Help Please!!! Valve Lifters Replacement

Hi folks, I am a proud owner of a 2003 996. As much as I love my baby, I sometimes feel like I picked the wrong car. Having driven only 2500 miles since I bought it, I have spent more than $5000 on repairing her. May be the guy who buys it from me will be lucky since it looks like I bought it in the phase where the maintenance costs are high and I am fixing of all of them. I have been struggling with the check engine light turning for the same code P0306 for the last 6 months or so. Cylinder 6 is the issue. After a whole lot of diagnostics and replacing the coil pack, fuel injector, spark plug, wiring harness, and spending close to $3000, the CEL is still on. When my independent mechanic replaced the coil pack, it worked fine for a couple of hours and just by the time I thought I had dodged a bullet, there it was again. It worked almost identically after replacing the wiring harness. I stored the car for 5 months and brought it out last weekend. I drove 3 hours to Chicago and the next morning when I fired up the car, CEL came up again. Having done all this work and having spent a lot of $$$, I was puzzled when I took it back to my mechanic. It was the same code P0306 this time as well. Cylinder 6 it is !!! He took a couple of days and after having spoken to the Porsche rep, he thinks it is a $4200 repair. Valve lifters need to be replaced. To replace both sides for all 6 cylinders, the quote is $4200 ($2100 for parts and $2100 labor) If it is just one side (the side of cylinder 6) which is causing the problem now, it would be $2900. But then, if the other lifters go bad in the future, I would need to shell out another $2900 at that point. The car has 93,500 miles on it and I am planning to put it on sale sometime this fall (September or October) since I am going to be moving out of the country on business/work What would you guys do? Replace both sides spending $4200 or just replace one side for 2900 and hope that it lasts through the summer. Secondly, does the cost of replacing the valve lifters sound reasonable? Any cheaper options out there? Aftermarket parts, etc? Any helpful information is greatly appreciated. Disclaimer: I do not have any tools and the option of doing it myself is ruled out. Thank you guys for your help!

If its still running good and at that mileage i would run it until you leave and sell it cheap as a track build platform to somebody.

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Nope, it doesn't run fine. Misfiring cylinder 6. Vibrates heavily on idle.

It's not recommended by Porsche, but you could change just the one bad lifter. I was told by a Porsche dealer tech that changing all the lifters on the bank is a preventative measure. I know of one case where replacing only the one bad lifter had good results. Something to ponder anyway. I would also look for another indy and also research compatible lifters. I've read on here ( use search) where some model BMW lifters are identical to Porsche for much less cost. Maybe someone else can chime in on this. I think "the book" says this is an 11 hr job( one bank). Here, indys charge $70-90/hr where a dealer gets a whole lot more than that. I think your quote is excessive.

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Thanks Dennis, I am looking into alternatives right now. I dont mind changing all the lifters from one bank. I would kill myself if they had to do all of the work again in 6 months to change another lifter in the same bank costing me almost the same amount. But really unsure I should touch the lifters in the other bank. I will look in to compatible lifters. Reading on a similar incident at Pelican where the dealer took the same route on a guy who had the same problem. http://forums.pelicanparts.com/porsche-996-997-forum/370826-2002-996-lifter-problem-only-12k-miles.html Sounds like my Indy is charging me dealer rates. Their labor rates are 97 bucks an hour. But really reputed guys in Madison area.

There are compatible lifter for the exhaust side but the intake lifters on the VarioCamPlus are specialized. When Porsche went from VarioCam to VaricoCamPlus they changed the number (maybe the design) of the exhaust lifters (on the earlier design the intake and exhaust lifters were the same) and totally redesigned the intake lifters. AT that time Porsche stopped distributing the "old" exhaust lifters, offering only the new part number. But Porsche sourced the lifters from the same company that provided BMW lifters, and the "old" lifters are still available from many sources other than Porsche at significantly lower pricing. I discovered this when I was working on my engine and replaced all the lifters. To date no one has been able to tell me if the old and new exhaust lifters are really any different. For the intake lifters I don't know if there is another source of compatible lifters. If you want to learn more about the lifters and the differences in the two systems check out htis thread I did back in 2010 https://rennlist.com/forums/996-foru...-a-primer.html

Can you hear the valve banging? I'd get a second opinion. Sounds like this guy is throwing parts at the problem.

Was a compression test done in the first round of Diagnostics ?

