. These can be performed without dropping the engine. It still looks to me like it could be an electrical issue. From my review of the wiring diagram, check the black wire which is common to all six injectors. Check fro continuity between the black wire on the bank 1 injectors and the bank 2 injectors Good luck with it

Have you checked your exhaust flow out of bank 1, if you have a broken up catalyst internally blocking flow on that bank, the bank injectors will stop working and log a injector wiring fault along catalyst oxygen faults, be easy to remove bank one catalyst and run the engine.

https://rennlist.com/forums/996-turb...ensor-1-a.html Here is an earlier thread with a similar P0343 Fault .

Ok, so I checked if the cams on bank 1 are still in alignment and it seems they are not. Could you please confirm this for me with the pictures below: Putting engine at TDC: engine at TDC Checking the cams on bank 1 and they do not seem to align: cams at bank1 Closeup of bottom cam: bottom cam position closeup Close up of top cam bank 1: close up of top cam Does this indeed indicate camshafts of bank 1 are out of position? If yes, engine out to verify what caused this? What could have caused this? bolts fixing sprocket in place coming loose? -> if so what else was not torqued to spec chain tensioners failing ...? Could this cause the P0343 error? I appreciate all the help you guys are providing so far!

I think the easiest way to check cam alignment would be to turn drive pulley clockwise until pear shaped cutout in pulley is centered over hole in engine case about at the 11:00 position. Then take a 5/16 th�s drill bit and lock into that bored hole. The cam slots should line up with joint between head and cam cover. I�m fairly sure the hall sensor gets its voltage via the MAF sensor. That should be 5 volts. you can check for voltage at the MAFs A2 pin by turning ignition to run position.

I will go and check if the notch might not be the right way to put engine at TDC, will check if the pear shaped hole aligns as well, as shown on picture 1 here: https://www.pelicanparts.com/techart...ain_Repair.htm Will report back in a few hours. Thanks, J

Yeah, I confirm, when the notch lines up with the mark, the pear-shape hole also lines up with the hole to lock the position. So I am pretty sure cam is indeed out of alignment.

There are some good U-tube videos from Flat6/LN Engineering/Rennvision on the cam timing stuff..

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It happened to me on bank 2. Timing chain skipped a tooth and had bad misfires on cyl 4,5,6. Thankfully I was able to pull the oil scavenge pump on bank 2, loosen the bolts in the sprocket and rotate the exhaust cam back into place. Might be possible to do on bank 1 with the engine in the car, but not entirely sure how accessible the bank 1 scavenge pump is being at the front of the engine up against the firewall.

Would it not be prudent for me to drop the engine so I can find out why timing is misaligned now? I would prefer to find out why timing is out of whack first so I then know how to properly fix it. For example if timing skipped a tooth, how would that be possible, aka how can I prevent this from happening again. I'm kinda nervous that this happened so I want to make sure I figure out the why so I can come up with a good permanent fix. Thanks, J

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Yeah I think if you have the ability to drop the engine that is preferable. I didn�t have the facilities to do that, so my method was a quick fix.

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first, based on your pictures you are definitely out of timing. if you have the means, drop the engine. the time it will take you to drop it is less than the time (and frustration) it will take you to fiddle with the inspection and fix, with the engine still in the car. reason for skipping timing can be related to bad tensioners (the tensioners were revised) and worn pads, or a broken camshaft bolt (another part that was revised). before you continue, turn the engine by hand, and see if the camshafts are spinning. that will help you rule out a broken bolt or even a broken chain. good luck. Edit. here is a link to the timing procedure, showing the bolt that needs to be replaced. You Tube

I don’t think it is possible to re-time a 996.2 with the 3 chain engine without pulling the engine. The procedure required to tighten the bolt holding the vane cell adjuster on the intake cam is much more difficult that adjusting the chain on the exhaust cam on 5 chain engine. I believe you will be able to accomplish this much faster and easier if you drop the engine and have good access rather than trying to do it with the engine in the car. Have you determined why it is out of alignment? My guess is an issue with the IMS bearing or the cam chain tensioners has allowed the chain to jump on the IMS sprocket. I would also do a leak down check to determine if you have any bent valves on that bank.

I have not determined what the cause of the out of time issue is. IMS was done in 2017, however the invoice does not indicate what replacement IMS was used. I probably should call the firm and ask. And I assume that in 2017 they would know to replace IMS with a permanent fix IMS type. I'm doing research on how to determine what caused the out of time issue, starting with checking if the cams move at all when rotating crank. I definitely want to figure out what caused the out of time and not just re-time without knowing root cause. I do notice small oil leak at the bottom of where engine is connected to transmission, which was covered up by a bead of some kind of silicone on the edge between engine and transmission, I'll post a picture later. So I wonder if IMS or RMS is weeping, or if it will come from the transmission...

