ghost-rider

Well it's been one problem after another, now I'm back to the tps again. About a month ago I went through most of the treads about tps on here and I was finally able to adjust it and the car had perfect idle, now everything is screwd up again and I haven't touched anything. I went to check the fuses yesterday because the coolant temps are slightly higher, but thats due to the fmic, anyway, I pulled the fan fuse under the hood and put it back in, went to check the fusebox inside, above the foot rest on the driver's side, pulled out a couple of fuses, checked, put them back in and the fans come on at low speed, wtf???

Today in the morning, I started the car and as soon as it warmed up, it started idling like an untuned single turbo motor that's always in the videos on streetfire. Went to school, and it was painful. At first it was fine, then rpm droped to 500 and when I try to drive it holding the accelerator pedal steady, the car acts like if I were to put the pedal to the floor for a second and completely release it, then after a while it would settle down, then everything repeats again. Finally on the way back it started happening more often and I had to get her towed home. It looks like it happens when the fans come on and settles down when they go off. It tends to settle down if I raise the rpms a little until the air pump comes up, then it idles at aroud 800rpm. I checked the tps again and the bottom (black) wire reads fine, but the top (green) wire reads 12.04v and it increases as I open the plates. What does this mean? I have yet to find a thread where someone had a tps reading of 12v.

twisted7

iTrader: (3)

make sure it is still within spec. Damian put up a very good post on how to adjust it properly.
https://www.rx7club.com/showthread.p...o+more+bucking

ghost-rider

Thanks twisted7, I used those instructions the first time and got the tps within spec. It was within spec until today, now the bottom wire is .5v so that's ok and the top wire is showing 12.04v thats a problem b/c it's supposed to be around 1.00v. How can one range be ok and the other so far off? Is that even possible, I thought that both ranges are supposed stay close to each other. I'll try to adjust it again tomorrow and see what happens. Why did it screw up so badly? i haven't been doing nything near the tps for the last month or so and the car has been running perfect.

ghost-rider

any help will be greatly appreciated, I need to get the car back in order as soon as possible, and I'm open to any suggestions at this point. Could the tps sensor itself be damaged, something inside of it burned or shorted?

dgeesaman

iTrader: (7)

I don't think the TPS is supposed to get more than 5v input. (please verify with the FSM but I'm pretty sure of that). If your'e getting 12v, it's either your ECU gone bad or wiring that's shorted against a 12v line. If thats' the case you might be due for a new wiring harness.

Dave

wstrohm

According to my '94 FSM:

1) terminal 3I of PCME (brown/violet wire at TPS) should always be at 5.0 volts.
2) terminal 4D of PCME (brown/black wire at TPS) should always be at 0 volts (ground).
3) terminal 3F of PCME (green/red wire at TPS) should be at 0.75 - 1.25 volts with accelerator pedal released, and at 4.8 - 5.0 volts with pedal fully down (after warmup, ignition switch ON).
4) terminal 3G of PCME (black/green wire at TPS) should be at 0.1 - 0.7 volts with accelerator pedal released, and at 4.2 - 4.6 volts with pedal fully down (after warmup, ignition switch ON).

oilrag22

Yep it is not good, having a 12V on your TPS. TPS works with 5V and less. So check if your 12V wire, is getting 12V through faulthy wiring.

You've got pm... to troubleshoot TPS