Just got a 6yr build on the road. Used to have a tuned E6K, but upgraded to the Sprint. Overall I am very happy, but after about 60 mile, a intermittent
problem arose. Problem was short lived, but came and went several times. ECU is dumping fuel on the motor. Wide-band pegged down to 10:1 (might have been lower) and even stalled a few time going down the highway. Seamed to correct itself then went back to going super rich.

Later, I got a laptop hooked up. TPS signal was all over the place while it was doing this, then suddenly TPS signal went back to normal, but still rich.
Laptop died before I could run a data log. Car is being prepped for a show, so no driving till monday.

What should I check besides TPS??
Correction map way off somewhere??
What could be going on here??? A flooded rotary is no fun.


Im using the supplied 13bT S5 Map that came with the ecu; Starts and idles very well. Haven't boosted yet, as I'm still shaking down the chassis. Any help is appreciated, thanks

 

If the raw readings from the TPS are all over the place in the datalog without the throttle being touched then you either have an electrical issue (TPS ground, TPS signal wire floating/intermittent) or a bad TPS.

 

I plan to test the TPS, but how would that cause such a rich condition? Throttle pump?

 

S4 or S5 TPS?

 

Its the TPS from my old E6K system. I think its a GM type.

 

Those are notoriously flaky. Run a log while it's acting up and watch TPS and transient fueling. If the sensor gives a jittery reading at all, the ECU thinks you're constantly requesting transient fueling and you get a rich condition.

 

Right, thanks. Pulling it in the shop now.

 

any idea what the GM part number is for it? I work at a Chevy dealer

 

Removed and remounted the sensor. Also checked and adjusted timing. Running great now.

But I still think a new TPS sensor is in order. Is there one that fits particularly well on the S5 engine?

I found a few GM ones that might work that run in the $60 range.

 

The stock S5 sensor fits amazingly well and works.

 

I have my bell crank and throttle cable where the original TPS would be.

 

Air pocket in the coolant system would also give a false temp reading.