Constant backfiring, stumble & stall. Will not maintain idle.

[Scott Schoelen]

I've had this Terminator EFI system installed for about a year and a half now, only about 1500 miles on it. My Blazer was running great, and after a day of running it pretty hard at the dunes, while driving on the freeway home about 75 miles into the trip, it started backfiring & losing power. The more I pressed the gas pedal the worse it would backfire. I could no longer maintain speed and had to pull off the freeway. I cleaned the distributor cap tried again and it ran well for about a mile, then the same thing. After towing it home I replace the cap, rotor & control module on the distributor and still the same thing. Sometimes it's hard to start now, and sometimes it fires right up. Sometimes I can get a nice idle for short periods of time then it stumbles stalls. Sometimes it won't idle good at all. What could cause this? While I was driving down the freeway, everything was great. I'm new to all the EFI stuff. I tried emailing a Holley Tech. We emailed back & forth. He asked me to send a datalog, so I bought the overpriced cable & tried, but get a communication error with the laptop. I emailed him back and never got a response back from him, even after multiple attempts. I have tried multiple times now to email a tech again, and I cannot get a response from them. I was once very happy with this EFI system and Holley Tech Support, and the help they gave during the install, but now that I'm past warranty I feel that they don't care. Does anyone have any ideas?

[81 TransAm]

Do you have the 3.5" Touchscreen? You can internally datalog & transfer it to the SD card.

[Scott Schoelen]

Yes, I do. I will try that as soon as I get a chance, it might be a couple days before I can try or figure it out. Thank you.

UPDATE: Got it going! Thanks to Richard Nedbal of Fast Man EFI. It was all in the programing. Did not have to replace any parts.