Slight leak of pink fluid (possibly coolant?) from front passenger side

Just got back from a road trip up to NY and back. Got home this morning, and after leaving the car for about five hours, I came back out to see a very tiny puddle under the front right of the car forward of wheel well. Pink and viscous, but aside from the radiator, I don't know what that would be. Nothing apparent after sticking my hand underneath and into the bottom panels. Didn't hit anything, no oddities on the trip... Brake assembly seems fine and no CELs, warning lights, etc... I just had the coolant tank and hoses replaced... And that went without a hitch... Sort of perplexed... Need to take off the rear panel, but soliciting ideas or anything to look for that could be overlooked easily. Thanks...

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Well, if i understand correctly the leak was in front of the front passenger wheel of car. Pink fluid is coolant. Ayk, 1 radiator is there along with its hose connections. Thats where I'd start looking. Take off the bumper and go from there...? Good time to clean out the radiator and ducts and between ac cond and radiator. Don't see why you need to take off any panel in the rear. jmo

Yeh, my bad on the confusion; I was referring to the "rear" panel that is the forward section of the wheel well. I put a cardboard piece under it to check it in a few hours. I wiped it clean about an hour ago and nothing has yet to reappear so hopefully it's a loose hose (fingers crossed). We will see how wet the cardboard gets over the next few hours. Thanks and appreciate it!

It may need pressure to cause the leak. pull the bumper, air boot and condensor. U wont see anything from the wheel well as the fan is in the way.

So I failed to mention that I drove directly from NY to work and it was in the parking lot that I saw the small puddle. Cleaned it and took a quick look/feel to make sure nothing was actively spraying/dumping fluid, then drove home (25-ish min) with nothing apparent after a look at home on the surface... Not sure if that is enough time for it to act back up. Just weird. I'll check again tomorrow and check the coolant tank before I head out, but sounds like this weekend will be a bumper cover and clean/inspect deal. Thanks again.

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When you had the reservoir replaced (wise move) and drained the coolant, did your garage, I'm guessing you had this done, use forced air when refilling with new coolant? I've read on rennlist that the service manual suggests a leak test with pressures to 20psi. Another user did mention that with all the old cooling hoses and connections that it is not really advisable to go that crazy and to take it easy on the old girl. 12-15 psi I think was quoted. This is just heresay I'm afraid I'm too lazy to go get the Bentley manual. NSFW ⚠️ Swiss Tony: "" You know Brian, changing the coolant in your 911 is a lot like making love to a beautiful woman. First, make sure you have plenty of fluids. Don't be cheap, it would be disrectful. Take her out, warm her up, gently, and then, when the time is right, she'll likely go and drain her fluids in preparation for the 'flush'. Then, give her a drink or two. When the timing is right, make your move. Stop pouring, and instead, pump the fluid into her, gently. You might think she's full, but don't be fooled. Take her out for a drive i and then back home, and full her up again. If you've done it right the first time, she may even need some coaxing. Don't be shocked if you hear "burp"..." ...and so on. You know how it goes. Or if you don't, search 'the fast show Swiss Tony' 🥸 and excuse my crude humor. It's the way I was raised. Blame my Brit friends for introducing me to the Fast show.

^^^Wow^^^ I sure didnt anticipate the Swiss Tony show�

Ha. I appreciate this humor and thanks for the feedback. I need to check what type of test/leak check was performed. I got up this morning and found a clean piece of cardboard... Drive to work is about 30 min (30-ish miles), so we will do the same when I get to work to see if it leaks again. Per Jeeper's comments, will be interesting to see if pressure/movement is required, but again, I drove it home from work yesterday and nothing appeared to be leaking or collecting... Either way, bumper cover off this weekend for a clean/inspect... Oil change next week...

While I can appreciate the humor, the best tool you can get is the Air Lift system for coolant fill up.

U can also loose coolant on the way hkme and it be dry when stopped and fluid can be sitting in the bottom of the bumper. Look for white snail trails of dried crust. Usually your nose is a good indicator of leaking rad fluid, its a sweet smell.

I was smelling a strong coolant smell after a drive; strongest near the passenger front. Not loosing much coolant when checking the reservoir. Was told by my indy that some radiator leaks are not going to leave any noticeable puddle since the coolant evaporates on the hot radiator. Bottom line, it was a slightly leaking front right radiator, had it replaced and now no smell or loss. Mechanic said leaf matter and dirt build up on the bottom tank and deteriorate the radiator, keep them cleaned.

