firing on 3 cylinders

[gordon100]

hi
can any one help my 1997 c180 when it heats up it starts to fire on 3 cylinders i have put new plugs in and i have put new coil packs in but it is still firing on 3 can anyone help please.

 

[brandwooddixon]

Have you tried disconnecting the MAF?
Sometimes when this fails it can give misfiring symptoms but doesn't tend to light the Engine Warning Lamp.

 

[gordon100]

hi
tried that car just the same

 

[jibcl500]

Compression test is the next thing to do.

jib

 

[Steve@Avantgarde]

I would say check the wiring that goes around the back of the rocker cover that feeds the ignition coils would be the next thing to do. Often the loom goes brittle, rubs through and arcs or breaks and cuts the power to the coil.

 

[Some guy on the internet]

OP, what are the first 6 numbers of your engine number? It'll be on your V5C.