Symptoms of a bad Throttle Postion Sensor?

[TheTSiGuy]

Problem.

As of lately, ive been experiencing loss of power, a little bit of sputtering, and some bucking.

Plugs are new NGK's gapped to .28 ... about 4000 miles ago. Wires are relatively new as well i think.

Other things such as the fuel filter were changed within the last 10,000 miles.

I have no clue what it is. The funny thing is, it comes and goes. Say i want to take off from a stoplight. sometimes it will bog down in first, and accelerate so so so slow. othertimes, it comes close to normal. boost is VERY slow to build up. in 1st gear, its like i hit a brick wall. 2nd has some power, 3rd and 4th are mostly ok.

Ive heard that the TPS tends to go bad on 1g's. Maybe mine has? i have no CEL's.

Any ideas?

 

[TheTSiGuy]

Nobody know eh?

 

[aleccolin]

Yeah, I'd like to know too.

 

[TheTSiGuy]

Apparently the TPS may be ominous.

Im going to try to swap another one in. Judging by what the TPS does (sees and determine what the ECU should do due to throttle positon) i believe that it may have gone bad. From what ive gathered from the rest of the internet, the symptoms (seemingly 20% throttle at WOT) seem to be consistent with the piece.

I'll attempt to swap a new unit in and see what it is. Haynes doesnt have much to say either.

 

[teme]

test your tps:

Testing Procedure:
(1) Test the resistance between pins 1 and 4.
The resistance should measure 3500 - 6500 ohms

(2) Measure the resistance between pins 2 and 4 while rotating the throttle open. The resistance should change smoothly.

(taken from http://www.geocities.com/MotorCity/Downs/7678/dsmtests.html )

 

[TheTSiGuy]

Thank you Teme. thats been the most useful info yet.

My buddy also has a datalogger..maybe i can get it on my car to test things out. i'll keep you guys informed!

 

[Chuck_3]

a couple symtoms i found are: a faulty tps could cause poor acceleration or possible spark knock

if you hav an ohmmeter you can test the tps

first disconnect the tps's electrical connector, connect the ohmmeter to the sensors input and output leads. then slowly open the throttle and watch your meter. the reading should increase smoothly without jumping or skipping. if it jumps or skips the tps is bad.

also a typical tps voltage can be from 0.2 volts fully closed up to 5.0 volts at wot

 

[TheTSiGuy]

how do i slowly open my throttle? using the throttle cable?

I read its resistence at rest. 4.83 volts. guess it might not be my problem. I have yet to check its resistnace while opening my throttle

Back to the garage..

 

[TheTSiGuy]

Ok, back from the garage.

Unfortunately, TPS is not my problem. i checked its resistance at still, and check it while opening the throttle. everything is perfect with that.

Which means my problem lies elsewhere....

::sigh:::

 

[Chuck_3]

yah you could use the cable or hav a buddy do it with the pedal in the car