Manifold Vacuum on a cold engine?
Manifold Vacuum on a cold engine?
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B-Reight

Original Poster:

905 posts

232 months

Wednesday 5th May 2010
quotequote all
The wedge has recently become far to rich at cold idle for reasons unknown, it won't idle unless i give it a touch of throttle which i never used to have to do. CSI is uplugged and i haven't made any changes to the setup.

I've noticed that when the engine is started from cold the fuel pressure registers base fuel pressure, i.e. no vacuum refrence, as the engine warms (2-4 mins or so) the vacuum increases and thus the fuel pressure drops to where it should be. Should i have vacuum right from the instant i start the car or is this normal?


convert

3,757 posts

248 months

Wednesday 5th May 2010
quotequote all
Have you tried replacing the Coolant Temp' sensor?

B-Reight

Original Poster:

905 posts

232 months

Wednesday 5th May 2010
quotequote all
yup, plugged in a spare coolant sensor and there is no change.

B-Reight

Original Poster:

905 posts

232 months

Wednesday 5th May 2010
quotequote all
Mmm thinking about it the lack of vacuum is probably down to the aux air valve being open, probably need to look elsewhere for the problem.

adam quantrill

11,679 posts

272 months

Wednesday 5th May 2010
quotequote all
Disconnect the thermotime sensor which is the easy one to get to next to the coolant temp sensor.