1996 C280 sport - BAG OF SPANNERS!

[PLOD412]

I have a 1996 C280 Sport with 113k on the clock. It has a full stamped up service history and was serviced locally (Not by Merc dealer) just before I bought it in Nov 03. Having just sorted out my erratic idle by cleaning out the throttle housing (Thanks M J Tray!) I am dissapointed to find that when accelerating away from a hazard (normally a roundabout or uphill) whilst changing up the lower gears (Automatic) I get a series of popping like small backfire noises. After a few seconds and more acceleration this disappears until the next time. I am in dispute with my good lady as to where these noises are coming from! She seems to think they are from the rear exhaust area and I think they originate under the bonnet! Has anyone got any ideas/advice before I have to take it for a diagnostic check and end up throwing loads of money at it?
Thanks! : :cry:

 

[piestore]

lop

Hi
sounds very like air mass meter problems, borrow one from similar car if at all possible, coz thats all the dealer will do because the air mass meter very often doesn't give a afult code

 

[guydewdney]

sounds like one of the pipes isnt sealed right - popping is often due to extra air getting in. check the jubilee clips havent been over tightened and have cut the tube.

an old trick is to spray wd40 on the outside of the pipes - if the revs change then thats where the leak is.

 

[Robert Cox]

This same popping on acceleration has been discussed recently on the U.S. MB C-Class Forum (also happening on a C280)

See http://www.mercedesforum.com/forum_topics.asp?FID=8, item "Noise when Accelerating C280 1995" on page 3 where Benzgirl says...

"My 95 C280 does that too, I just bought it and I thought it was backfiring, I tool it to my Benz mechanics(I've owned a 190E and a 300E ) and they added that it supposedly needs a wiring harness"

Hope this isn't the case with your car as it appears to be a big $$$ job.

Cheers,

Robert