Thanks for the responses and doing much of what is recommended already so winning...? Prior to driving and upon arriving at work today, had no drips, pooling, residue when I checked. Leaving today, still nothing. Got home, paper towel wipe and poking around. Got a bit deeper up into the bumper and wiped; there were two or three drops but not sure if it was just residue from yesterday. Nothing wet in any of the bottom portions, all dry, and no snail trails or any bleed off residue. Tank remains level, or if it is losing, it is not enough for me to tell or nothing fast enough to warrant immediate action. Indie and a few others think it might just be older components and the crazy temp fluctuations and weather might have aggravated a seal with some wear/give. Obviously know this could be a thing, but didn't think it could have that kind of an effect on the car, but if it is, news to me. Still getting the bumper off, clean out the cowlings and ducts, and give it a once over this weekend to include the water pump (although that was replaced at 62K). Thanks so much and will keep everyone posted for those that might be having similar issues.

Any chance it could fluid from the headlight washers?

The radiators on the 911, are almost identical contraction and material to the ones on a BMW, they last about 10 years to 14 years on the BMW then the plastic tank cracks. When I changed mine out , the plastic on the tanks was very brittle, teh tank seals agains a rubber o-ring against the aluminum core, not har dot imagine it wept then resealed but its a sign.. Your due for new radiators. IMHO they are a 15year service life item no less than a timing belt on some cars..

Going to take a look this weekend and we will see. Still no signs of further leaks. Will see what they look like and go from there. Thanks for highlighting and definitely budgeting for this. Don't think it's the headlight washer, but will definitely check underneath either way for integrity of those fluid connections.

If it were my car, and I have a lot of free time, I would remove the bumper cover, clean all of it out, and perform a pressure test to 15 psi at the coolant tank cap, and see if anything weeps at the front. Fix anything that leaks. If not, cover it back up and drive.

FWIW,, I put all CSF radiators on my car to replace the factory ones, they are thicker, all aluminum no plastic. I did the kit to add the 3rd center radiator as well, and am running the low temp thermostat. My temp gauge sits right on the 8-0 gap at 180 at pretty much all speed, when sitting doesn't seem to matter.. I did find that the couple of fittings the CSF have needed some thread sealer and better o-rings. I had a leak on one when I first installed. there are 2 hose bibs for teh blender circuit and two plugs that allow the left and right to be interchangeable. I used super silver hard silicone seal threads and a aluminum backed rubber o-ring on each.. 5 bucks..

Nevermind!

This is far from conclusive but I had the same exact issue and it was a leaking radiator. Basically continuous dripping from the front passenger side, more after a drive.

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This sounds like ninja ship. I am just trying to find a leak but really appreciate the follow through. Today doing a visual. Nothing leaking, not wiping. But tomorrow if I find fresh liquid or a puddle, problem. And pulling off the bumper regardless and cleaning out the yada yada yada.

Got the front bumper off and aside from the rat's next of crap I cleaned out, everything looked good if a bit old. Hoses were firm, not spongy or brittle. Seals all looked solid, again, if a bit old. Obviously the radiator units are old, and should be replaced (next major deal). Wiped out the inside of the bumper and checked all the hardware before putting it back together and nothing indicating a persistent leak. Underside panels all appeared dry, but I cleaned them down too. So... chalk this up to driving an older car through rain, sleet, snow, and experiencing a 40 degree shift in temps...? Will reply if otherwise, but knock on wood, the 996 powers are looking over this 4S... Thanks again for all the help!

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Good luck! Hope you find the issue!

So� looks like I misaligned the bumper cover. Everything went on pretty smoothly minus the reflector housing clips. Had to wrap up quickly and noticed these gaps. Car is 2004 and know there are minor design variations per each year. Any suggestions? Really hoping to not have to completely remove the cover but guessing something might be caught. Weird because it went in pretty smoothly.

Looks good� those gaps below the light were/are always there�

When you put the cover on ,, put all the screws in but loose, then push on the center and slightly upward till you like the gap under the light, and tighten the upper 5 screws, then as you tighten the rest of the screws, light pressure should let you get the gap correct everywhere else.. Hard to tell in the pick but it looks like your missing the lower rubber trim off the headlight module.. ?