I own shop, if he didnt fix it he should eat the money already spent, i do . What up with the garages screwing people over becuse they are too lazy to perform a correct diagnosis!! I would just replace the one lifter. Its likely you will not have another problem after that...

I had a bad lifter on cylinder 6 on my 04 C2 at around 45k miles. Repaired under CPO they replaced all lifters on that bank, both intake and exhaust, as specified by Porsche. Car now has 72K miles on her and runs just as strong as ever. Just my experience with it, yet luckily I had a CPO to cover the entire tab. Also have to say that the P-Car dealer precislely diagnosed the problem in under 20 minutes, they did not try the "diagnose through and parts replacement" method.

Targan... Last time i have had a serious problem with one of my Porsche (a few years ago) i realized something....GO TO DEALER...they will easily diagnose your problem then it will probably cost you $100.00 and then you will decide what to do. At that time my mechanic kept my Porsche at his garage for more then 4 days and never found the problem.... then like Silotwo the Dealer in less then 15 minutes found the problem and a few hours later the car was running just perfect. When the problem is a bad suspension or brakes that is an easy diagnostic otherwise just go to dealer and that will be money well spend.. just my 02 Good luck Robert

Observations........ I think your first bill was so high is due to the wiring harness .Not sure which one was replaced but they tend to be labor intensive .A bit unusal to require replacement -corrorsion-rodents or chaffing ? As far as the current dilema -from a repair perspective the engine is like 2- 3 cylinder motors .If the repair is to be carried out with the engine in the car there really is no economy of scale .They do one side and repeat steps on the other side .The point being that doing one bank should be ok . Parts cost -google partsgeek.com they have the parts and are competitively priced . As far as labor costs -don't know but I am sure he factors in tying up a lift and mechanic for a day .The lift is the money maker .Smaller shop might be an option .I would use Porsche book labor guidelines as a guage a fair price .

Dharn55, that's some detailed research you have done on the lifters. Thanks a ton. I did research and find out that Porsche redesigned their intake exhaust lifters in 2002. Also, one of the parts guys told me that I might have luck finding cheaper exhaust lifters but finding intake lifters for less than Porsche listed price might not be possible. So, did you use the older type of exhaust lifters on your car? Clickclickboom, I do not hear the valve banging but I do have heavy vibrations on idle. Dcdrechsel, I believe he did the compressions tests this time when I took it in. Nitrorocket, I had this talk with him the last time before he changed the wiring harness. Because, he had already changed coilpack and spark plug and stuff which was totally not necessary. He says it's the usual protocol. I am really pissed now that even the harness didn't need replacement. I wish all mechanics were like u . Silotwo, Porsche996, Really, the biggest take away from this is to just get the diagnosis done by the dealer. But I read on PelicanParts that one of the dealers screwed up just like this going the same route as my Indy. Guess it depends on how good the dealer is as well. dcdrechsel, I am not sure whether he is going to drop the engine or do it with the engine in the car. I think it's a no brainier to go for 1 bank only now. I will look up partsgeek.com. Thanks! Again, thank u guys for all ur inputs. Any other cost saving tips are greatly appreciated.

There's a lot of other parts that are needed besides the lifters. Gaskets. seals. O rings and such. I always get the best price along with personalized and knowledgeable service from Sunset Porsche when buying parts. They will fix you up with all the right stuff at the best price. My experience anyway.

The compression test is pretty important on you vintage motor .There have been several cases of valve seats working loose .Not being an alarmist but establishing cylinder /valve seat integrity should be a first step .In fact probably should have been done before he started chucking parts .Second point -from a repair cost perspective big difference if engine in car or removed .Third point- parts prices will probably only establish a reasonable price by the repairer .Genrally they want the profit from the parts as well as labor .However it would be interesting if you volunteered Sunset prices . Good luck ....

I know that the dealer did mine with the engine in the car, the tech did lower it somewhat. He did tell me that Porsche says to remove the engine, but he had done this bank before with the engine in. I would assume that saves some $$.

I will talk to the mechanic tomorrow and try to find out what his approach would be. Would definitely talk to him about compression test first. I ve bought ton of stuff from Sunset. Will give them a call and find out cost of parts as well. I will keep you all posted on the progress. Thanks again for your help and support.

