My 2003 C32 has 87k on it. Replaced the intercooler pump at 40k. Last week (one week after transmission flush, replacement of supercharger bearing, and radiator change) the typical problems of IC pump failure-no acceleration, "visit workshop, ESP " warning, just like it did the last time the IC pump failed. With the help of this forum, I replaced the IC pump in an hour. Bled the line by pinching the water line coming down from the SC and all. Didn't work. Swapped the fuse in the trunk even though it looked fine. Still no go. Ordered a new IC pump and installed it last night. Checked it first by hooking the harness up to it ever so briefly before I installed it and it worked while the car was still running. Refilled coolant, bled the system. Still no go. So I bought a new switch in position 3 or C in the trunk fuse box. Still no go. Before I cry uncle and take it to the dealership, does anyone have any last minute suggestions? I'm fried...

That does not sound like ic pump to me. Usually when ic pump goes out there won't be any warning lights, just lame performance.

I think it's either the tps, throttle body or the wiring harness that connects to throttle body. I would try cleaning the harness and ziptie it.

Buy a code reader, or better yet, have a professional Indy Mechanic pull the codes. Many code readers will read basic codes, but some are "hidden" and my mechanic's reader can only see them.

That will point you to the problem. I failed IC pump will not throw any codes.

++1 on the Throttle body.

Where are you located??

+1 tps, throttle body
You'd better spend those money on STAR than rushing to buy a new IC pump.
There would be no codes, plus the car doesn't feel sluggish when it's cold. A couple of hard accelerations and when it shows the symptoms.

Interesting thoughts. It threw this warning the last time the IC pump went bad and they symptoms are exactly the same. First rev in the morning seems better (although the engine does rev a lot higher than normal) and then the car goes flat. i am assuming that is the SC shutting off with the high intake air temperatures. I can't hear the IC pump going after the car is shut off, although that is after the limp mode starts-maybe it is shutting it off. I can't feel any water flow through the line from the SC when I pinch it off (thinking that this was a air bubble issue).
I was under the impression that buying an aftermarket code reader wasn't really worth it due to the fact that they were so imprecise with our MBs. I read in one post where a guy put a multimeter in the trunk where the relay is and was able to show draw from the pump at 3 amps, but I couldn't tell where he had his spade bits shoved in to the relay holes. Lizardjack, what is a "tps"? And if it is the throttle body, how much of a job is it to replace?

Just looked up throttle body. $600...Ouch.
Gramma_Benz-I am in Sacramento.

My best advice - get it scanned with STAR diag!

TPS is Throttle Position Sensor. There is a way to check if your wiring harness is the cause of this (courtesy of C32Kompressor (I believe))
1. Put your key on position 2, don't start the engine
2. Open your hood and listen towards the back of the SC
3. There should be a whining electrical sound coming out of the throttle body if your wiring harness is okay.

In all seriousness though, +1 on Lizardjack's advice instead of throwing parts at it.

Throttle positional sensor. Its on the gas pedal assembly. Replace it.

The throttle body does not go fubar that easily.

I had limp mode about week ago all of a sudden, pulled over and restarted a couple of kms limp again and ESP error. Restarted and drove home next day bought some zip ties and electrical cleaner: has not happened since (have been using it daily this week). Touch wood.

FrankW could you pls advise if this the correct pn# 211 300 08 04? (TPS)

Look, u can replace half of the car's components just following every advice.
Just get it scanned!!!

Made the appt at the dealer to get scanned for Saturday. Will update.

Ddtham-which harness are you talking about? I am not sure which one you suggest to ziptie.

He is talking about the connector on the throttle body. Over time, the connector gets loose Which causes loose contact and cause limp mode.

If that connector is fine the other thing that easily causes the car to go into limp mode is the actual throttle position sensor. I do not remember the part number, but it is one and the same with the gas pedal assembly.

+1

I would take off the connector and spray it with electric cleaner and let it dry for a minute or two before reconnecting it with a ziptie.

The black connector sits right on top of the throttle body that connects to the supercharger to the back of the engine. I wished I have pictures but it really is straight forward.

I would bet that is your issue. TB does not usually go bad that easily.

I'd avoid the dealer, they're just gonna rape you.

Just find a qualified, highly rated, independent MB Mechanic.

So I took it in to the dealer in Rocklin. The clutch on the supercharger gap is too wide, and the SC cannot engage. Wow...I did the repair on the SC pulley bearing three weeks ago and was fine for a week or two. I checked the gap myself when I did the install and it was perfect...Will take it apart this weekend and gently tap the bearing in a bit more. Hope this is not a reccurring issue.

I've never heard of that issue before, did they tell you what too much gap is?

He replaced the bearing, every thing is possible.
Anyway, what is the gap?

.20 to .40 but the best way is to get the pulley as close as you can without it touching anywere. this may require install and removal a few times to get it correct using various thickness shims

The bearing should be the same size as the old which should be put back together in the same spot. I just dont see how it can cause gaps if everything is put back correctly?! Unless it wasnt installed properly. However the s/c not engaging will just make the car slow, not triggering esp and having high rpm spike on idle.

Well, suspicious coincidence. He tampered with the pulley and then the power loss accrue.
Anyway, worth to check it.

I did not get the exact code from the dealership, but he said it pointed to the SC clutch. Indeed, when I got it home, the gap had widened since I installed it. When I did the initial bearing change, I took it in to a local machine shop to pop out the old bearing and press out the new. When I got it home and installed it, the gap looked wider (it is indeed supposed to be .2 to .4mm). I called the machine shop guy back and asked him if he could press the bearing in a bit more, but he said he could not, that it was pressed in all the way. I got desperate and took it out and tapped the back of the bearing forward a few times with a hammer and then it fit perfectly with a .3mm gap. SHould have known that a few taps "in" would mean easy "out". I am sure that when the supercharger engages, it does so with a fair amount of force and it is pushing the pulley wheel forward/off the bearing a little each time. I just got done with a plug/wire change and tapped the bearing in a little again, but after 15 minutes on the freeway, it is back to honda civic mode. I think I am going to post a "want to buy" for an original pulley for the SC. Surely there must be someone out there who put a high performance pulley on who wants to sell their original. I am suspicious the guy at the machine shop may have buggered up the pulley itself in that the bearing is not very tight in there.

So you say the gap is wide again?
I replaced the bearing myself, as far as I remember there is latch-ring that would not seat in place unless the bearing is fully seated. Plus it'll never move once it's in the grove.
May be bad contact in the clutch connector?