Poor warm idle stalling

[SteveH]

I have a problem with my car at warm idle with it dropping revs really low and stalling. It's fine from cold and it only happens when the engine has started to warm up. I've also got a problem with the water temp feed to the clocks from the MFTS, so I'm wondering if the water temp signal has a direct interaction with the idle control? I think I have a dodgy sensor or the cabling needs attention.

Anyone have any ideas what to look for or test?

Cheers,
Steve

[rynaqui]

Bad MAF could also cause dodgy idling.

[AndyP]

The MFTS does not feed the ECU, the sensor on the back of the head does that. I take it you've tried cleaning the ISV?

[SteveH]

The MFTS does not feed the ECU, the sensor on the back of the head does that. I take it you've tried cleaning the ISV?

Thanks Andy.....so the lack of temp readout on the guage is just down to the MFTS or it's cabling. The ISV has been cleaned and it works fine when the car is started from cold. It's like the ISV isn't getting the right signal when the coolant is hot. The revs dip really low and the car stalls when stopping at junctions. If it's left running it idles fine. It must be something to do with the throttle closing and the ISV circuit not kicking in correctly. I can hear the TPS click when the throttle closes and I have tested the TPS signals and they are all fine.

[UrS4boy]

Click on the MAF, MFTS, ISV and Idle Switch labels in this diagram to help figure out your idling issue:

http://members.shaw.ca/speedtek/UrS%20Engine%20Bay%20Device%20Map.html

[prj]

Vacuum leak. This is exactly how it will behave if you have one.

Pressure test it, then everything else

[SteveH]

Cheers guys

[andy10v]

3B ecu uses the MFTS. Are you 3B or converted to ABY?

[SteveH]

3B ecu uses the MFTS. Are you 3B or converted to ABY?

Still 3B at the moment, however the paln was to convert next week. I think I'll do the pin swap and see how she runs afterwards.

Thanks