my 4 runner was running like crap, in that it would hesitate, not idle well at all, buck, surge, etc...
I decided that the tps was bad, even though I was not getting any check engine lights at all. I unplugged the tps, and after driving it 3 or 4 times, all negative symptoms are gone, and it idles and drives smooth as silk, im assuming that the computer has adapted/updated its baseline to the signals with tps showing open on all circuits, instead of the erratic signal it must have been receiving with the bad tps plugged in.
glad to find out that it was the tps, because i already bought one.
i just thought it was interesting that i have not gotten any check engine lights, still, with it unplugged.

 

the bulb might have burned out. when you start it do you see a light?

 

yea same here...and no tha bulb is not burnt out...it comes one when i just turn the key to tha on position..i had to unplug my tps just to get my truck to rev past 2000rpm...so yea...

 

I'm kinda curious how you get it to run. I've tried that and the timing doesn't advance properly on mine with it unplugged.

 

If you jump the diagnostic check connectors you'll be getting 1 or both of the TPS codes. 51 & 41.

The check engine light never came on with it unplugged in my 88 either. It ran just fine without it plugged in, just not as good throttle response. I kinda liked the way it drove better before I fixed the TPS 'till I got used to the way it drives with it working right.

 

so the exact same thing as before, happened on my 6 hour trip to virginia, the sensor was unplugged and got the same exact symptoms as before I unplugged it. i plugged in the new tps, and just made it permanently open all the way, and that was the only way to get it to run. i did find some vacuum hose that look suspect, so i am going to look into that.

 

my light is on and its running like crap mine has all the symptoms yours did were is the tps located?

 

Oh-ho...the picture becomes clearer.

The TPS is on the side of the throttle body with four wires going to a plug connected to the sensor.

http://personal.utulsa.edu/~nathan-b...34throttle.pdf

 

My check engine light does come on when starting or when it stalls, so the bulb isn't burned out. Still running strong (yet very rich, obviously) with the tps stuck at WOT. Going to fix the vacuum leaks and issues sometime this week after work one night, will report back with findings.

 

So I found about 5 vacuum hoses that were completely rotted away, I replaced them. I was able to set the TPS not at WOT the way I had it previously,

 

well, at lunch today I took the tach wire off of the igniter wire, and hooked it to the negative side of the coil, and the tach seems to be working much better, don't know if there was just a bad connection to the igniter, or whether that signal is messed up.
also, I blocked off my egr at the manifold, and....i can now mount my tps and using the adjustment there, get it idle fairly smooth. I am sure there are other things going on, ect sensor, cold start timer and injector, etc, etc, but it seems like a bulk of the problem was the egr, it must have been stuck open, or the modulator is bad, dumping too much into the intake.
finally making some progress......