M3 devloped a misfire or hesitiation when cold

[scz4]

Hi guys,

My '98 M3 Evo (3.2) has started to develop a problem when starting from cold, could be the colder conditions now, never did it in the summer. It only lasts for 30-60, then the car runs like normal, still pulling hard as ever. I don't think it's running on only 5 cylinders, although it doesn't sound normal, very slow to rev and come down again, very hesitant. Car is standard except for a Dave F kit. No remaps etc. Inspection II was done just 5000 miles ago so plugs etc should be ok.

Any ideas what to look for?

G

[Schermerhorn]

scz4 said:

Hi guys,

My '98 M3 Evo (3.2) has started to develop a problem when starting from cold, could be the colder conditions now, never did it in the summer. It only lasts for 30-60, then the car runs like normal, still pulling hard as ever. I don't think it's running on only 5 cylinders, although it doesn't sound normal, very slow to rev and come down again, very hesitant. Car is standard except for a Dave F kit. No remaps etc. Inspection II was done just 5000 miles ago so plugs etc should be ok.

Any ideas what to look for?

G

Could be a fuel pump or fuel filter problem. Change the filter first, I think they cost around £10 and changing it won't be more than £20.

[scz4]

Schermerhorn said:

Could be a fuel pump or fuel filter problem. Change the filter first, I think they cost around £10 and changing it won't be more than £20.

Would that not have been done at the Inspection II?

[webweaver]

Might be worth checking no loose spark plug. Mine was missing a bit one day, next day it had blown a plug out, stripped the thread and melted the coil pack! Trying to find someone to helicoil it in situ.

[E30M3SE]

Could be signs of a coil pack beginning to fail.