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imho compression test unnecessary. The fact the DME is logging misfire error codes (at least for cyl. 6) is telling that cylinder is suspect, most likely it is weak. At this point I'd consider a leak down test to try to determine why the cylinder is weak. I do not think it is a bad valve lifter. What I suspect is it is a burned valve. But it could be something more serious. Sincerely, Macster.

Macster -don't know how you can jump to your conclusion so quickly .I believe that all the computer is registering is that cylinder 6 isn't working correctly .Generally a compression test will indicate whether the cylinder can sustain combustion .The leakdown test is a good tool for isolating to rings or valves . I don't have the manuals for Variocam plus but in old variocam world the protocol is test the injector -coil-and then replace the lifters .

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The cylinder has already been flagged as not working correctly. While the engine is running the DME constantly measures the output of each cylinder by measuring the acceleration imparted to the flywheel by the cylinder's power stroke. If this acceleration is below (or above) a low (or high) threshold a misfire error code is logged and the CEL is turned on. In short, with the CEL on and error code P0306 logged, the DME has already signaled there's a weak (or overly strong) cylinder: #6. The issue now is why is the cylinder weak. (I am going on the assumption the cylinder is unlikely to be that much stronger than the other normal cylinders.) A compression test at this time is redundant. A leak down test can help identify the reason the cylinder is weak. Off the top of my head I would offer the opinion that at this juncture about all a leak down test will tell one is if the problem might be addressable with the engine left in the car or if the engine has to be removed. In short does the problem lie with #6 cylinder's valve hardware: Is a valve leaking? Or is # 6 flagged because due to a problem with its piston/rings/cylinder: Is the piston/rings/cylinder unable to develop/sustain healthy compression pressure? If the OP wants some other method of confirmation the suspected cylinder is weak and worth investigating further there is this: The tech with the proper diagnostics/test computer while the engine is idling can turn off each cylinder's spark and fuel. The effect in engine rpm/idle speed is noted. If a cylinder is weak it is contributing less than the other cylinders to the engine's total output and the idle speed/rpm will drop less when the bad cylinder is disabled. The VarioCam system can be tested as well. Off the top of my head I can't recall the test procedure -- it varies depending upon whether the engine is fitted with VarioCam (intake timing control only) or VarioCam Plus (intake valve timing and lift control) -- but it is spelled out in the engine's factory OBD manual. Sincerely, Macster.

You left one part out -if the valves aren't opening correctly it probably won't fire correctly .

Macster, dcdrechsel, A little more info. Leak test has been completed and the mech said at this point he is positive it is the sticky lifter. I will forward your points on to him though (just to get him to read what you all are thinking). He said compression test was not done but he said that would d redundant and would not give him any different conclusion. Work will be done with the engine in the car. Decided to do just one bank. He his willing to get it done even if I buy my own parts. Got a quote from Sunset and Pelican. Buying everything from Sunset except Intake valve lifters (which I am getting from Pelican parts for half of Sunset's price). Total cost - $758 for parts for one bank. I will post mechanic's email response to your thoughts once he gets back to me. Thanks again!

Sounds good and looks like it should be a sucessful fix !

Been here done all of this..... First go around was a bad exhaust lifter maybe 30,000 miles ago. So we replaced all of them on the right side. Then last Summer same issues as you are having. Did everything you have done and finally bit the bullet and said go into it(no need to drop the motor either time). Well this time it was not only a bad intake lifter on #6 but a broken cam!!!!!! Yes, right under one of the journals the darn thing was broke in half! Fell out in two pieces. So this time a new intake cam and all new lifters. Saved the motor most probably and lucky as I was pissed about the whole deal and drove the car for 10,000 miles with the problem. Car has 103,000 miles now and runs fine. From my research 99.9% of bad lifters are on the right side and codes always relate to #6?

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No need to post the mechanic's email response. If he says the cause of the engine's behavior/symptoms it is X he's at the car, he's at the engine. I couldn't disagree with him and have any firm ground to stand on. All that matters is if you believe him then do what he says will fix the problem. From the Porsche factory manuals I have access say to when a bad lifter is suspect all lifters of that type on that bank are replaced. I do not know the thinking behind this other than if one lifter is bad the others being of that same 'batch' are suspect too and replacing all is done to ensure another one of the original of a possibly bad batch of lifters doesn't go bad a short time after the bad one was replaced. My recollection is the cost in lifter hardware is not that much extra compared to the cost of labor in getting access to the bad lifter and replacing just that one. Be sure you save all the old lifters and if you want see if you can id the bad one. Sincerely, Macster.

