engine coolant low level

[elgrand]

Yesterday i had a low coolant level and there is no apparent leak.

I check my tank cap number and it finish by 01 and there is some moisture on the tank.

I also notice some moisture in the oil filling cap or something like that.

There is pictures of the coolant tank cap and oil filling cap.

I notice some pressure when i have removed the cap with cold engine.

My car have been store in a cold place last winter and the oil have been change 1 month before.

Does i have big trouble???

Thanks!

My car is a 996 2003

Manual 6 speed

American car now in canada

[phillipj]

First of all don't panic.

That frothy stuff on your oil filler tube is common. A couple things to check to give you some piece of mind...

Is the coolant in your resevoir clean? Does it look like it's contaminated? Check your dipstick..Is you oil clean? What you don't want to see is oil in your coolant and visa-versa. If your oil is clean and your coolant is clean you don't have a serious issue.

Is the water pump the original water pump on the car? Any leaks from the water pump?

You could have a failing AOS (no big deal repair wise) There are many threads here on that subject.

I personally wouldn't drive the car anymore until you have your problem diagnosed.

I'm sure some other people her will add to your questions.

Let us know what you find..

Edited May 18, 2009 by phillipj

[elgrand]

I check my dipstick oil and it is pretty clean.

My coolant is also clean.

What is "AOS" i think it's "air oil séparator" but not sure and how to check that?

Thanks for your help!!

[phillipj]

Excellent. But you still need to find out where your coolant went. Are you sure your resevoir isn't leaking? It is very common for the resevoir to crack.

Yes, AOS is the "Oil Air Seperator". A real common problem on M96 engines. If you do a search in the search box you will find lots of great information.

First of all start you car and try to take off the oil filler cap. If you have a lot of suction trying to prevent you from removing the cap this is a sign of a faulty AOS. Also take off your air intake and look at your throttle body. See if there is oil around the butterfly. If there is that is another sign of a faulty AOS.

Hope this helps and I'm very happy to hear there is no water in your crankcase!!! :jump:

Edited May 18, 2009 by phillipj

[elgrand]

ok i will check that

Thanks again.

I forgot to tell you that my water pump have been change and there is no leak.

[phillipj]

Good.. Also I think you need to update your coolant cap to the improved version that ends in "03". It think they are about $12 to $15 bucks online.

[elgrand]

Ok,i check for suction and yes,there is a lot of suction.

My throttle body have some oil and is not clean.

I have a real AOS fail on it.......

I will change my coolant cap and look on the forum to know how to fix

my AOS and clean my throtle body and maybe change the air filter.

[elgrand]

I forgot to thanks you very well Phillip.!!!!

Ciao!

Elgrand

[phillipj]

Your welcome! :D

The AOS part is pretty inexpensive. About $150. On a 996 it is a difficult install. This may be a job for your mechanic. You have a good mechanic to go to? (not a dealer.)

Here is a link to an AOS on a 996 thread. You have to drop the transmission to get to the part. As you will see most people recommend you have your mechanic do this job.

http://www.renntech.org/forums/index.php?s...replacement+diy

Good luck!!

:cheers:

Edited May 18, 2009 by phillipj