1986 ford f150
 

i have a 1986 ford f 150 with a 302 in it. when i drive it and let off an keep it at a steady throttle it cuts out then comes back to life. any ideas what it would be??? thanks

It could be your TPS (Throttle Position Sensor) on the early EFI systems they are real touchy on adjustment. The only adjustment is the idle stop screw and it has to be set to 1.0 volt measured at the center lead. If you can't get it there, then it will need replacing. Do not use an aftermarket, only a Motorcraft one will work correctly!

I would think the first thing to do would be to check the codes, no?

But you (Bill) are an industry expert, so I will defer to your knowledge. :)

Chris, codes may or may not show anything. What he is describing sounds like the nightmare Matt had with his 86, that was one of the symptoms.

thanks guys i will try that

This might help:

Fuel Injection Technical Library » Throttle Position Sensor (TPS)

If you're interested in seeing what the computer has to say:

Fuel Injection Technical Library » How To Run a Self-Test