Targan, Keep us informed on the progress. Thanks

I know it is possible to remove the cam cover and the cams to change lifters wit the engine in the car, but based on my experience I think it would take less time to drop the engine. Although many shops charge more I can drop the engine from my car (and it is a C4 so some extra steps) in my driveway, on jack stands laying on a roller creeper in about 3 hours.

Absolutely no reason to drop the motor. Plenty of room. If the book says to drop the motor they were smoking something that day.

Okay, this is getting more interesting. I put my car in the garrage while I waited for my parts to arrive from sunset. Two days ago, I pulled the car out of the garrage to wash and detail (good way to spend time with her when she is not running perfect :P ). Started the car, pulled it out of the garrage and had no CE light or mos-firing. I put the car on idle and waited and still had no CEL. Washed and waxed, then decided to go for a drive to see how long it takes before the CEL is back. 20-25 minutes of driving later, still no light and the car seemed to running perfect with no Mia-firing on all 6 cylinders. Parts came in yesterday and I drove the car to work again and it is still driving perfect. Dilemma now is, do I wait for a while and see if I have any issues? Or Like the mechanic said, may be the lifters get sticky only when the engine gets hot. P.S: Just a couple of weeks ago, I drive the car 250 miles and had no issues but the next morning CEL was on. It was 60 degrees outside. There really has been no consistent pattern. So, should I go ahead and get the lifters fixed anyway? Let me know what you all think.

Madison isn't very far from Milwaukee..... Does Nitrorocket work on Porsche's?

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IIRC you've already done the usual things to address a misfire: coils, plugs, injectors. The mechanic has diagnosed the source of the misfire as a sticky lifter. I've never encountered a sticky lifter in any engine though admittedly the number of engines I've been in contact with at that level is under 50 and that's probably high. But based on what I read on the various forums sticky lifters do not seem to be common. The only Porsche cars -- 2 -- I've encountered with any valve trouble is years ago, shortly after I bought my 02 Boxster I found a very very low miles used 02 Carrera and I asked about the car and the explanation was it developed a noisy lifter which was fixed under warranty but the owner had soured on the car due to this kind of repair so early after buying the car. More recently -- within the last year or so -- I came across a Boxster in for a broken valve spring. This car was owned by a woman who used the car as DD. The car had around 60K miles and I spotted the head off and looked at the head at its combustion chambers which were so free of any deposits I thought the head had been cleaned, but the tech told me that the head was as it came off the engine. The only other car (within the last couple of decades anyhow) that had a valve problem was a co-worker's Subie which generated a misfire error code. Eventually he had this looked into and the cause was a burned valve. So, what does this mean? Everything or nothing. We are back to your tech says it is X (sticky lifter). The fact the symptom is not present all the time doesn't necessarily render his diagnosis invalid. Have you talked to him about this intermittent characteristic and heard what he has to say? I note you mentioned you washed the car and then drove it some time afterwards. That's good. But it prompts me to ask: Do you sometimes wash the car and then do not drive it afterwards? I know my Turbo's engine gets wet after a wash because when I start the engine I often hear the belt squeal from the water. Anyhow, if you wash the car and then fail to start the engine and drive the car to thoroughly dry the engine (and the brakes too but that's another post), the misfire could be due to dampness arising from this treatment. Even though the coils are new they are not 100% immune from a large dose of moisture. Also, the problem may not be the coils but a related and marginal electrical connector/connection which allows a bit of moisture in which can interfere with a coil's operation. If the engine is cold or even warm, and then the car is washed, and not driven to dry the car/engine, the small amount of engine heat is not sufficient to dry the moisture but just make a nice humid micro-climate in the engine compartment. Next engine start and for some time after... misfires are possible. In fact if the problem were a connector/connection this can take some exposure to heat to dry the moisture. Also, the presence of moisture can result in a corrosion problem that could have the misfire problem present even though there is no moisture present. Sincerely, Macster.

I drove mine for 2 years like this with intermitent rough idle and lastly CEL. I lived with the CEL's for a few months and then finally bit the bullet. With the broken intake cam I am glad I moved on it, so it's hard to know if you have something like this that could cause even more damage? Tough call but after my experience I would say to get it in to the shop.

