Boostincx

Been having a problem with my 94 ext cab pickup and its coming down to asking for help from some pro's. It starts up good, idles smooth and revs good all the way until its warmed up and will continue to do so if its just sitting in the driveway. If i take it out for a drive i can usually get a couple miles and it feels pretty good, then all the sudden it bog's down then acts like a rev limiter between 1500-1900 rpm and if i apply more skinny pedal the rpm's slowly decrease, if i pump the pedal fast nothing until it gets back to 1000 rpm's. At first when this problem started i had AFM and knock sensor codes, i replaced the AFM with a "good" used one, got a new knock sensor and sub-harness and welded a nut to the engine lift hook to install outside of the engine. Both those codes went away and still bogging issues but now no codes. I have replaced the AFM, Knock sensor & harness, engine coolant temp sensor, upper intake manifold gasket, TB gasket, Toyota TPS sensor, distributor, PCV valve, fuel filter, NGK O2 sensor, NGK plugs, spark plug wires... still the bogging continues after a couple miles of driving. I just ordered a fuel pump and contemplating ordering a brand new fuel tank as well, when i drop the tank i'll be able to see if there is a bunch of crud getting sucked onto the pump filter when i drive. Any one else have ideas as to why it runs good after it sits for a few days, but after a couple miles driving it starts bogging down and has an imaginary 1500-1900 rpm rev limit? Even if i pull the efi fuse or battery cable resetting the ecu it still has the rev limiter, so its seeming more mechanical than electrical. If i slowly accelerate the truck short shifting under that rpm limit window i can drive it, but if i hit the imaginary rev limit everything cuts out until it gets back to idle... Haven't had a fuel pressure tester on yet everything i read seems like a pain to hook one up to these 3vze's. Another thing to note is absolutely no codes are being stored, when it hits the 1900~limiter the engine light flashes but goes away when it comes down to idle.

fdp101452

You may be on the right track with fuel pressure, but it may not be the pump. If you had enough trash in the tank it might take a few miles to move a clog the screen. With the gas you can get now days at some places, you might find your problem inside the tank.

Boostincx

I was even thinking maybe my vacuum lines were switched or something to where the egr solenoid lines got switched with the fpr solenoid and was switching off vacuum to the fpr when the engine warmed and the egr solenoid switched over. I think I'm just going crazy at this point, all the vacuum lines are 100% correct I've checked them many times over.