Stalling when I let off the gas
#1
Drifting
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Hi Guys,
Finally got my AFPR installed last night. I expected to have to play around with the MAF settings a bit, but I've still got a problem.
When the car is warmed up, I can sit in the parking lot, give it about 3000RPM, and then back off totally. The car then stalls!!! Obviously, it's the same at lights, and I know it will start being a drain on the batteru when I have to keep starting it up again.
So, I've set the FP to 35PSI, and when I look at the settings on my MAF (Lindsey), then both dials are cranked up on the pretty rich side. The AFM Indicates something stupid, 'cos I think I connected up the 4 wire O2 sensor a bit wrong, so that's no help yet.
Normally, I would take that stalling to be a sign of being too lean, but with the settings up as they are, I can't see it.....
Any ideas out there???
Thanks,
Finally got my AFPR installed last night. I expected to have to play around with the MAF settings a bit, but I've still got a problem.
When the car is warmed up, I can sit in the parking lot, give it about 3000RPM, and then back off totally. The car then stalls!!! Obviously, it's the same at lights, and I know it will start being a drain on the batteru when I have to keep starting it up again.
So, I've set the FP to 35PSI, and when I look at the settings on my MAF (Lindsey), then both dials are cranked up on the pretty rich side. The AFM Indicates something stupid, 'cos I think I connected up the 4 wire O2 sensor a bit wrong, so that's no help yet.
Normally, I would take that stalling to be a sign of being too lean, but with the settings up as they are, I can't see it.....
Any ideas out there???
Thanks,
#2
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sounds like you *could* be running rich and when the throttle closes in the instant before the computer updates the injector duty cycle it stalls... but thats a long shot. usually it would keep running even if it's running really rich. try hooking up the a/f meter and make sure it's working, then lean it out as much as it needs to be and try again. if that doesnt work try swapping the dme with one you know works, dme's going bad tend to do bad things like this.
#3
Race Director
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Sounds like you have a couple of things that are going wrong. So you might want to fix them all since it may be the combination and not a single fault here.
"So, I've set the FP to 35PSI, and when I look at the settings on my MAF (Lindsey), then both dials are cranked up on the pretty rich side."
Try for a little more fuel-pressure (40-45psi) and return the adjustment dials closer to zero-adjustment. The way you have it set will cause you to hit 100% injector duty-cycle early.
"The AFM Indicates something stupid, 'cos I think I connected up the 4 wire O2 sensor a bit wrong, so that's no help yet."
What's "stupid" mean? If you're seeing erroneous AF-ratios on the meter, then most likely your DME is seeing "stupid" readings too. How do you have your O2-sensor wired?
"So, I've set the FP to 35PSI, and when I look at the settings on my MAF (Lindsey), then both dials are cranked up on the pretty rich side."
Try for a little more fuel-pressure (40-45psi) and return the adjustment dials closer to zero-adjustment. The way you have it set will cause you to hit 100% injector duty-cycle early.
"The AFM Indicates something stupid, 'cos I think I connected up the 4 wire O2 sensor a bit wrong, so that's no help yet."
What's "stupid" mean? If you're seeing erroneous AF-ratios on the meter, then most likely your DME is seeing "stupid" readings too. How do you have your O2-sensor wired?
#4
Drifting
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I bought the 4-wire universal sensor from Paragon. I connected:
White to white (duh!!!)
Black to black
Grey to black
and Black to batt-
(I think... I'll have a look on the car later!)
I know I got the instructions (?) from here on the Huntley 4-wire sensor, and connected it like that!
The AFM always indicates around 16.0. I suppose that could mean, if the MDE's getting the same thing, that it always thinks it's running lean??
Anyway, a bit of an update... When I was driving home last night (Through town), when the car warmed up a bit, I noticed that it had a very unstable idle speed. Will the idle speed regulator affect things when it's NOT at idle aswell.
I had the intake off after that to see what could be done, and while I was in there, I cleaned up the Throttle body nicely, and had a check on the Vacuum connections (all seemed OK).
Does anyone know the connection to the 4-wire sensor? I'm getting the feeling that's it!?
Thanks
White to white (duh!!!)
Black to black
Grey to black
and Black to batt-
(I think... I'll have a look on the car later!)
I know I got the instructions (?) from here on the Huntley 4-wire sensor, and connected it like that!
The AFM always indicates around 16.0. I suppose that could mean, if the MDE's getting the same thing, that it always thinks it's running lean??
Anyway, a bit of an update... When I was driving home last night (Through town), when the car warmed up a bit, I noticed that it had a very unstable idle speed. Will the idle speed regulator affect things when it's NOT at idle aswell.
I had the intake off after that to see what could be done, and while I was in there, I cleaned up the Throttle body nicely, and had a check on the Vacuum connections (all seemed OK).
Does anyone know the connection to the 4-wire sensor? I'm getting the feeling that's it!?
Thanks