Idle problems any ideas

[rjo64]

Car has trouble running smooth for the first mile, stalls while driving and revs drop out when slowing down. When warm and slow down the revs drop down to 200 then pick up to normal. Has anyone had the same? Soooo many sensors where do you start?? Also do not know if it is related but my temperature gauge is reading 10 degrees cooler than before??

Edited by rjo64 on Tuesday 5th June 20:03

[R0162]

lambda sensor..common fault..Bosch universal work fine and takes about 10 minutes to change once you learn the access points..

[node]

was it left out in the rain at any point recently?

[rjo64]

Hi yes it has had to sit outside for a couple of weeks as garage full of new summer house at the moment. Have you an idea then??

node said:

was it left out in the rain at any point recently?

[node]

just let the engine bay dry out naturally or run the engine at idle for a 30mins or so. I think its to do with rain running inside and collecting around the fuse box which plays havoc with the electrics.

Try not to leave it out without a cover over it.

[rjo64]

Thanks for that. Do you know if it is a 4 wire sensor??

R0162 said:

lambda sensor..common fault..Bosch universal work fine and takes about 10 minutes to change once you learn the access points..

[2.5bluenob]

are you driving straight away or letting the engine warm up? I dont think the lamders start working till the engine is up to temp.

[Gadgeroonie]

might be worth adjusting the throttle stop up a little

[R0162]

Gadgeroonie said:

might be worth adjusting the throttle stop up a little

I was going to say that another possible cause is the throttle sensor moving out of position 1, but the cars starts ticking over better when warm...
It is not actually an adjuster on the throttle body, its a throttle stop, so adjusting only works temporarily as tickover is controlled by the ECU map, so whatever you change the position to the adaptive map will learn it and the tickover will return to its previous state..
So imo unless you think the throttle position could have changed please do not adjust it, because it inevitably leads to a downward spiral where you adjust it over and over to keep tickover up until it gets out of acceptable tolerance and then the ECU can no longer recognize position 1..
Then when you eventually fix the underlying problem you will not know it because the car will still not tickover properly due to the throttle position being out...

[dealmaster]

How about the coil packs? I has very similar issue with mine and turned out to be this.
Also sounds like a lambda sensor too though

[R0162]

I would have thought it would be more of a symptom for coil packs to play up under load rather than being a warming up issue?
but worth checking plugs and coils also...best to see whats going on with a diagnostics first..the software is free for download and the cable is available from SBD motorsport..

[dealmaster]

For me cold start was iffy. Revs seriously low and stalling highly likely. When engine warm and at idle (I.e stopped traffic or at lights) rpm sat at 400rpm. Jetstream changed coil packs and problem sorted.

[Plumber1]

R0162 said:

I would have thought it would be more of a symptom for coil packs to play up under load rather than being a warming up issue?
but worth checking plugs and coils also...best to see whats going on with a diagnostics first..the software is free for download and the cable is available from SBD motorsport..

Which cable is required and where do you plug it in, mine is running very rich

[R0162]

Plumber1 said:

Which cable is required and where do you plug it in, mine is running very rich

just phone them and tell them the ecu model, advise its a com port connection thats all the info they will need...i received mine next day..32.50+vat...
http://www.sbdev.co.uk/SBD%20Motorsport%20Display....


on mine the plug is in the engine bay, on the drivers side just in front of the power steering reservoir..

Edited by R0162 on Tuesday 5th June 22:09

[Plumber1]

R0162 said:

Plumber1 said:

Which cable is required and where do you plug it in, mine is running very rich

just phone them and tell them the ecu model, advise its a com port connection thats all the info they will need...i received mine next day..32.50+vat...
http://www.sbdev.co.uk/SBD%20Motorsport%20Display....


on mine the plug is in the engine bay, on the drivers side just in front of the power steering reservoir..

Edited by R0162 on Tuesday 5th June 22:09

So it's not the proper diagnostic port, but extra one flopping around on the loom

[worty]

Not sure what you mean by "proper" but I've never come across anyone using anything other than the one on the loom.
worty

Edited by worty on Tuesday 5th June 22:45

[Gadgeroonie]

later cars have an ODBII port - but it is not connected to anything !

[jaynobleM12]

Hey guys

I have an original m12, only 20k on the clock and have exactly the same problem!!! Its going back to the garage next week to get sorted, although they have gone over most things on it and struggling to find the problem.

Everytime i start it form cold it will idle for about 3 seconds and then die on me and cut out, it will always fire up straight away without fail, and will then find its idle position. I have to let it run for a few minutes, if i drive off before it will cut out when i next come to a stop. After a mile or 2 its perfect, just that initial start up and learning its idle?

any joy on on your mate?

j

[Gulf LS3]

sounds like an air leak somewhere to me, Lambdas work all the time but will only put the engine into closed loop when certain running conditions are met.

can you run a data log or diagnostics on the ecu as the problem will soon become apparent, each sensor should be able to be checked quite easily but if some of them are not working she would not run at all.

I know very little about the engine and ecu at moment but hopefully i soon will, an engine is an engine and symptoms on a LS V8 will be exactly the same as the Duratec, i would really look for a little air leak somewhere.

[jdearden]

I've had this similar problem after my rebuild a d it turned out to be dodgy ht leads. Replaced them with magnorcore ones n problem has gone