1986 EFI F150 problems

Truck hesitates, barely accelerates, and dies when warm.

My 86 Ford has been giving me a lot of trouble. So far I have cleaned the carbon out of the throttle body and IAC valve, and also tested the IAC, and the lines and filters are fine. Only oddity I could find is these weird plastic hollow tubes that are near the battery and fuel pressure regulator that are really brittle, and someone has broken several of them. It will start fine if it has been sitting, and with a little pressure on the gas pedal, but after running for a couple minutes it bogs down until dying, and eventually will barely crank, all when the engine reaches about a quarter of it's normal operating temp. I have heard everything from cam position sensors to PCV valves, O2 sensors, and fuel pressure regulators, and now I'm more confused than ever. I suspect the throttle position sensor is not correctly set, and when reading the codes it says it is set too low, and that the throttle stop is too high, among other things such as the EGR, EVP, coolant temp sensor, and idle speed controller. Where on earth should I start? Who is right and who is wrong? How do I adjust the sensors?
Any help or info would be much appreciated.

Regards, Seth

Comments
No. 1-2
SethC
SethC

Thank you! Will definitely look into that.

ScottyKilmer
ScottyKilmer

Editor

start with a new thermostat, running too cold can cause all that. Then check for vacuum leaks on that old thing, very common. https://www.youtube.com/watch?v=zMok2y05jNE

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