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Huh, I am not sure about that to be honest... Anyone have a picture available or a part reference number? Great advice too and I did just that on my second break down which was way faster, more thorough, and resulted in a very nice and flush look (knowing that there is a little gap from the factory on these cars. Another thing that helped was breaking down the bumper going by the Bentley guide rather than a few DIYs or YouTube videos. Just worked for me. Now the bad news... It looks like there is a fine leak in the left side hose that leads down to the radiator. I got up in there again for a double check and noticed some sheen and moisture. Guessing the temps and weather aggravated what was likely to happen and... it happened. I tried to get a good picture of it but failed, however you can note the part number decal on the left has a pink tint, and when you put eyes on with a light, it's that hose that appears to have the slight leak. There was some residue on the upper side of the bumper cover that would correspond to where this hose is... So yeh... Again not bad and likely have to just replace the hose (I have to hold off on a full radiator replacement right now), but for getting back into the DIY scene with this car, this was a confidence booster. Going to change the oil this weekend; hit my 5K interval today, and figure out the PN for that hose... Thanks for all the help and patience and any reference photos or PNs for the headlight deal are welcome!

The hose in the foreground of your picture is an air conditioning line - is that the one you were mentioning had the pink residue?

Sh-7... and yes... and sh-7... And AC is not a DIY...

There is nothing in the A/C that is pink so it's very unlikely that line is leaking or a source of your pink stains. The airflow is pretty intense up there. Coolant can certainly migrate up that far.

Only 1 way your ac can leak pink/redish fluid. Thats if a tech used a red ac leak detector dye to find an ac leak. Fairly common with some shops. Even after the leak was maybe fixed, the pinkish color will stay in the oil till the compressor/ accumulator is changed and system is flushed. It will not harm anything... Does the ac blow real cold ? in hot summer weather..?

Yeh I just went through the shop manual and confirmed no pink liquid would be in the AC system (self-education). When I had the bumper off today to reset it, I ran the motor to see if anything decided to just start spraying, but it might have to be under load to effect a leak�? Whatever it is, it�s is minor but I want to get to the bottom of this� FWIW. The wet spot on the interior of the bumper was high up and in the �corner� where the rounding for the headlight would be . But guessing it either evaporated or maybe it was more residue? Either way none of the radiator components appeared damp/wet and with the rubber air intake above that mark, it didn�t have any pooling or residue� sort of at a loss right now. Time to table this for the night and any further suggestions are welcome.

We�re having whack weather right now, but going to run the AC tomorrow on the drive in to see if I get anything. Been 30-50 here so no real need for it, but in the interest of Rennlist, I will do it. Thank god for seat warmers 🤣

Likely the two problem hoses... or at least one of them.

The vent pipe is really close to that AC hose its got a coolant leak chance too. Also the crimp on the radiator looks damp, and thats a super common fail on aluminum radiators. If its a steam leak it will spray far from the source at time before it shows up...

Hmm. I have a scope� is there a way I can check these areas after immediately driving the car without breaking down the the bumper again using the scope? Pressure test is obviously the best way to do this but I don�t have the time or equipment to do that. Just trying to do this on my own and diagnose the problem before I have to resort to a shop. Welcome any ideas. Changing the oil this weekend so can jack up the car in the front after.

You can buy a UV dye kit for coolant at most places like Oreillys, advanced Etc.. You add it then run the car till hot and run the heater full blast, once hot,, best done in a dark garage, the UV light will show where the leaks are, whole kit is like 25 bucks die + LED/UV light. With the dye,, if you remove your headlight buckets you might be able to peek down with the scope, and you can look from below as well as through the inlets, but honestly taking the bumper off and running the engine is probably the shortest path. (I feel your pain I've had the same fun.) It will also at idle show if any coolant is in the exhaust pipes.. (Ie a crack in a cylinder or a badly damaged AOS. ) It also should show on your dipstick if any coolant is in the oil.

Thanks so much. Oil tomorrow and replacing the infamous oil pressure switch. That scared the **** out of me for a hot second. Have a low rev idle suggestion from my indie to test the coolant system. Will try that too. This is just exhausting. But at the end of the day, these cars are actually really easy to take apart and put back together.

