I have a 2000 dodge 1500 5.9 4x4 that wont go past 2500-3000 rpm even if I press the gas in all the way. When I put it in WOT, the buttefly valve is all the way open too. TPS have been changed, throttle body have been cleaned. Plenum gasket have been replaced, new distributor, spark plugs, wires, fuel injectors, air intake. I even tried replacing both o2 sensor and cat converter. The truck runs fine, no misfire no hestitation on acceleration,idles fine. Once it gets on the highway though, at around 60mph it stays at 1.5k rpm and I cant get it to go further even at WOT. I dont hear any vacuum leak hissing either. If i put it in neutral, max rpm will be around 2500 to 3000. It doesnt seem like there's a rev limiter either.

 

You might want to see what the fuel pressure is.

 

Did you replace the entire distributor? Or just the cap/rotor?

 

Was there the same problem before all of those parts were changed?

I like lookin at the fuel pressure too.

 

The problem was there before I replaced all the parts mentioned above. If it's fuel pressure, what is the correct way to check it and what is the correct PSI I should be recieving? Does the truck have a fuel filter I can change or any other fuel related sensor that could be the issue?

 

You could try removing the pre-cat O2 sensor and see if it improves the engine's performance.

 

Removing the pre-cat O2 sensor didn't help. I don't think my catalytic converter is clogged as I replaced it with a high-flo already.

 

Have you tried testing your TPS?

 

I'm stumped.

 

You need to get a pressure gauge that hooks up to the fuel rail. You be getting 49 psi. The fuel filter is in the tank with the pump.