2002 E240 "lumpy" idle and check engine light

[Profuminif]

been having an intermittent lumpy idle for a few week, today in traffic it returned, along with shortly after the CEL, will look to book it into the local indy to see what they think, but just wondering if there are any simple things to check for easily before i get it there

many thanks

Simon

 

[lynall]

Do a search on here for 240 as i think this came up recently was on a c class but same engine.



Lynall

 

[BlackC55]

The problem is normally caused by either ignition leads or coil packs.

 

[Profuminif]

thanks guys,

will call the indy and get them to check the fault codes tonight or tomorrow and take it from there.

Simon

 

[Profuminif]

well it went on STAR, and the verdict was a missfire on cylinder 1, so guess its plu, lead or coil related most likely, booked in thursday for a proper investigation

Simon

 

[lynall]

I think number one cylinder is drivers side front, at least its an easy one to get to.

Not sure what the cost isfrom your garage but new coils are on e bay.

Here £65 http://cgi.ebay.co.uk/Mercedes-CLK-...s_SM?hash=item3a47390df9&_trksid=p3286.c0.m14 this is the bottom view so it looks wrong but is the correct part, several second hands ones on there as well.



Lynall

 

[alexander patie]

usually the plug leads, but just testing them with a meter is not good enough, they can still read ok. ideally you would swap them with another cylinder and see if the fault moves, but beware, the terminals on the leads are fragile and easily broken

 

[Profuminif]

well change of plugs and two new leads fixed the problem.

the garage reckons they were the original plugs as they had the Merc star on them, not bad i guess 60k miles/7 years

Simon

 

[BlackC55]

Did you change them all?

 

[Profuminif]

yes, all the plugs were changed, but only HT leads on cylinder 1

simon