Calling out all e30 Guru's

[fannyj]

So my car stutters at 2500rpm, had it tested on some machines and it appears that the car is running lean at 2500rpm. The machine indicated that there is more air that fuel in the mixture. Above that rpm it levels out and is perfect again. So under initial load the car is having difficulty.
I have replaced plug, leads, rotor, dizzy cap, main relay,fuel pump and filter.

So here's the question : Could the injectors cause this ?

[less2303]

Air Flow Meter?

[fannyj]

replaced the AFM already

[Handy]

Have you checked all of the gaskets on the inlet side?

[Geeman]

Could be a cheeky air leak. You checked the intake bellows and other air pipes...?

[Demlotcrew]

Try a mates ECU.

Andrew

[HartgeH27]

What area are you in ????

[toby]

Like Giles said... it could be a cheeky air leak. On the machines you tested the car on were the unburnt Hydrocarbons visible on the display? If this figure is high it could indicate an air leak. (Appologies if you've thought about this already.)

[Globulator]

Could the injectors cause this ?

The misfire could be
one cylinder cutting out, rather than all cylinders going lean. It could also
be cutting out above 2500 too but you just cannot hear it - do you have
a graph of mixture vs revs from the exhaust gas analyser?

I'll assume all HT electrics are new from your description.

I'd be tempted to do a compression test and get the injectors cleaned
and tested - it might cure it and it might help performance anyway.

Otherwise I'd try a different ECU or chip.

[fannyj]

the hydrocarbons are perfect, the technician double checked them. I have tried my brothers ECU, it makes no differene. I have inspected all hoses and the boot from the afm to the throttle, had most of the gaskets replaced about 2 months back and still makes no difference. I think i will have to have a compression test done and the injectors cleaned out.

If there's an airleak, would it affect the entire rev range ? and idle ?

[stevetigger]

What area are you in ????

South Africa