I bought a1994 f150 awhile ago, it's a 4x4 4.9L L6 with an E4OD trans and I've had some problems with it, if you want any more information or a list of the sensors I've replaced just ask. It starts fine, but after that it idles really high until I tap the gas. If I rev it up while it's running it'll drop back down to a lower rpm and die. It also dies when I take my foot off the gas when I come to a stop sign or something like that. I've replaced quite a few sensors but I get the feeling that I might need to replace the ECM. I'm gonna try replacing the vapor canister purge Valve next.
​​​​​ If you have any suggestions for me to try or things I could do please let me know.

 

slow the parts replacement until you diagnose the problem.

TPS checked?
IAC checked?
Fuel Pressure checked?

ECM on hold..the symptoms just don't support this be replaced.

 

Does your oil pressure gauge work properly? If you have low oil pressure, your fuel pump(s) may shut off.

I had the same issue with a previous truck (‘91 Silverado 350). When the engine was cold it had sufficient oil pressure in all conditions. However, when the engine warmed up the truck would die at stop lights or just when coming to a complete stop in general when I did not give it a little gas to keep the RPMs up higher. Ended up being worn main bearings after having it torn down.

Just my two cents and something worth looking at real quick. Hope you get it figured out soon

 

Yes, my brother owned this truck before me and tells me that he replaced and checked all of those things. But still the same problems
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