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T77911S T77911S is offline
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Join Date: Oct 2006
Location: MYR S.C.
Posts: 13,546
if the AFR is too far off it cant correct it.
this can be due to an air leak
wrong control pressure
bad ignition
mixture set incorrectly
or just a bad O2 sensor.

in the end the mixture is controlled be a frequency valve (FV). it is on the back side of the AFM. you should feel it vibrate when the key is turned on.
i dont know how often these fail.

another place to look is under the drivers seat.
there is a computer that conrtols the FV. there is also a speed relay that controls the O2 sensor. this device is known to have solder joint problems. this can also cut off the fuel pumps.

the CD unit gets its power from a delayed action relay. this is the relay that keeps the ignition on after you turn the car off to burn off fuel. i would image it is prone to bad solder joints too.

did you connect the decel valve correctly? personally i would remove this device.

i would check the fuel pressures.
with the O2 not connected, set the mixture to spec.
connect O2 sensor and check AFR's

i would also check the throttle switch to make sure it is adjusted properly.
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Old 11-03-2014, 08:27 AM
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