crembz

Hi there... Just recently bought a c32 with about 130000ks on it after buying a w203k a few weeks back and being so impressed with how it drove. I've got my first problem less than a week in, hope someone can help me out here.

Anyways I keep feeling like the car isn't happy...did heaps of reading about ic pump failures and ic core leaks and glycol contamination. I decided to hook up my obd Bluetooth dongle and have a look at the data.

Seems cruising around normally I'm getting 80 celcius iat on 20 degree days! That just seems outrageous, my previous Subaru would barely get 3 degrees above ambient. The c200k is considerably lower.

So did some reading and some inspection and I'm leaning towards ic pump failure or possible airlock.

The reason I say possible airlock is that when I turn the car onto ign without starting the motor, i get all the usual fuel pump priming noises you would expect, but I also get a strange buzzing sound coming from the front right headlight area (drivers side in Australia). Placing my ear on the headlight it sounds like it is coming from right behind... Possibly below the headlight. It sounds like a dry pump activating for about 3-5 seconds (coffee machine makes a similar noise when it runs it of water). I'd have thought a dead ic pump would make no nose at all. The c200k makes no such noise, just sounds like everything is priming.

Based on this do you guys thinks it sounds like an air lock, how can I confirm it's an air lock and how can I remove this airlock? I'd buy a pump but I'd rather not dish out $130 and wait for weeks for it to get down here. Thanks for any help you can give me.

insame1

I'm not much help but my car makes the same noise. I just chalked it up the the IC pump priming the system.

crembz

I thought the same thing initially... But my c200k doesn't make that nose... And I doubt the c32 did when it was new. Now I'm seeing high iat so it's making me wonder whether it's not get coolant through our whether it's stuck. It certainly sounds like it's trying to work.

crembz

OK so I pulled the no5 fuse and relay out from the rear fuse box...buzzing noise remains so its not the ic pump that's buzzing. Had a feel of the coolant pipes running in and out of the ic. Cool to touch after the engine has been running for 10 minutes. Looks like there's no water running through the ic... New pump I guess.

Lenin

3 degrees C above ambient is what it should be. Regardless of the noise, it sounds like your pump is gone. Here is some info on how to purge the air from the system. https://mbworld.org/forums/c32-amg-c...ed-system.html

crembz

Thanks Lenin.

Had a read through that and tried it out this morning. Drive up and down the street (about 100m) and let it idle for about 20 minutes. Pulled off the overflow (yellow) line to have a look... Not a single drop coming out. At that point the radiator hose was hot, both ic hoses (red and blue) were still cool.

I ordered this: https://www.fcpeuro.com/Mercedes~Benz-parts/C32-AMG/?utf8=%E2%9C%93&keywords=BOSCH+0392022010&year=200 2&m=20&e=630 today express international... Hopefully get it this coming week. I read this is a straight swap... I've no interest in aftermarket or mods... Killed my last car with that.

I'm paranoid that it may be the ic itself leaking after all the problems with my other car. What should the ic pump sound like if it is working? How can I tell between the pump and ic without pulling off intake etc?

Lenin

Just monitor your IATs and if they are within 3*C-4*C, then the pump is working. Regarding a leaking IC, see if you are losing coolant after a month or so. If you are, you may have a leaking IC.

crembz

Did some logging today... After a 2 km drive on a 9 degree night and accelerating hard out of 2 corners, IAT was at 55 degrees. Then drove gently for 15 minutes on the freeway at 100km/h and the temp kept rising up to 84 degrees. It stayed there, fluctuating between 84 and 82. If I accelerated hard the temp would rise to 100 and not really go back down, supercharger didn't disengage at any point, however only reached 12psi Max boost.

crembz

Thought I'd update this, I hate threads that have no answer.

Anyway I received the ic pump within a week and installed it today. Was a real pain getting the mb house clamps off but other than that took about 45 minutes. Also noticed over the past week that the heat exchanger was always cold... Another sign there was no coolant flowing.

Anyway I lost a fair bit of coolant in the process... The entire reservoir so just filled it with distilled water for now. The previous owner had some green coolant in there so I want to flush it out anyway. Trying to find a local supplier for the zerex stuff.

Did some logging this morning... After a 15 minute drive and hard accelerating out of every corner the engine temp was sitting steady at 89 Celsius. IAT ... 32! And for the first time since I've owned the car I actually saw it drop ... From 32 to 28 once I calmed down! Wooo!

It was a cool day ... About 15 celcius... I'd have thought the IAT should be lower ... Like about 18 - 20... Maybe a radiator flush and new coolant will help with that since I lost most of the reservoir during the pump install and the coolant is a little diluted now.

Anyhow... Pleased with the result ...not to mention the $$$ saved by avoiding mb who wanted $950 for the pump and $500 for labour... Cost me $150 ans 45 minutes... Thieves!