I really need your help

whiner

Member
Joined
Aug 30, 2009
Two more things I am still trying to sort out. When the car is up to operating
temperature at times when slowing down the engine surges almost like someone is cutting the fuel for a split second, this happens from around 25mph down to zero.
Also there is a slight hesitation when acclerate from a stop. My MAF reads 04-05 at idle and climps steadily when acclerate.
Any chance you think it could be the idle air control motor, or even the manifold air temperature sensor as mine is not hooked into the intake it is just plugged in and zipped tied off to the side?
 
Not the air temp sensor. Possibly the IAC. Did this start out of the blue? Had you made any changes prior to this happening?
 
No it has been doing it off and on since I got the car. I have done all the things in my sig just recently. I have also put new plugs, wires, hoses, vacuum hoses, & all new clamps on the car. When I monitor the scanmaster when its doing this the TPS, IAC, BLM, & MAF readings all stay steady. I have also tapped on the MAF sensor at idle and that does not change the idle at all.
 
Stock air flow meter. It is a GM reman that was on the car when I got it.
TPS is .42 key on & .44 engine running at idle. TPS goes to about 420 at WOT.
Fuel pressure is set to 43psi with vac. line off.
I will have to check the IAC I forgot what is was last time I drove it.
:mad::mad::mad:
 
Stock air flow meter. It is a GM reman that was on the car when I got it.
TPS is .42 key on & .44 engine running at idle. TPS goes to about 420 at WOT.
Fuel pressure is set to 43psi with vac. line off.
I will have to check the IAC I forgot what is was last time I drove it.
:mad::mad::mad:

IAC only controls idle so I doubt it's that. Maybe a dead spot in the TPS??
Do some reading at Vortex Buicks
 
IAC only controls idle so I doubt it's that. Maybe a dead spot in the TPS??
Do some reading at Vortex Buicks

IAC controls air into the motor when you lift the pedal to keep it running and also controls how much additional air when you give it a little throttle

Post IAC numbers at hot idle
 
Any number above zero is correct. Typically 15-20 in idle no accessories running.

To lower IAC simply increase throttle blade opening using screw on top of throttlebody. About 1/4-1/2 turn at a time.

Then recheck/reset TPS
 
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