fusion-turbo

Hey guys i tried doing a search for this but came up empty handed. When my car is cold after just being started i cant move it for a good 3-4 minutes or so or else it will instantly stall, then while the car is warming up to normal operating temp it will randomly "hesitate" for 2 or 3 seconds at a time. it doesnt matter if im accelerating or staying at a steady rpm, and then it will kick back in like nothing ever happened. And after the car is warmed up it stops... and it also feels like it has less power after its warm than when it was cold. Any ideas?

pyrojunkie

I recently had some bad hesitation issues fixed by replacing the TPS. I would recommend checking it and then adjusting or worst case replace it.

SureShot

Using test lights or voltage at idle readings will get your idle setting perfect, but you could still have a worn out TPS resistor.
-The golden test:
Pull the TPS connector off.
Get an analog (needle type) VOM set to the 1K scale.
Connect it to the pins for the orange & green wires.
Open the throttle enough so you can test the TPS plunger through its full stroke.

As you work the TPS plunger in & out, the meter needle must swing smoothly from ~0 to ~5K ohms.

As the TPS wears, it can give non-linear or inconsistent signals to the ECU.
A worn out TPS may give 1K ohms at idle, but have a drop out or short further up the scale.
A drop out at mid scale will tell the ECU to idle at that point & give a fuel cut hesitation.
I had one go open at the top which made the S5 ECU go nuts, giving random fuel cuts.

fusion-turbo

I guess that could also explain (what seems like) a loss of power at Norm. Opp. temp. as opposed to still being cold. Is it possible that my TPS is giving a slightly wrong signature to the ECU at n.o.t. resulting in less performance?

cwsttu

you have that saved on your computer dont you.. i know you dont type that out the 500 times i see it every week word for word thanks for the reply in my thread a couple of weeks ago my tps tested fine after trying this

christopher

SureShot

Yup- I have my own little FAQ document for frequently replying to FAQ's.

fusion-turbo

i just checked the orange and green wires on the tps with a digital multi-meter, and i got a approx. reading of 3.5k ohms, and as i opened the throttle up it decreased to about 1k- 800 ohms... isnt it supposed to increase resistance when you open the throttle up more? Thanks!

fusion-turbo

Problem is getting worse as time goes on, i have another TPS off the old (american version) blown engine, should i try swaping it out even though this is the J-spec engine? any ideas would be helpfull!

opelbits

iTrader: (5)

Bad temp sensors may cause something similiar. I had a problem a couple of years ago with the car running like crap for 5 to 10 minutes cold. When warm, no problem.

Turned out to be either the temp sensor on the backside of the water pump, or the sensor on the bottom driver's side of the radiator. (S4 GXL)

SureShot

All the 2nd gen RX-7's use the same 0-5K plunger type resistor.
The brackets vary among models, but the black plunger unit is the same.
When reusing your bracket, you may need a VOM to tell which wires to splice to the plug if the colors don't match.

2x88GXL

Have you ever done the 3800 RPM acceleration bug fix on your 7?
If so, I'd say it could be any number of things... otherwise i'd do that first

fusion-turbo

I have done the 3800 rpm fix, and also did the grounding how-to, but i checked out my tps and im only getting a reading of about 3.5k ohms to 1k ohms.. its not going up to 5k ohms like that last write up

fusion-turbo

ok, i replaced the TPS and im still getting the same problem, just a random cut in throttle. I also noticed that i can still hear my turbo boosting while i have this throttle cut, but i know that makes no sense. No ignition= no exhaust= no turbo boost. Im out of ideas so if anyone can pull anything out of their box-o-tricks it would be very appreciated!