Need some help please

[clio_rsi_turbo]

Ive just gotten my car ready for sale, and ive just found someone willing to buy it, but the day before they arranged to collect it, it started miss firing! sods law.

its almost like it running on three clyinders but it wont do it all the time, sometimes its hard to start too.
so far ive replaced: exhuast sensor, dizzy cap, rotor arm, ht leads, spark plugs, map sensor, removed injectors and checked they're working fine and evenly, checked fuel pump, renewed coil pack & cleaned the ICV, all with no effect!! ive also removed every single electrical connection and coated with WD-40.

So as you can imagine, im pretty pissed about it having spent all this money with no effect at all!

Anyone have any other suggestions? help me please

[clio_rsi_turbo]

Ps its just a standard valver lump in there.

[arj256]

Theres no oil on the spark plugs / Ht leads?
Could have a leaking rocker cover gasket.

Give your earths a check.

[clio_rsi_turbo]

there was a little oil on two of the spark plugs, by that i mean on the outside, could that really cause this tho?

[arj256]

Depends how little it is.
If its enough to get between the contacts of the lead and spark plug then can cause problems.
Made my old valver misfire that did.

[clio_rsi_turbo]

ok well i'll double check it tommrow, cheers mate.

[drsmith1979]

also check the coolant temp sensor, can give a dodgey idle and poor running. When changing the leads, did you put them on the right order into the dizzy?

[drsmith1979]

also check that the ecu compartment isnt damp or wet so causing issues there.... oil in the plug wells will more than likely be from a leaking rocker cover gasket...

[BRUN]

TDC sensor can cause various problems, especially poor starting, has that ever been replaced ?

[Coops]

comp test it aswell to eliminate h/g failure.