1998 C180 throttle problem.

[jibcl500]

All

I have as above a C180, I had a misfire so Ive replaced one coil pack with a new one and the misfire has gone, the other problem thats developed in the last week or so is this, whilst driving, from a stationary position when I pull away gentle use of the throttle pedal is fine but it I plant the throttle the engine chuggs and the revs go down rather than increase and as I release the throttle the revs pick up again.

Its not my car a such, I just look after it, the owner has put half a bottle of redex in the tank but I dont think this would have an impact on the throttle.

Any ides anyone please.

jib

 

[television]

This almost sounds fuel related, what is the car like at say 50mph, any hesitation

 

[jibcl500]

Malcolm

On tickover the car is lovely and smooth, select D or R and the car moves under its own steam so to speak, press the throttle gently and it will increase the revs as expected, push the throttle down to increase the acceleration and the cars revs drop. At speed it will do the same.

I Park I can bring the revs up to 3500rpm gently and it feels fine blip the throttle at that RPM and it feels like its choking.

jib

 

[television]

Malcolm

On tickover the car is lovely and smooth, select D or R and the car moves under its own steam so to speak, press the throttle gently and it will increase the revs as expected, push the throttle down to increase the acceleration and the cars revs drop. At speed it will do the same.

I Park I can bring the revs up to 3500rpm gently and it feels fine blip the throttle at that RPM and it feels like its choking.

jib

Not all 180s have a MAF do you have the first 6 vin numbers 202018 or 078


Welcome to the forum Jib, there is a lot og good people here

 

[jibcl500]

WDB2020182

jib

 

[jibcl500]

Malcolm

Yes it has the MAF fitted, Ive found on eon ebay £50, would it be the same MAF on the C190 as the wifes 230 SLK?

jib

 

[jibcl500]

think ive just answered my own question, the MAF is the same but will check the SLK tonight when the wife gets back, just need to distract her whilst I take her car apart!!!!

jib

 

[BlackC55]

Sounds like a missfire under load. It could still be related to your ignition problem.

Also I have had another thought. The throttle potentiometer inside the throttle flap housing may be faulty. It may not be able to read the throttle position.

Get a fuel pressure tester and watch it when it faulters. If the fuel pressure drops when it faulters then BINGO.

Hope this helps