gkstar

The I/C pump on my C32 was replaced 2 months ago. I noticed a coolant loss at that time which I hoped was addressed with the pump replacement. Unfortunately, I noticed that starting about a week or so ago, I was quickly loosing coolant again - about 1/8 inch level loss per day. Level is now about 1" below where it should be, fault code will come up soon . I have read many post but hoped that a quick poll could help me and others.

Coolant Loss:
==========

1. Mileage - 40k
2. Coolant color at that time - yellow-beige or greenish color
3. Reason - specify one of the following: (still unknown in my case)
--a. I/C core leak - coolant goes into air intake path, color traces and clogging
--b. Transmission line leak in Radiator - coolant in transmission, tranny issues
--c. Leaking faulty I/C pump
--d. Other
4. Required Repair - tbd in my case
5. Other symptoms, besides coolant level change - like unusual transmission behavior...

Please post if you had to deal with coolant loss, seems it is not uncommon.

Eurocharged Rick

if you are not seeing it on the ground, then it is either leaking into your tranny from the radiator, or leaking out of your intercooler...

Bobby Dazzler

A C32 owner in the UK has had the same problem - I'm sure he'd be interested to know what the cause is. Last time I heard his dealer was all out of ideas.

amgmark

Check your radiator.. Make sure you have the upgraded/replacement one if you have an 02 and/or early 03.. Ask for a glycol test.. this will tell you if you are leaking into the tranny.. I hope you are still under warranty..

blackscooby

That would be me !
It's in at the dealers at the moment for a full investigation into the coolant loss. VERY similar problems. I loose approx 10mm water from the expansion tank per day, and put in approx 1l of coolant per week.

I had the coolant pump replaced in October and a couple of weeks later had the "coolant low" warning. It's been in twice since with coolant loss problems, pressure tested to no avail. No signs of external loss.

Now I've finally got MB to take the car in for investigation at their cost.

Hopefully I should know soon.

Cheers

Mark

blackscooby

Confirmed as Intercooler failure on my 02 C32.

gkstar

Thanks for sharing!

Do you know what they did to diagnose and narrow it down to this problem? I would suggest it to my dealer.

Will they be replacing the intercooler core with the same type or an improved design that will not corrode in the future? I read rumors that since recently, they use improved replacement I/C cores.

CynCarvin32

Low coolant: (7 months ago)

- clogged intake runners
- leaking intercooler
- repaired under warranty

You might want to press for new o2 sensors or cats since coolant in the combustion chamber can foul both very quickly. If you have had the issue for quite some time I would for sure ask for that to be done. One forum member here was able to have this done.

blackscooby

I've requested that the car is tested for emissions. MB UK seems very reluctant to replace such things as cats and sensors on spec.