Throttle position sensor
Throttle position sensor
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GTOBEN

Original Poster:

90 posts

232 months

Wednesday 7th May 2008
quotequote all
Hi all. The quest to get my cerb running right continues. I have recently had the engine balanced and its running much better and smoother. I do however still have a problem that when the revs drop from high (i.e. changing gear) they fall below idle and the engine stalls. This doesnt happen when the engine is started up or left on idle, only when the revs are high and left to drop. Its making it virtually undrivable and i need three feet to keep the engine revs up.
The lambda sensors seem fine and i suspect the throttle position sensor? Has anyone else had this problem? And where do i find that sensor?
All suggestions appreciated as i just want to get out in the sunny weather! Thanks

FarmyardPants

4,379 posts

248 months

Wednesday 7th May 2008
quotequote all
You could try turning up the idle screw a bit. This controls how far the throttles close. Remove the cover and there's an 8mm bolt under the throttle cable carrier that you could undo a few turns and wd40 the mechanism. Worth a try.

GTOBEN

Original Poster:

90 posts

232 months

Wednesday 7th May 2008
quotequote all
Thanks but i have tried that. The engine then sits at 1500 rpm on tick over! Not ideal. It must be something to do with whatever controls the idle.?

FarmyardPants

4,379 posts

248 months

Wednesday 7th May 2008
quotequote all
Likely a TPS problem then as you say. Need to hook up a laptop to see which one(s).

GTOBEN

Original Poster:

90 posts

232 months

Wednesday 7th May 2008
quotequote all
I have just managed to get my laptop to connect in the last few days so am a bit of a novice. What / where do i look?

marcus1970

1,217 posts

265 months

Thursday 8th May 2008
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GTOBEN said:
I have just managed to get my laptop to connect in the last few days so am a bit of a novice. What / where do i look?
Throttle pot readings.

Should be around 15'ish, then rise evenly upto around 92'ish on full throttle.

Usually, if they rise together then they are ok, but if one jumps about giving spurious readings, it's probably time for a new one.

MB