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hello
i have an 86 f150 with a efi 302. I have a few problems . When my truck idles it idles then feels like a miss then idles and feels like a miss 5 seconds of idle the one miss. Thats what it feels like anyway. When i am slowing down it clunks when it downshifts, and if i try to keep it at about 30mph the transmission will up##### and downshift alot and feels like the transmission is getting ready to fall out. the truck vibrates at just about any speed. it also will want to overheat in traffic or if i stop for a little bit. I have a few mods on my truck, different from factory not radical. A 160 deg stat, flowmaster exhaust, and the second cat taken out.
Any help is Greatly Appreciated.
Thank you in advance.
The first thing I would do is take out the 160 degree thermostat. It sounds like an innocent modification, but it will really confuse the computer that runs the engine. Take the throttle body off and clean around the throttle butterfly, and the IAC valve which is mounted on the side of the throttle body. Also get a manual and follow the procedure for adjusting the transmission throttle cable. And check the radiator. If it has a bunch of white stuff in it, I would buy a new one.
the radiator is fine I have checked it. I have cleaned the throttle body and the IAC.It still does the same thing but i will have to look up the adjustment on the transmission. I will also get the correct thermostat.
Thank you for your suggestions.
I agree with Franklin on this one. A cool thermostat will definitely upset the computer. How many miles on the tranny fluid? If there's a lot I would drain the converter and the pan, change the filter. See if that helps with the hard shifts.