running very rich.

running very rich.

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gruffalo

Original Poster:

7,529 posts

227 months

Friday 18th April 2014
quotequote all
car is misfiring when I put my foot down and is running really rich.

One Lamda is unresponsive but as Lambda control is turned off on the ECU could this be the problem, every thing else is reading perfect?

Injectors, coils packs, leads every thing else is new so should be OK.

gruffalo

Original Poster:

7,529 posts

227 months

Sunday 20th April 2014
quotequote all
N7GTX said:
gruffalo said:
car is misfiring when I put my foot down and is running really rich.

One Lamda is unresponsive but as Lambda control is turned off on the ECU could this be the problem, every thing else is reading perfect?

Injectors, coils packs, leads every thing else is new so should be OK.
Coolant temp sensor? Will cause rich mixture if stuck at cold.

A misfire results in unburnt gases which the lambda detects and more oxygen from the misfire will cause the ECU to increase fuelling.

By revving and lifting off can you get any movement on the unresponsive lambda?
Engine coolant sensor spot on as is every thing else except Lambda 2 that does wake up for a while when I blip the throttle then it returns to zero, could be an ingnition lead issue I suppose making the lambda 2 read zero as it trying to weaken the mixture off due a misfire but the Lambda control is turned off so could the whole issue be caused by a plug lead and be shown up by Lambda 2 reading zero but why would a plug lead caused misfire make the whole lump run rich?

Guess it will be leads as the next thing to change, tried the air tem sensor first as that was causing a fault to be logged with the ECU, it is better but not quite right since. I know the leads are suseptable to heat and believe me she did get hot under the bonnet when on the rolling road being mapped so it could well be something that simple:-)

Thanks for the advice chaps, your are as ever very helpfull and much appreciated, got to love the Cerb forum.

Edited by gruffalo on Sunday 20th April 00:13