A few points.........The lifters are on a dead end street as it relates to the oil supply .One of the reasons they fail is debris .If the oil going in is contaminated the contaminent is still there .It might move enough under pressure to allow the lifter to fill -but it has no place to go unless it dissolves .I don't think there is any way to say for sure it won't do it again .The hard part of this one is that for peace of mind -it would be better if the car was throwing cel's and the lifters were replaced and no more cel's .Especially when the lifters were targeted by the process of eliminating other things . If it were me I would want the misfires up solid and the repair verifying that it was fixed .Which might happen if you drive it some more .

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The lifters receive filtered oil. They are no more on/in a dead end than any other critical oil interface. The lifter body has a chamber which receives the oil -- via a hole in the body fed by a groove around the bore in which the lifter resides and this groove intersects an oil supply hole fed by an oil galley in the head -- and this chamber acts to trap any particulate matter should there be any in this oil. (In the 993 engines Porsche had a bypass filter intended to filter out the finer particles that made it through the standard oil filter but dropped this bypass filter because it proved to not be necessary. The primary filter filters sufficiently.) The zero-lash portion of the lifter is in this chamber receives its oil not by a direct path but from simply being in the enclosed chamber into which oil under pressure is fed which in turn supplies the same oil pressure to the zero-lash adjuster. There can be an internal oil leak, a camshaft cover's 'seal' (a bead of sealant that of course gets flattened out when the cover is installed/tightened down) develops a leak that allows oil to leak away from where it should be into the area under the cover. This bead not only seals the oil inside the camshaft cover but keeps oil under pressure from being leaked out internally. If a leak has developed one (or more) lifter bores (in which the lifter bucket resides) may not be receiving a sufficient supply of oil. The result is a zero-lash adjuster may not pump up properly. Eventually due to lack of sufficient oil the lifter assembly degrades -- and even the cam lobe can be affected for the cam lobe/lifter bucket top are lubed by oil that seeps out around the bucket and its mating bore in the head assembly -- and then can begin to stick or just as likely has developed large (too large) clearances and the zero-lash adjuster no longer functions properly. (The fit of the zero-lash adjuster mating parts is so precise that even without any oil the fit so close that it acts as a seal and the zero lash adjuster is hard to squeeze/compress due to the air trapped in the small zero-lash chamber.) Sincerely, Macster.

Macster-nice write up .The point on dead end is that once oil/foriegn object is in the lifter it's there for the duration .This is not the case with the cam follower -if the hole on the cam follower is at 6:00 the oil will probaly seep out .Since this appears to be somewhat intermittent it is likely something is floating around .One would think that if it was a leak or insufficent supply the components would seize and not be intermittent .But you never know..........

Macster, dcdrechsel, and the others who chipped in - Thank you all so very much for your help. The good news is the problem is solved. It was a bad intake valve lifter indeed. I got it replaced and been running for about 2.5 weeks now and it is running perfect. No misfires, no CEL. I did see the faulty lifter after the mechanic got it out. It was just one lifter on cylinder 6 that was just getting stuck if you tried to move it. It was way extremely hard to push it down while the others would move like silk. That culprit caused me 6 months of pain!!! Hopefully, I won't have to deal with this again. Fingers crossed!

Good, glad you got it resolved and fixed. Did you change just the one lifter or the entire bank? Someone here indicated it's always/nearly always #6. Is that true?

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Yep, mine was cylinder 6 too. I wanted to change all the lifters from that bank but the mechanic tried but could not get to it without having to drop the engine and do it. So, I got 2 intake lifters and exhaust lifters on 6 replaced and am returning the rest back to Sunset. I am hoping the other ones will not be an issue. From what I have read too, #6 is always the problematic one. There is no logical reasoning as to why though.

Thanks for the feedback and glad it is a happy conclusion ...........

Not sure about the mechanic saying that he would have to drop the engine to replace the other lifters on the 4-6 side. To change any lifter on a side you have to take off the cam cover and remove the cams, and oncevthat is done you have easy access to all the lifters on that side. Seems strange that he said he could not do the others. Jake Raby has said that he often finds many of the lifters on an engine stuck. I know several of mine were stuck when I took the out. Good to hear that the car is running well, now enjoy it!

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Yeah plus 1 on that, once the cams are out test every lifter weather you think there is a problem or not!

