Hello all!

I recently bought a 1992 F-150 reg cab short box inline 6cyl and am having some issues with it. the first week of driving it the timing gears went in it which was no big deal for me to fix. Now I am chasing a stumble on it and am at a loss as I am not very familiar with fuel injection systems. It seems to stumble more when it is at normal operating temp then when it is cold. It also seems to do it more after I have had it in gear down a long hill without giving much gas. Once I give it a little throttle it stumbles then hesitates a bit and takes off normally one I give it a good amount of throttle. Always Idles fine however. I've started by replacing the plugs ect. and the TPS and dont really know where to go from there. Any suggestions or possible problems would be much apriciated! PS I would attach some pics of the truck but cant seem to figure out how......

 

go to Ford Fuel Injection and learn how to pull your codes... then let us know what you have

 

I had it pluggedin and it told me that the voltage was too low for the TPS or the acceleration sensor. I replaced the TPS and it is still giving me the same code so I'm not too sure on what I should check/replace next.

 

no idea i don't mess with fuel injection but this will give you a bump so maybe someone can help you who knows what they are talking about

 

Did you clear the stored codes by disconecting the battery for 15 minutes before you tested again?

 

+1

Also clean/soak the throttle body with carb spray.

 

Yes codes were cleared twice but still seems to be tossing the same one at me. I will try cleaning up the throttle body with cleaner although it doesn't look too bad.

 

bump bump bump

 

Yank out that tried and ture 300 I6 and drop in a belly button SBC.

Here's a bump for you anyway.

 

I thought you had to use throttle body cleaner that was safe for sensors. I still use carb cleaner to check for vacuum leaks,but not for cleaning.

 

I would agree with this one. Carb cleaner as I understand it, can leave a slight oily residue which can contaminate sensors. As for the TPS voltage, there is some degree of adjustability on these...have to measure at the TB for range, etc to confirm the reading....thinking it is somewhere between .6 and 1 V but not over, at idle, and up to 5.5V at full throttle opening. IIRC, computer uses this to determine mechanical idle speed and compensates with IAC valve accordingly. www.fordfuelinjection.com can explain its function and adjustment.