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most likely it's the RMS or the IMS cover. the transmission is not known to leak (not from the input shaft in particular). here are some pictures I took when I removed my engine and disconnected the transmission. to put things in context, I'm the second owner of the car, purchased with 34k miles. I do not have any service records, but according to CarFax, it was services at the dealership. someone thought it would be a good idea to stop the leaking IMS cover.

It does seem your bank 1 is way off in cam timing on both cams. Given that it was running when you first bought it and now is no longer running, it would be good to drop that engine and figure out why it died like that. Once you get the engine off, the cam cover off, it might be very obvious, or not. The engine out of the car is about the only way to get that back in time. Good luck.

If you have an invoice the price for the IMS bearing that was installed will tell you a lot about which was used. the permanent IMS Solution from LN is about $1800 for the bearing. The retrofit is about $800 and is a 6 yr/75K bearing. Some of the roller bearings are about $600. Based on the photos of the cam positions it looks to have definitely jumped time and it looks to me like the chain not only skipped on the IMS sprocket but also between the intake and exhaust cams. Once the engine is out turn the crank and watch the cams. One possibility is the cam sprocket for bank 1 on the IMS has slipped on the IMS Shaft. If bank 2 is still in time that would eliminate that the IMS chain has jumped on the crank. Pull tie IMS flange off and check the IMS bearing. If it has failed (usually the cage between the ***** breaks) then the engine needs to come apart to clean out all the debris so that is does not get in the main and rod bearings and damage the crankshaft. Good luck with you investigation and the repairs. Mark

Because you see oil between the trans and engine plus the timing being out, your best best it to drop the engine so you can get a thorough look at things. The leaks alone are worth investigating. The engine comes out relatively easily once you get all of the cross members and panels etc out of the way. Of course, assuming the engine skipped time for a reason that can be easily fixed without splitting the case (failed cam bolts, failed tensioner vs a stretched chain or worn guides) there will be the� while you are in there� items. First things first, drop the motor and see why timing jumped. Go from there.

If you don't find a broken timing chain causing the cam timing to be off, you had better assume the IMS sprocket has slipped on the shaft... This is a fault that has been seen quite a bit and will require you to have the IMS repaired. LN does a pinning procedure to the sprockets to ensue they do not slip on the shaft, they are just press fit on the shaft and can sometimes slip if they are stressed to much like say if something hard goes into the scavenge pump and it tries to seize.. If you don't find the root cause I would condemn the IMS for slipped sprocket.. I have seen people just assume it is an unsolved mystery and just repair what they can find only to put it all back together and have it jump time again and bend all the valves due to IMS sprocket slip...

Checked the invoice for the IMS bearing replacement and is shows as a 399Euro "m96 IMS bearing single row" -> This was 6 years and 32 000 km ago. Does look like I might need to install the LN Engineering kit. I'll post picture once engine is out before doing any work. Further inspection of the invoices shows this in 2018: 4 camshaft plugs 2 alu o ring chain tensioner 1 camshaft lid 1 scavenge oil pump 1 camshaft sprocket 1 camshaft pulley central bolt 997 oil pressure valve bunch of o-rings for various parts So someone has definitely been in there before. Started removal of the engine, once it is out I will take extensive pictures and post here before doing anything. Seems like there is a lot of experience out here willing to help me do things right, which I appreciate a lot! Bentley's Service Manuals has arrive (4 weeks early, yay) that will help a ton, initial impression is that this book is golden. Thanks, J

I have that manual + the torque spec book that Flat6/Ln published. It's very handy had multiple things that didn't make it to the Bently. I also had the book 100 Porsche projects, which has a ton of good photos for removal and reinstall of the engine + a few tips on making some tasks easier by a bit. Oh and enough pics just for good reference when I ran in to something going back in I did not remember.. Both good books IMHO and were worth the $.. If you have to get deep enough to get the heads off,, stop and use a cylinder bore gage to check taper and oval , its fairly rare for a engine to be in spec after this amount of time.

So when I drained the oil, bad news greeted me. Pictures are worth more than a 1000 words is a saying in my area: metal flakes metal flakes So at this point in time, I do think the block needs to come apart. Pretty depressed at the moment as I only got to enjoy the car for 2 months. Tomorrow I will try to find some time to take pictures of the block and to separate the gearbox from the block so I can see the state of the IMS and RMS. I think that at this time the quickest way for me to enjoy the car again is to find a new engine and than take my time to determine what to do with this block. Rebuild myself using Jack Raby's engine rebuild series as a guide, or send it out to have it rebuilt. I'll keep you informed.

I'm sorry for you reading this and appreciate even more so that you've posted your findings. Good luck from here on!

