1988 Ford F-250 v8 7.5L Lose of Power over 2000 RPM
First thanks to anyone that helps me, I dont know how it is here, but I know on a couple forums people dont really like helping people that havent contributed to the forum, but anyway just know your helping a poor man with a broke truck that just wants to go fishing already lol.
I have a 1988 ford f-250, well she starts, idles, and drives fine for about 5 minutes when started, then if the RPMS are brought above 2000 RPM the car will not gain much power and a noise similar to a plastic bag stuck under the car blowing in the wind is heard from under the car. But this problem and noise only occurs above the 2000 RPM.
The car will drive alright if kept under 2000-2200 RPM seemingly with no problems, after it is brought up above 2200 the problem will occur as low as 1500 RPM, when this occurs, turning off the car and restarting causes it to again NOT occur intill the rpm's are above 2000 again.
In park or neautral, the car can be revd above 3K no problems. I have replaced both the fuel pressure regulator and fuel filter.
I dont think its exaugshst cuz i can rev over 2000 in park, I dont think its the TFI module cuz the car idles well warm or cold, I also did a fuel volume test, and it pumped MORE than it should, I havent got a pressure test yet.
When I replaced the fuel filter, it ran perfect for 20 minutes with no problems, and when I replaced the fuel pressure regulator, it drove for 45 minutes over 70MPH and then I parked for 3 hours, dorve 15 more moinutes and then same damn problem.
i hate to say this but ran into that years ago with a different car sounds like there might be something in your fuel tank and when it needs more fuel it plugs the fuel pickup in your tank thats why it only does it while driving and over 2000 rpm.hope that helps.
Agreed. The convertor is either broken up internally or clogged. No load there isn't much air flowing through the engine, once you place a load on it the restriction becomes more apparent. I've seen them get progressively worse as the cat heats up as well.