coldhammer

I bought an o3 sl55. After buying it i found out that the cats had been removed and the resonator mod done.

Sometimes when under light acceleration 30% throttle the car suddenly lurches like it lost fuel and the engine just stopped. This happens for a half a second then the car continues on.

The symptom comes in spurts. Sometimes it will do it continously for a few minutes. Other times it does it once and then wont do it again for weeks.

MB has no clue what might be going on. Any one here have any thoughts?

G_KATS

change ur intercooler pump ...... its a common problem to older SLz easy to fix and doesnt cost that much to do .

i fixed mine a long time ago and put a Johnson pump.... dont go with Bosch. thats wat comes with the SLz from OEM. Ask ur dealer or garage to change it.

I did mine and notice alot more power that i wasnt getting b4. good luck and enjoy that beast .

coldhammer

I dont understand how a failing IC pump would cause the engine to stop?

jmf003

Wish I could help, Hammer. You're probably not getting a check engine light, which would give the MB dealer a fault code to diagnose.

I've never seen or read about the type of problem with a Mercedes but I have seen it happen twice in boats. Once was due to a failed condenser, which is obviously not a possibility with electronic ignition. The other time was due to water buildup in the gas tank. (Ethanol is prone to retain water.) The solution to the water-in-the-gas-tank problem was to drain the gas tank and replace the fuel filter. That'd be a complete shot in the dark and may or may not be related to the actual problem with your car.

Good luck!

coldhammer

didnt think about water build up. It definetely acts like a fuel filter issue. Perhaps I will just replace the filter and see what happens.

coldhammer

Just wanted to post a follow up for this in case anyone else runs into the issue.

Turns out my car had been chiped by kleeman.

I spoke to a guy in orlando that does a lot of kleeman mb and he said he had three cars come through in the last year doing the same thing as mine.

He said he tried everything he could and could never figure out what was causing the the issue. Finally one of the customers wanted to do upgrade to the latest kleeman software. Once the car was reflashed by kleeman the problem disappeared instantly. He then had the other two flashed and the problems disappeared on those as well.

So I had mine reflashed by kleeman and what do you know the problem disappeared instantly.

While the guys at kleeman insisted that the issue i was experiencing could not be related to the software tune they were using we have at least 4 cars that say otherwise. Something was definitely going on with the tuning.

Hopefully this will help others that might run into this odd-ball issue in the future.