One more observation: when turning crank manually intake cam does not move, exhaust cam does move. will take a look at he bolts connecting sprocket to intake cam, I expect to see carnage.

One more observation: the shavings appear to be non-ferro, a magnet is not attracting the shavings

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Since you have a three-chain engine, the only thing it can be is a broken cam sprocket, cam bolt, or broken cam.

It is possible that the bolt that hold the vane cell adjuster assembly on the intake cam has come loose or broken. The vane cell assembly also includes the intake cam sprocket. The intake cam on a three chain engine does not have cam sprocket bolts (see photo in post 39), only the long bolt through the center of the vane cell adjuster assembly. If it wasn’t cleaned good ( perfectly dry, no oil) prior to being tightened , the bolt could have come loose

OK, no more guessing. Open up the cam cover and you will know what broke.

Progress report: Removed scavenge pump on bank 1, the one connected to exhaust cam shaft: not ideal ... As soon as I took it out, the key connecting pump to camshaft fell out, and was missing some bits. no longer stock ... You can also see part of the sprocket around the key has broken off. very unhealthy oil scavenge pump. pump after weightloss program Next up: remove flywheel to take a look at the IMS and RMS, although I don't expect to see much there. (I have been proven to be utterly wrong many times before though) Check if I can remove what seems to be a plastic cap at the location of the intake camshaft, right above the oil pump. Since the intake one no longer rotates, I expect that the connection from sprocket to camshaft has been undone. So the current story the evidence is telling me, and I do invite all of you to tell your version of what you see, is that something broke loose somewhere and got stuck in the scavenge pump. This caused connection between pump and exhaust cam to break, and most likely that shock also broke the connection between intake cam sprocket and intake cam. Question: could this shock also have made the gear on the IMS shaft to move, as that is a press fit connection? -> only way to find out would be to completely disassemble the block? So that IMS shaft can be taken out and connection between IMS shaft and gear to be inspected? I started making some videos with my gopro, I am considering posting them on youtube so I can share my journey on video. Let me know if there is interest in that. Cheers, J

This is not the first time that a scavenge oil pump froze up due to foreign objects. I expect to see bent valves on that bank.

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Agree with yelcab , when cam stops turning in sync with pistons, valves hit pistons and bend/break in an interference type engine like our 996. Crank/rods can also be damaged. I know this is not what you want to hear, but it needs to be said for all those that might do the same, as you're not the only one. As many most people do the same and drive till it dies ... This is wrong from a mechanical/economical point of view for a 996. If you stopped driving at first sign of trouble, probably would have $aved valves from hitting pistons and maybe the bent rods you probably have now along with possible crank damage, and more, etc. All very very costly parts for this extremely expensive 996 engine that probably might have been saved for a rebuild if you listened to your engine and stopped driving,, This was your red flag to stop immediately and get towed v "When the rpm got below 3000 I lost all power (engine did not die), and with full throttle it slowly picked up speed until it reached 2700 to 3000 rmp when all power returned and the car lept forward in a jerk." "During the last 10km of running, check engine light came on, fuel light came on, abs errors, pcm error all came and went." What I don't understand is, you seem like a mechanically inclined type, so why not get a tow, knowing the possibilities if you continue...? And its not like you just drove on for a moment, you pushed on for 10km knowing something major wrong was going on inside your engine... "Tried to make it home, but after 10km of this it finally stalled and did not want to start again." IMO, these 996 engines are so costly to fix, at the first sign of engine trouble that you don't understand fully, STOP driving immediately or pay the price. To be fair, at over 100k miles the engine would have needed a full rebuild as soon as this problem started, but if you stopped sooner than driving till it died, you would of had a less expensive rebuild with many more very expensive rebuildable core parts. now you have more costly options... Just my advice for those in a similar positions, take it or leave it.... jmo

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Yes, I'm interested in seeing those

100% what allcool says. Pull over and call a tow truck at the first sign of engine trouble that you don't fully understand. It sucks and ruins your day, but the alternative is often worse.

You will need to totally disassemble the engine regardless. It all needs to be cleaned to remove foreign debris. You also need to inspect and measure the crank, crank carrier and rods to see if any are reusable. Sorry to hear what you found. Good luck with it. I have a set of 3.6 rods and you are welcome to them form the shipping cost if they will help you. Send me a pm if you want them. Mark

Fully agree with everyone saying I should have parked the car and towed it. Pretty upset with myself that I chose to listen to the you-ll-be-fine voice instead. Currently debating whether to buy a new block and get going again or to revise this engine. Either way, I'll post additional discoveries I make here. And if I end up attempting a re-build, then I'll probably start a new thread to document my progress there. Big thanks to everyone that chimed in!