When my engine is warmed up/hot the engine sounds like its misfiring when I apply just a little bit of throttle. For example I was in traffic (Scoops's fault) and when rising the revs slowly to pull off, reaching about 2,000 rpm and then sounds like its misfiring and wont go any higher unless I put quite a lot of throttle on and then its fine.

 

Any one have any idea what this could be?

 

Fuel starvation? Fuel pump? Maybe not a good spark.

 

Any help welcome :(

 

Stuart

check your O2 sensors ;)

Def worth checking the coolant temp sensor and harness wiring. I am surprised again and again at how much this little bugger is responsible for and the amount of problems it causes if faulty.

My latest little misfire was down to this, in fact it wasn't a little misfire-it was running like a complete sack of shite. Got a new sensor and harness and BINGO all lovely again...aahhhhh :D

Could it be the MAS? - that has a low revs safety limit when it screws up?

There a few things it could be. But I would start with -

 

TEMP SENSOR

INJECTOR WIRING.

MAS.

FUEL PUMP (& FUEL CONTROL UNIT)

PLUGS (& COILPACKS)

By the way........I have spare MAS and fuel pump if you wanted to borrow either.

Thanks guys.

 

I took both temp senors off a few days ago and gave them both a good clean. Its surprising how shiney they are when you scrub them up good. MAC would be proud of how shiney they where ;)

 

The plugs are only about 10,000 miles old but I will still check them and way, and I wil check out the wireing there too.

 

Could be the MAS, but with a MAS problem, it tends to be a more obvious misfire. This was really suttle, but I am not ruling out the MAS.

 

I was thinking more along the lines of a fuel blockage but Im not too sure now.

 

Stuart

Did you ever get this sorted Stu ?

Just wondering what it was in the end.