This is what my car is doing.
From a cold start, the RPMs will bounce up and down from 1500 to about 1700-1800 till it warms up all the way.
Once it warms up the idle will drop to aprox. 900 where it stays relativly smooth.
If you bring the throttle up to 1500 it starts its bounceing again and it will continue to do this till you get to 3k rpm.

I have run a ground from the throttle body to the chassis, and another from each coil to the battery, and yet another from the intake to the battery as well.
that fixed a diffrent problem I was haveing.

I allso changed out the TPS with one from another engine, But I do not know how good of shape it was in.
I keep seeing references to ajusting the TPS in all the searches I did On this forum but nowhere does it say HOW to ajust the damn thing. Unlike allmost every other car I have worked on I cannot see any obvouse way to ajust this thing.
I did read in another forum to goto teamfc3s.org but half of their damn links are bad, namly to their FAQ section where it aledgedly tells you how to do this.

Any Ideas other than ajusting the TPS and instructions to ajust the TPS are welcome Please.

Thanks.

 

Guess it would help if i gave you a little info on the car itself.
its a 1986 GXL non turbo

 

The cold start thing is part of the accelerated warm up system and can be eliminated if it bothers you by removing the cold start thermo wax. Instructions for adjusting the tps can be found at www.fc3spro.com same with instructions on the tb mod / cold start thermo wax removal.

 

bah bad post

 

ok turning the little screw did not do much except to get my TPS at 1k ohm that had no effect on the problem I am haveing.
maybe I did'nt explain the issue well enough.
ok it does what I said above about the surging till it warms up. Then the idle drops done like it is suppose to and it smooths out. BUT if you try to hold the throttle anywhere from its idle up to about 3krpm it starts doing its little bouncy **** till you clear past it, the the car runs like a bat out of hell.
And NO keeping above 3k rpm is not an option there are shitloads of idiot kids whos idiot parents let them play in the street here.

Is it possible that the "accelerated warm up system" is being stuck "ON"???

I tried to find that removal instructions you mentioned with no luck... I suck..

 

I have posted the TPS adjustment procedure many times...2nd hit on a search for "tps adjust":

https://www.rx7club.com/showthread.p...ght=tps+adjust

Have fun.

 

Anyways, Like I Said its NOT the Tps
And I allready ajusted it.

plus I was doing my search in "THIS" section and that provided me with the same info you posted.

But thanks anyways.

Now does anyone have any Ideas what is causeing this?
If I need to I will go out and make a recording of it.

 

Ok. Your car is doing the SAME thing mine is. However if you let your car sit and warm up for about 5min. It should turn off.
Try re-reading the guide and seeing if you missed something for adjusting it. Im not bothering taking mine off because I just let it sit and warm up.

 

take your TPS out and hook an Ohm meter to it, slowly slide the pluger all the way in and watch the ohm meter. ther is most likely a dead spot in the sensor. get another one...

 

yeah did that allready and I sprayed EVERYTHING down with wd40 and found no vacume leaks either

 

I had bouncing Idle once, i spent about an hour or so adjusting the throttle position, throttle cable and idle, finally got it stable. What REALLY made my idle very smooth and steady is premixing, it turns out my car wasn't getting enough oil to the rotors so it was running poorly. You might check for oil leeks on your OMP and oil injection lines.

 

No leaks

Next

 

You need to adjust the TPS properly. The voltmeter and "light" method are crap. Don't waste your time with them.

Your symptoms are exactly those of a bad TPS...Hows the actual TPS plug? Have you checked the resistance of the TPS throughout it's entire sweep with an analog ohmmeter? Wires from the TPS to the ECU?

It can also be caused by a vacuum leak. Don't waste time trying to find it. Just pull your upper intake, replace every hose, then put it back using gasket sealer.

Might also be a BAC valve thats sticking. Pull it, clean, reinstall with new gasket and sealer.

 

Ok I say say with certainty its Not a:
Ground Issue
Vacume leak
TPS Sensor
ECU
BAC

I have added a few groumnd to the just about everything makeing sure that was not it.
I Created a controled vacume leak to try to immatate the problem, Thats a totaly diffrent thing that happens when you have a vacume leak.
I have changed out the TPS with two known goods.
After starting and running them still had same problem.
tried to reajust them. no diffrence other than idle rpm.
Changed out the ECU with a known good one and ran a ground to it form the battery.
Changed out the BAC.
Then later blocked it off.

the damn thing is acting like it is getting a fuel surge.
could the injectors be going bad?

 

oh yes I did check the entire range of all three TSP and all checked out fine.

i am getting very frustrated with this and am about to say to hell with it and go carberated.

 

you might wanna mess with the adjustment screws on the TB. i had the same problem, mess with each one of them, seeing what they do. just make sure that you only mess with one at a time and remember how everything was to begin with.

 

Ok I beleive i have FOUND the problem.
Funny thing is I decided to hell with it I was going to pull ALL of the EFI Crap off and just slap a carberator on it.
Well Whill i was removeing the uper manifold And started to pull off the primary injectors, I noticed a rather larg glob of melted plastic on top of one of the injectors, The wires were not melted all the way through as far as I can tell but they were crispy enough that the insalation was very brittle, So i am thinking that it was a week barrior like I high ohm resistor and there was voltage bleed through causeing the ECU to freek out.
Everything else looked and tested out fine.

Thank for everyones input.
Thanks for the suggestion in the PM Chris.
I'll remember that when I start going back together with the EFI parts off my blown moter.

I'll let everyone one know in the next few days, (depending on how lazy I am and the weather)

thanks

 

That's not correct. The AWS and thermowax are completely unrelated, and perform two different functions.