throttle postion senser
Thread Starter
3rd Gear
Joined: Apr 2008
Posts: 3
Likes: 0
throttle postion senser
Hey guys I have a 94 Lt1 stock auto. Having trouble with surging acceleration at idle usely only when engine temp is above 210degrees. Thinking it is TPS. But unsure> any feedd back. And if its is it a straight install? or are there adjustments or computer calibtration to be done? Also hesitation at full throttle from 1St to 2nd gear. Again thinking tps . any feedback fustrated!!
Last edited by 94nyvette; Oct 10, 2011 at 11:26 AM.
Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
Rather than throwing parts at it how about an easy way to test it. All you need is a VOM.
1) Set the scale on your meter to OHMS and select the 10,000 or 10K scale.
2) Unplug your TPS
3) On the TPS check from where the gray wire goes to where the black wire goes. You should have somewhere around 5000 Ohms....give or take.
4) On the TPS read the two outer pins. You should read very low ohms. With your leads still attached slowly open the throttle while watching your meter reading. It should smoothly sweep from low ohms (near 0) to high ohms (near 5000). If it jerks and jumps around the TPS is bad. If you don't have the 5000 ohms in test #3 the TPS is bad.
If everything looks fine then chances are the TPS is working perfectly. You can also check it with voltage but Id not recommend that to someone that doesn't do this all the time. Although the chance of an error is slight it is still a chance. This test is completely safe and accurate.
You may consider cleaning the MAF. Use a cotton swab and some electrical contact cleaner. Very gently clean the wires inside the MAF being careful not to break any.
1) Set the scale on your meter to OHMS and select the 10,000 or 10K scale.
2) Unplug your TPS
3) On the TPS check from where the gray wire goes to where the black wire goes. You should have somewhere around 5000 Ohms....give or take.
4) On the TPS read the two outer pins. You should read very low ohms. With your leads still attached slowly open the throttle while watching your meter reading. It should smoothly sweep from low ohms (near 0) to high ohms (near 5000). If it jerks and jumps around the TPS is bad. If you don't have the 5000 ohms in test #3 the TPS is bad.
If everything looks fine then chances are the TPS is working perfectly. You can also check it with voltage but Id not recommend that to someone that doesn't do this all the time. Although the chance of an error is slight it is still a chance. This test is completely safe and accurate.
You may consider cleaning the MAF. Use a cotton swab and some electrical contact cleaner. Very gently clean the wires inside the MAF being careful not to break any.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
I don't like using Digital meters as they will zero out or average the readout. An old analog across the output will jump around if there's wear on the wiper and give you a more definitive result. Of course, I've never seen a TPS go bad, so unless you've got something with a gazillion miles on it, it may well be something else.
Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
Yep, I prefer the analog meters also. Makes it easier to see the needle "sweep". I've actually replaced several bad TPS's. They sometimes open up and give transmission shift problems and stuttering and all kinds of good stuff.
Thread Starter
3rd Gear
Joined: Apr 2008
Posts: 3
Likes: 0
throttle postion senser
Ok , tested the tps with multi meter tested good, heated up engine to 225 to 230 tested good . Swaped out intake air temp sensoer thats in front of mass air flow senser seemed to help but problem returned at about 225 degrees after about 15 mins. Did I mention also installed a new IAC over winter also didn't help. well with out any solid leads I think this problem has meet beat, 
