COOLANT LEAK PROBLEM!!

Today after driving about 50 highway miles and stopping on a parking lot....smoke came from the engine compartment and coolant streamed out of my car!!! I opened the hood and coolant was coming out from under the cap of the coolant tank!! I have checked the coolant tank for leaks before but couldn't find any....can this be just a faulty cap?? My P is a 99 996 tip Cab, with now 66K miles...anybody had this problem before?? I know about the leaking tanks.....but this coolant was just steaming hot coming out from under the cap...

it was coming out from the cap ? thats strange was it tight?

I was as tight as I could get it....like when you shake a coke bottle and open the cap to fast...that the only real way to describe it....only the "coke" was boiling hot!!! and a lot came out....will bring it in Tuesday....wouldn't want to ruin the engine to save a couple of bucks!

have you or anybody have the cap off recently, thats reall only possible if the cap was loose or on crooked

I took it off a couple of weeks ago....to fill up a little bit of coolant....maybe to much...but if I remember well the P has been doing this since the beginning...but only sporadically....I checked the cap and it was tight and straight....but maybe you are right..I will check it out tomorrow.....the ****ty part is I put some coolant in that is not Porsche coolant (because I had to get home and didn't want to overheat my engine)...so I guess I have to flush the system anyways..

You don't know how weird it is to see 911 and coolant leak in the same thread. Good luck on the fix, wish I could help you.

I guess it is not really a leak.....it looked more like a spill....let's hope it is just the cap.

Check the p/n on the cap. If it doesn't end in 01, get the updated cap from the dealer (about $12).

Ditto on checking the cap part number. The part ending in 00 has had a tendancy to leak and the part ending in 01 is the later version which resolves the leaking issue.

Why Porsche doesn't use an aluminum tank and cap I'll never know. The plastic caps will warp and leak.

The cap is designed as a pressure release point is it not? So it may have been doing it's job if the coolant system was being pressurized - say by a head gasket leak. So after you've checked or replaced the cap - you may want to keep an eye on it in case there's something else causing cooling system pressure to spike. Chris.

I'm new to Porsche. Just bought a 2001 C2 cab with 9400 miles. I was following this thread and it occurred to me that I don't something. What is the normal running temp?

180 in the US model 996

p/n # is ending in 00.....so I guess that is the problem...will buy an new cap Tuesday! Chris....you are making me nervous...what else could it be?? head gasket leak?? don't you lose power etc....let me know...thanks

Go with the cap first - that's a known source for leaks, hence the recall and changed PN. Then keep a close eye on everything after you've fitted it: Keep a look out for temp, coolant level, and any leaking. You year of car is absolutely due for a coolant tank failure, and it's possible that this is starting, allowing the system to boil over due to it's inability to hold pressure. Leaks can be very small cracks, that only open under extreme pressure during driving. A pressurized coolant system can run at a higher temp withoit 'boiling', so any pressure release from the cap and/or a split tank could lead to coolant boiling over in a lower pressure system. The head gasket is much less likely, but would put pressure into the coolant system from the block, and would again show as potential coolant boiling over. You'd probably see coolant in the oil in this case, and possibly more white 'steam' from the exhaust during normal driving. I wouldn't worry about that for now - get the cap, keep a track, and report back. Chris.

thanks for th info Chris.....I will do the cap first and watch out for all the symptoms you described.

Yup, definitely start with the cap first. You've been around long enough to know that the old version has been the bane of many a Rennlister.

i bet u it's the cap, buy the new one. make sure u tight it up when the car is hot. i had the same problem before.

I had to replace the tank on my 1999 right at 66,000 miles. The crack/split is practically impossible to see....you may want to replace the tank as a preventative measure, to prevent you getting stranded or overheating your car to the point of damage. my .02 - Cam

I had the same problem on my '99 with 25k miles on it. I would look to replace the entire coolant tank. Unfortunately, it is a normal defect for that model year.

I have MY2000. How can I check the coolant tank and cap?

You can always get everything pressure tested. Does your car ever leak any fluid onto the ground? If not, do you have to add fluid to your reservoir every so often. If no to both of these then I would not worry to much about it. Mine just gradually got worse once it started leaking.

look uner the car a leaking cap will leave reisude on the heat shailding under it in trails to the ground and you will likely see it on the exhuast

I just noticed the other day in the reservoir, I was at the min. level. To be honest, I am not sure if it has been that way since purchase or lost some fluid. My car does run past 0 slightly when in traffic.

YES, I am with Cam here... Nicolaas, Replace your coolant tank if you have a chance because mine also leaked at 28k miles under hot coolant pressure from a small crack deep in the back of the tank so impossible to see it. The cap will help for now but later-on you may get a crack from the tank eventually, assuming this is your OEM tank... At that time, you will have to replace coolant and bleed again. Good luck!

I accidentally cross-threaded my coolant cap once and it leaked a little. Luckily after I straightened it, no more leaking. So be careful of that too.