Old thread but I found it while hunting for a Lifter problem.As the OP explains -it can be a $4000++ job! I posted some extra info here: https://rennlist.com/forums/boxster-...grade-fix.html It seems there are two issues: 1.the lifter part number(& design?) has been upgraded to address the sticking problem(?) 2.Generic or even re-branded OEM ,INA lifters are available more much less than quoted by the OP. That suggests a replace-them-all strategy because of the labor involved and the potential for expensive collateral damage. Let the Forum know what you do to help others in this situation?

Old thread but I found it while hunting for a Lifter problem.As the OP explains -it can be a $4000++ job! I posted some extra info here: https://rennlist.com/forums/boxster-...grade-fix.html It seems there are two issues: 1.the lifter part number(& design?) has been upgraded to address the sticking problem(?) 2.Generic or even re-branded OEM ,INA lifters are available more much less than quoted by the OP. That suggests a replace-them-all strategy because of the labor involved and the potential for expensive collateral damage. Let the Forum know what you do to help others in this situation?

Can someone confirm if the lifters on bank 1 (cylinder 3 specifically) can be replaced with the engine in the car? I've looked but can't seem to find a DIY for that.

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Why are you replacing the lifters for cylinder 3?

I've been getting intermittent misfires on that cylinder, only in low RPM. Revving the engine past 2.5k or so the misfires go away. Sometimes can go several hundred miles without a misfire being recorded, sometimes much less. This has been an on/off occurrence for the last 100 miles or so. A restart generally cures the misfire for a while. I tried coil and plug replacement, that didn't solve it. Given some research on this website, seems that intake lifters periodically being stuck in the open position can be a cause of the misfire. I've received a response in another thread that lifters can be replaced in the car, but also that it is very difficult with limited working room, so engine removal is recommended. While that probably makes sense for a shop, I am thinking that for me it may make more sense to try it with the engine in the car even if more difficult since I don't have a lift and removing and reinstalling the engine on the floor doesn't seem appealing, particularly if can be avoided. However, I can't seem to find any DYIs on camshaft or even valve cover removal with the engine in the car.

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The response you got back was from Jake Raby. If you don't know who he is just be assured he knows what he is talking about. He is a Porsche engine reconstruction specialist of renown. When he says something you should listen. Doing lifters in an M96 engine is NOT like doing them on a Chevy V8 or a Honda four cylinder engine...

You can do it with the engine in the car. Not a job for a novice though. Cam timing on the way back out is important too. You need some tools. You might as well do some other things like changing the pads and solenoid but that is budget dependent.

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If your talking about replacing the lifters I would questions whether it can be done in the car, have you managed that?, I don't think you can get the cam covers off and the cams out with the engine in the car. Honestly having done the job removing the engine isn't such a big job as it sounds. And with the engine out you can undertake all the other preventative PITA jobs with ease such as the AOS

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It is possible. My car�s lifters (and chain pads) were raplaced last year by local Indy, and engine was in the car.

One more thing to add. I have a C4S. Does the wide body help in this case with the extra room?

Had the same thing happen to our 996 4S. Chased around the coil, injector, etc. I told the mechanic to look at the lifter. Sure enough, it was a sticky lifter. Replaced while in the car. I still have that lifter as a paperweight.

RGS, did you end up replacing a single lifter or all 6 of them. Curious if this is a very rare failure and might as well leave the other 5 intake lifters in or if it is more common failure and might as well replace all 6. Also, do exhaust lifter fail? They are much less expensive than intake lifters, but they are simple bucket design and in my BMW experience those last a very long time and are not a failure item.

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We replaced the bank. While You�re in There. It was the intake lifter. The inner rod, for lack of a better term, was sticking. Almost scored and seemed to be tapered to create the sticking. I do not believe the exhaust lifter to be a common failure point for the reasons you mentioned.

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Agree that the exhaust lifters are pretty bullet proof and have remained unchanged, the inlet lifters have changed part # from what was fitted when built which means a design/supplier change

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I have removed the camshafts to replace the Cam Variator Hydraulic Tensioner with engine in the car. After the cams came off, the lifters just slipped out with a magnet. On bank 1, the cam holding tool fits easily, and the other bank you would have to slightly drop the engine to make room. The cam covers come off after you remove the exhaust headers and the mufflers, and of course the bumper has to come off. If you want to do a lot more work on the engine, then by all means take it out of the car. Clutch work, AOS, cooler, starter would all be easier with the engine out. But if all you need is access to the lifters, you can do it with engine in.