Biting the bullet and likely taking it in due to lack of time between family and work to really get at it. That said after doing the oil change over the weekend, I got the infamous oil pressure switch failure. Intermittent functioning and then dumping at 0 or spiking at 5. Hit the conductors with Deoxide and a wire brush but have a switch on order. I feel that this will not be nearly as easy and straight forward as made out to be� 🤣

So follow up, again got a good under body wipe in with no signs of a leak or otherwise. I did check the engine bay and there is a little coolant discharged from the relief valve but nothing crazy, to my knowledge, normal when over-pressure occurs. I did top off the tank with roughly two tablespoons of distilled water, but still nothing indicating a catastrophic situation brewing. Now, the plan is to take a weekend in the next few weeks and replace both units. I am going with the "OEM+" options from CDF. Any recommendations or tips for this procedure, or the CDF units in particular are welcome. Have some research to do but rather have the phantom leak in the winter than a total failure in the summer. VA gets... nasty... Thanks again and really appreciate the patience and assistance trying to get to the bottom of this.

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The tank looks easy, till you actually try to pull it out, it's a Rubics cube to remove. Most seem to drop the motor via the rear mounts to maximize room. Don't over manage the coolant, if its clear up to the max line it will bleed some back out that tank holds almost 1 gallon on its own.. so, as long as its midway between low and MAX and the "add coolant light" is behaving your gold. Oh and change the darn coolant sensor while your there.. You'll see why.. If your drips were right front its not your coolant tank though, I would bet a ton that right front radiator has a tired crimp on it. They are 20 years old now, For comparison,, BMW says change the Berh radiators at 8 to 10 years.. or 100K miles IIRC which ever comes first. When I removed mine on the 996 they were sooo much worse than I would have thought looking at them in the car, the hose bibs/pipes the radiator hoses connect to are plastic, when they break its pretty much catastrophic.. as in all the coolant on the ground in about 1 second.. Here are a couple pics mine is a 2003/C4 with 118K on it.. The shiny one is a CSF the dirty one is the original Porsche and one of them still had the assembly line sticker on it. Tanks end From top side

Huge help and yeh, I am expecting a freak show. Definitely need to get the parts list right. Going for the CSF radiators, and all new hoses which are three per side based on the diagram of the radiator assemblies and all associated clasps, fasteners, etc. Any extra things you recommend having on hand tools, back-ups, spares? Huge help.

For the small vent hoses, I used Fuel injection hose clamps, they wrap all the way around the hose with a big overlap and they are smooth so they don't bite in to the hoses. The factory spring clamps on mine were kinda shot.. When you install the vent hose fittings in teh CSH radiators, make sure they have the correct size o-rings on them, one of mine had a slightly looser o-ring and leaked. Its accessible without totally pulling the radiators but annoying, I also used thread sealer on teh threads of them since there really isn't any reason to take them out, I did the same things on the two plugs CSF includes with the radiators. Because the CSF radiators are slightly thicker and have bulkier tanks, watch the replacement of the bottom screws that go in to the bracketry of the bottom of the radiator when you assemble them and install, if you have longer screws they could just barely hit the bottom outer radiator corner.. I ground the points off them on mine to give me a 1/4 inch of clearance.. Shorter screws are also an option, Porsche just used longer ones I would guess because they are easier to get started while assembling the car and they don't reach the original plastic radiator tanks. Also the hoses for the radiators use a variety of slightly different sized clamps, so its easiest to take it apart then make a run to Napa if you wish to replace all of them with the hoses. IIRC there are 3 sizes.. on the bigger hoses.. If your re-using the spring clamps, keep them sorted in order they don't interchange well. LOL My hoses were all in fine condition, I got some new ones with the 3rd radiator kit. I did the 3rd radiator option, its a fair amount of work, I'd guess it adds 3+ hours to the job, and assembling the mounting and ductwork is a puzzle.. I used a cut-off blade in a Dremel to cut the opening in the front bumper duct area.. Used a Drum sander bit in the Dremel to smooth the cut off . I only did the 3rd rad because I scored a deal on the whole kit. I cant get my engine temps above 180 now... Rock solid at the 8-0 point and I do have the cooler thermostat.. Well see how she does in July.. In the desert.