E30 M3 Converaion

[pmautomotive@ho]

Hi all

I'm after a bit of advice, I run a workshop and had an E30 with 3.0 M3 Conversion dropped im. Was supposed to be running rough but when it came to me. It wouldn't fire at all.

Basically I've narrowed to down to massive over fueling on crank. It's flooding the cylinders. If I disconnect the injectors after its turned a few times she starts to fire on the fuel lying in manifold.

No fault codes in diagnostics other than Lambhda sensor. TPS has been replaced, Injectors check and cleaned. New fuel, bypassed fuel regulator and ran a manual one to control pressure.

Would appear ecu is demanding full throttle fuel ok crank.

This conversion isn't pretty on the eyes.lol But would be nice to at least her running for the fella going forward.

It's had an Airflow delete as well by means of replacement ecu chip.

Any help appreciated
Thanks

[harveyottotech]

I would check scan tool data and actual voltage of the coolant temp sensor. If it's telling the computer that it's much colder than it is, it will dump lots of fuel to get it going. It may not have a code but could still be sending wrong data. The lambda info won't be used until it's warm, so I wouldn't expect that to have an issue. I would also ask if there is a tune and if maybe they turned the fuel injectors up across the board in a wrong headed attempt to make the engine run safer and fatter. That would be weird. I would expect to see maybe 5ms of on time at idle, or something near that. See it the tool will show that to you. Maybe it will give you an idea.

Hope this helps

Andrew

Sent from my KB2007 using Tapatalk

[pmautomotive@ho]

Thank you

That was my suspicions also. But I'm using Launch with the old BMW adapter lead and the live data stream isn't very useful.

Can you recommend a scan tool that's good for old BMW's?

[pmautomotive@ho]

Wee bit of an update on this. It actually started randomly one day and ran back and forward through the day and then reverted back to non start. It seems the overfuelling isn't the main issue. When I attach a spark to a coil if seems it sparks for a few seconds and then stops.

I've scoped the crank sensor and its producing a decent signal with an evident TDC. It's reading 0.520omhs of resistance which would appear to be within specs.

What all signals does the brain looks to produce a spark?

I've have fuel pump coming on and injection occuring.

Thanks