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View Full Version : 92 f 150 Q starts and idles but dies with ANY throttle



tri again
08-05-2012, 06:05 PM
same full tanks good gas
same on both tanks

been perfect fothousands of miles

hard to even move it out of the driveway

any thoughts?

thanks

straight 6 automatic

Flossyb20
08-05-2012, 06:19 PM
TPS or mass air flow

tri again
08-05-2012, 06:38 PM
thanks a million

now if the skeeters would find something else to do I could concentrate

rellay rather work on trikes and get into the wind

perrycyn
08-06-2012, 11:32 AM
Could be the coil or the ignition modual. Didnt think 92 had a mass air flow sensor.

fabiodriven
08-06-2012, 12:45 PM
Could be anything. It's next to impossible to diagnose a truck over the internet.

I'll take a stab though. My money's on the fuel pump.

dougspcs
08-06-2012, 01:01 PM
Kinda in the fuel delivery area like Fabio..get your hands on a fuel pressure gauge and hook it onto the fuel rail and see if the pressure is dying out. Being as it's happening on both tanks makes it unlikely to be pump since it would mean both in tank pumps are bad..kinda unlikely. But pressure regular on rail may be stuck or fuel control divertor may be bad..have you replaced your filter any time in the last hundred years?

I think Perry is right, pretty sure the 92 didn't have a mass air..instead they would be equipped with a MAP (manifold air pressure) sensor that performs a similar role.

Have you started with a scan for codes??

Big Mike
08-06-2012, 01:38 PM
TPS is my guess, if you give it any sort of throttle and it dies, I would think the TPS is reading incorrectly and is either cutting fuel completetly or sending too much fuel killing the motor

El Camexican
08-06-2012, 02:01 PM
I had one with a distributor that had seized up and it acted a bit like this because it couldn’t advance or retard. A skipped timing chain can also make some strange things happen. Not sure what shape your engine is in, but if it skipped a tooth when you shut it down the last time (that's when skips usually happen) it won't run right. best check it for play before you lose any hair over less obvious problems. ADD. Mine was a V8 a Ford straight six may not even have a chain as the old ones had gears, but if it has a chain do look at that.

Mosh
08-06-2012, 04:12 PM
Check and make sure the vacumm line going to the MAP sensor has no holes and is connected well at the engine and sensor. Those were big issues back in the day.

Also disconnect the O2 sensor and see if it clears up.If so it is shorted, but generally won't affect fuel control until the truck has been running for a few minutes.
You really need to find someone with an old scanner capable of pulling codes on them old "EEKKK" systems..
AutoZone does not have scanner capabilites pre 1996..


IMO, if one of those 2 things I suggested dont remedy the issue, I would take it to a good tech, pay the 80 check out fee, and replace what he tells you to. I see to many people throw 400$ in parts in a car that don't fix it when it could have been fixed for half that by a good tech.
Like stated, even with a ten minute post of accurate info, many diag jobs on cars/trucks over the net are near impossible.

tri again
08-08-2012, 01:19 AM
TPS or mass air flow

Someone wins a prize for getting the closest.
Flossy b said to check the throttle position sensor and being the rocket scientist that I am,
I took the wrong part off and cleaned it.


It turned out to be the
solenoid on top of the intake manifold that my wrench happened to fit.
at the time.

Guessing it's the IAC or idle air control... a double egg timer
looking sliding electro solenoid looking thing. a little fatter than a #2 pencil
and about 4 inches long, carbon fouled but not stuck at all
and 3 clean harness connections.


the sob fired right up and burned gophers.

I woulda bet my entire trike budget for the entire year that it wasn't that.

Thanks everyone.

Hope summer is wonderful for all.