Results 1 to 3 of 3

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

  1. #1

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

    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?

  2. #2
    Join Date
    Nov 2014
    Ont. Canada


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

  3. #3


    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.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us