Copperhead

92 speed-density TPI 383, XFI 280. Fires right up cold but within 3 seconds the CE light flickers on and then goes out, no code set. Starts to run like poop and have to hold the pedal to keep it running for about a minute; then suddenly it will smooth out and settle into its normal lopey low-vacuum idle. Drives perfectly after that.


Any ideas?

aliceempire

iTrader: (14)

Is this a sudden problem or after you made changes? If you made changes, did you retune the ecm? Otherwise, test your CTS.

Copperhead

Done it since it was built. Tuner never had it to work on when it was cold; I drove it over there, cooled it down for a couple of hours, and then he tuned it. I did mention it at the time and he said he couldn't see anything related. Wasn't real gung-ho on tuning the factory setup though -- something a little different but no real groundshaker (he's used to tuning 1000hp turbo builds etc.) Said it was impressive for a TPI but that's about it . . .

What's a CTS?

aliceempire

iTrader: (14)

A Caddilac.....I mean a coolant temperature sensor.

Copperhead

How do you test it?

Tuned Performance

iTrader: (92)

Sounds like you will need to buy a burner and adjust cold start enrichment yourself.

aliceempire

iTrader: (14)

Agreed. Or go ebl, either way, the tuner can get bent.

CTS can be tested with an ohm meter, the table for what ohms at what temperature is on tgo, just search. Tuned even posted it before. I don't think that's your problem though.

Tuned Performance

iTrader: (92)

using tunerpro rt, it would be good to see the blm numbers in closed loop in the 800-1400 rpm range. once the fueling correction has been fine tuned with the ve adjustments then cold start enrichments can be done. If the idle is poor ofter 160F the ecm may not be going into closed loop fast enought due to the o2 sensor not getting hot enough to become active. A heated o2 may solve this, Just throwing out some suggestions

Copperhead

Idles fine after about a minute or so, temp gauge may or may not come off the peg. I have a burner. How do you adjust CSE?

Tuned Performance

iTrader: (92)

Lower down these numbers !

Copperhead

Are those good numbers to look for? Or are those stock parameters? Maybe it doesn't matter on cold start . . . How much to bring them down at once to be noticeable?

Tuned Performance

iTrader: (92)

Those are stock numbers, you might want to highlight the whole table and use the subtract bar setting at the top enter 2 and execute. If you have trouble reading your file feel free to send me a pm I'll walk you through it.

Copperhead

Thanks for your help, I'll have a look when I have time.