only when cold!
only when cold!
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al 350i

Original Poster:

974 posts

225 months

Friday 11th May 2012
quotequote all
well after a nice break away i came back to tackle the wedge once more, managed to get her running, fault was with coil pick up on old distributor not working and the new distributor was causing problems because where the ignition module attached to the female connectors of the coil pick up on side of distributor, they were being pushed in and not giving a good connections.

the only problem now is that she will only run from cold! from start sounds good but after about a minute of running start's to run a little rich then gradually gets worse, will run for around 4/5 minutes before revs die and cuts out, will not restart until cooled down (30+ min). the length of time she does run is not long enough to show much coolant temp change and only enough to get manifold, block and surrounding parts warm/hot.

so was hoping if anyone can answer a few questions for me. coolant temp sensor in manifold is new and just as an extra precaution i've used a 1700ohm resistor to loop multi plug, are there any other sensors that could cause this problem? i noticed that there is a multi plug on the extra air valve and wondered if this could give a bad reading to ecu and if so is there a way to loop this too? my only other thought at the minute is if the engine heat is causing a problem with any of the wiring near the engine as it gets hot but not sure how i would check the quality of any wiring, is there any way to check?

vampire222

433 posts

179 months

Saturday 12th May 2012
quotequote all
Pull the cold start injector, see if it runs better without that, might be that it keeps using it even when it's on temperature. Also try getting a borrow ecu landy/sd1 flapper ecu to test if that helps.

Those would be my first two things to try.

al 350i

Original Poster:

974 posts

225 months

Saturday 12th May 2012
quotequote all
already got cold start injector discounected. AFM has been checked and given all clear. i have got 2 ecu's, one is original and one second hand but told was rebuilt but i don't know for sure so is possibly both faulty.

are there any 400se owners in kent that would be in a position to pop around and lend or hire a known working ecu for an hour? can pay beer tokens smile

vampire222

433 posts

179 months

Saturday 12th May 2012
quotequote all
The cold start air valve could be stuck open too, i know pretty obvious.

RCK974X

2,521 posts

179 months

Saturday 12th May 2012
quotequote all
From a general knowledge of EEC (rather then TVR specific) if it runs happily stone cold, but far too rich warm/hot, could it be the block temperature sensor has gone open circuit ??

(this will make the ECU think engine is always cold)

I know most electronic systems have them, I guess a 400 will too ?


ralph350i

791 posts

177 months

Saturday 12th May 2012
quotequote all
Hi Al
Sorry to hear your still having issues mate, but sounds like your getting closer, Check fuel pressure regulator is not leaking mate, just pull off the rubber pipe on the back off the unit, if fuel leaks then its shot, good luck

Cheers

Ralph