ok so heres my problem. i noticed this when i first bought my truck (about 4k miles ago) under acceleration, and more sever when accelerating from low speeds up a hill, i will press down on the gas pedal and nothing with happen, no gain in rps or mph. then i will feel something near my feet and hear a knock sound then the rear end will sit down and accelerate. when i got my first oil change this problem was completley gone and had no hesitation for about 150 miles then slowley it has come back.

maybe an unrelated problem but when i need to pass or make a light, when i am WOT it takes about a second for the engine to actually "kick in" best way to describe this is if i was racing somebody I would floor it on the 2nd honk not 3rd.

i know it was long but any help would be great.

 

The TPS is definately a good place to start, but there could be more to it... it's hard to say exactly. The pcm takes input from all the sensors to tune the engine, or it could be ignition related.

If you want to test the TPS, turn the key to the "on" position without starting the engine. Then, stick a multimeter in the front (closest to the front of the engine) and middle wires and set the multimeter to DCV. You can stick the prongs of the multimeter right through the insulation in the harness, but it could take some wiggling around to find contact. Fully closed, the optimum position is between .7 and .75 volts, and at WOT it should be close to 4 volts. Check that out and then get back to us.

 

sounds like the atypical slow response our trucks have.

 

well when I have it set to ohms on the prongs of the TPS i can get a reading when its idle and wot but theres a dial for ohm sensitivity not sure how i should set it if thats what i needed to do?

 

I said set the multimeter to DC volts, not ohms! The TPS is a voltage regulator that gets 5 volts from the PCM, and then sends a certain number of volts back to the PCM depending on how far open it is.

 

the only reading i get in DCv is when the red is in the middle plug and the black closest to the fire wall.

 

Ok, thats my bad. I just looked it up in the '01 FSM and they have it backwards from the '95 FSM (I guess they changed it when they switched to OBDII).

So the frontmost (closest to grill) terminal is 5 volts in. The middle terminal is signal to PCM. The rearmost terminal is ground. So if you put the multimeter in the front and rear terminals, you should get a constant 5 volts. If you put it in the middle and rear terminals, you should get a varying voltage depending on throttle position. If you do not get a varying signal, the TPS is bad.

 

thanks for your help man. i can get the constant 5volts and 1volt at idle but nothing registers with various throttle position.

 

i wasnt back probing before but now i got a reading, the tps seems to be working perfectly with no jumping or blank spots win throttle position. my wot was 4v. i was messing around and pulled out the IAT, it looked like it was dipped in tar and solidified. Could this be my problem?

 

no, a dirty IAT will just effect fuel mileage.

ohm out your injectors and make sure they are within spec and within .2 ohms of each other.