sputtering when cold

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boogeyman

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my 92 mtx has a issue when i jump in after its sat for a while and cooled off it spits and sputters under 4k untill it warm up ive done a TPS sensor ,plugs,wires, dis module but am starting to suspect the crank pos sensor is bad i read someplace that it can cause it to run poorly when cold and clears up once warm. any idea`s it runs perfectly fine once warmed up for a few minutes
and i also noticed it smells very rich when first started and is quite loud if i apply any throttle to it

i get no codes from it for anything.
 

boogeyman

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no it has cats on it. im realyl strting to think the o2 sensors are shot. if they were warming up as intended it should run clean no matter how long it has been running correct ?
 
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rubydist

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crank sensor will not give you that symptom.

clean the mafs would be my first step. when was the last time you changed the air filter?

the engine is running open loop when first started and it sounds like that is your issue - the pcm is not getting the correct reading on how much air is getting into the engine, therefore a/f is off. once it gets to closed loop, the pcm can correct for the bad reading.
 

boogeyman

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i swapped in a fresh factory filter just to try it no dice same thing. i know that upon startup the car is in a sort of limp mode for 255 seconds until the computor figures out what all the sensors are telling it. im pretty solid when it comes to the ford eec-iv system but this thing is driving me nuts with no codes and the odd way it acts. i think this weekend im gonna try the 02 sensors and see if that helps

on a side note if i start the car from cold run it down the street and back and pull the front 3 plugs they are all moist and blackish telling me that it is running rich as **** the timing band is perfect on them so i know its not ignition related
 

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