c180 missfire thru out the rev range

[dervdoc]

i bought a 2000 c180 classic last night,starts and idles fine but when you put load on the engine, ie;heavy throttle it miss fires thru out the rev range, or if i just lightly press throttle with less load on the engine it revs out as normal,first thing to my mind is coilpack? is it a common occurence? dont know if it does this on idle as car was warm when i got to it.any help appreciated

 

[markjay]

Any error lights on the dash? You'll need to get the engine codes read, rather than a stab in the dark. Plugs, coil packs (which one? there are 4), low compression on one or more cylinders (head gasket? burnt valve?), timing, fuel issues, sensors.... and these are just a few possibilities.

 

[dervdoc]

no light comes on at all,

drove the car when cold,its even worse than driving warm, will hardly even rev out over 2k and idles really poorly, definately sounds off a cylinder, but when warm it revs out as i said in previous post

 

[horgantrevor]

it sounds like spark plugs check them and clean them or replace

also it may be ht leads or coil pack

but if it was me start at plugs and work back the cheaper option

i had the same today on a s class and it was plugs some one fitted irudium plugs which are not right for the car stock plugs you can go wrong i had a old set i cleaned and the car left my place humming and a happy owner

 

[dervdoc]

right, still not fixed, update is as follows, spark plugs changed, coilpacks changed,no difference, so plug in for fault codes and missfire on all cyclinders is showing, would this be due to a dodgy camshaft senor?
help please

 

[dervdoc]

also compression test was carried out and all is fine in that area

 

[dervdoc]

or could fuel starvation be a cause? fuel pump in bad nick?

 

[krisml320]

i had the same problem with my ml320. ive change alsorts plugs, ht leads . airflow meter, and its just gone pear shaped and its all down to a crank sensor being faulty.