m42 318is help needed.

[E30GAV]

hi guys got an issue with my car.

use to be a 316i. . . .then dropped in the m42.

use to run well, had abit of an idle problem and use to cut out here and there, wasnt that bad.

just got the car back on road, on cold start up the car is fine, u can rev her and when the revs come back down it will idle again no problems.

but then when shes warmed up, evrytime the revs coms down so it can idle it coughs and just dies out. this is only happning when shes warmed up.

i didnt put this engine in my self, but looking at the exhaust i cant see the lambda sensor on there, and there is a small round plug in the engine bay which i assume it connects to.

could this be the problem??? im not enjoying driving the car at all.

[pac1982]

have a good look at all the pipe work could have a crack somewhere

[Saga]

My -is downpipes were not plumbed for an 02 sensor. This may be why you can't see an 02 sensor (not being cheeky!).

Are you using the DME to match the M42?

hi guys got an issue with my car.

use to be a 316i. . . .then dropped in the m42.

use to run well, had abit of an idle problem and use to cut out here and there, wasnt that bad.

just got the car back on road, on cold start up the car is fine, u can rev her and when the revs come back down it will idle again no problems.

but then when shes warmed up, evrytime the revs coms down so it can idle it coughs and just dies out. this is only happning when shes warmed up.

i didnt put this engine in my self, but looking at the exhaust i cant see the lambda sensor on there, and there is a small round plug in the engine bay which i assume it connects to.

could this be the problem??? im not enjoying driving the car at all.

[E30GAV]

what do you mean by DME?

the rubber intake boot that connects to the air flow seems to have small hair line cracks. but this was like this before, and it still use to run alrite.

[Saga]

what do you mean by DME?

the rubber intake boot that connects to the air flow seems to have small hair line cracks. but this was like this before, and it still use to run alrite.

DME = ECU. Silver box o' tricks containing PCBs, another 3-letter acronym.

Edit - Stating the obvious, but that boot may still have a split which isn't evident to the naked eye.

[asmith88]

does the plug which isnt connected, have one splitting off, also going to the afm and the tps?

if so it isnt required on NON-CAT cars

[E30GAV]

yes i got the ecu with the engine. . . .which was fitted.

il check with the plugs, but there is one that goes to the AFM which is currently conneted. the plug that im on about is near the battery, comes off the loom near there.

[DHFiS]

AFAIK the M42 for the UK market does not have a lambda sensor

[pac1982]

AFAIK the M42 for the UK market does not have a lambda sensor

Mine dont have a lambda or a cat and its a 1990

[asmith88]

AFAIK the M42 for the UK market does not have a lambda sensor

Mine dont have a lambda or a cat and its a 1990

snap

[E30GAV]

rite i take it mine doesnt hav one eitha, the engine was from a 1990 aswell. rite il try changin the rubber intake boot that goes on the afm.

[Dave_M3]

Could be the temp sensor playing up by still thinking the car is cold and therefore letting the car run excessively rich which causes the car to cough and die out when returning to idle after throttle has been opened

[E30GAV]

i heard about this temp sensor before . . . is it the blue one by any chance???

[Brianmoooore]

All M42 engines are designed to be used with or without a lambda sensor. If a sensor isn't used, there is a plug and socket in a white/black wire under the bulkhead wiring cover, near the middle, which must be pushed together.