I have an 88 TII and I just bought a new TPS from mazda and installed it.

My problem is:
I use the volt method and the light method to set it.

Looks right.....

Drive the car and check it again and it is always off!!!!!

Even though it is off I don't seem to suffer any ill effects. Car runs great and idles great...WTF

Can anyone suggest what might be wrong.


Thanks
steve

 

you need to set it hot, go run it around the block a few times and then set it

mike

 

Thanks for the advice but I only check it when it is hot.

 

How far off does it get at idle?

 

I did notice something weird happening when I checked the car using one volt method when it was running.

I connected the voltmeter to the green wire on the TPS and the battery ground, then let the car run and the meter steadily decreased voltage.(.9 & below) Should it do that? Am I doing something wrong?

Then turned off the car and checked it with the ignition on but not running and the voltage was where I set it(near 1v)

 

I can't check it with the engine running (TII w/ stock intercooler) so I don't know what it would do, but if you're staying around 1V with the car off and the key on, you should be all set.

 

The problem I am having is I can check it the next day and it will have to be readjusted again. It never seems to stay adjusted properly.

 

Rochsteve.....it sounds to me, when you see the voltage decrease while the engine is running, that the engine was not truly hot when the tps was set. The trait that you describe is a fast idle cam still riding on the roll pin and slowly coming off it. Next time, if you use the one volt method, do it while the car is running and fully warmed up. Check it the next day under the same conditions and see what it reads. I'll bet it does not vary from one volt by more than down to 0.95 and a high of 1.00 volts. If you use the two light method I'd suggest following the rules and turning the engine off for that.