Results 1 to 9 of 9

Thread: LQ4 Won't start

  1. #1

    Default LQ4 Won't start

    I hooked up and installed everything following the quick start guide on my HP EFI. I verified all wires are hooked up properly, firing order is good, I'm reading RPM, everything seems good, but the best I can get is sputtering. It's almost like the timing is off, but when I checked with my light it seemed OK. When running a System Log my cam never changes, it stays at a stagnant range, could that mean I have a bad cam sensor which is causing me not to start?

    When I crank it I usually don't get anything other than cranking, once I've cranked it and there's fuel in the cylinders, I'll usually get a few hits on the cylinders but it won't turn over. Any help would be appreciated. Again, I have spark & fuel.


    After initial cranking:

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,585

    Default

    Which bar MAP sensor is installed, and which base calibration did you use to create your Global File? The base calibration you start with, must correspond to the MAP sensor you're using. Selecting the correct MAP sensor in the Sensors ICF does not rectify the wrong Base Fuel & Timing Tables.
    Ensure all this is correct: http://forums.holley.com/showthread....ents-Read-This (Initial Checks & Adjustments - Read Steps #1-#6!)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2700 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  3. #3

    Default

    I'm using the stock LQ4 MAP sensor which should be a 1 bar. I'm using the LS1 with 4L60E Global File. I went in and deleted the transmission and switched it to HP EFI. I'll have to read through that other post and verify all my info.

    EDIT: To clarify a bit, I have an LQ4 out of a 2003 Suburban, that is stock other than headers, fabricated intake manifold, 102mm Sniper throttle body, and 36 lb/hr Holley injectors. Transmission is a manual. I initially tried the Global File MPI36SB215HE and changed the firing order to the LQ4.

    Small update: I changed my Global File to LS2 and it will startup and run for a couple seconds, but won't idle. I try to give it some throttle and that immediately kills it. I'm working my way through the troubleshooting list and so far so good.

  4. #4
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,585

    Default

    I think it just needs to be tuned. Ensure the ECU is Learning (populating values in Learn Table). Check your Closed Loop/Learn parameters. "Enable Closed Loop" and "Base Fuel Learn Enabled" are the only parameters that need to be check marked.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2700 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  5. #5

    Default

    Quote Originally Posted by k72nova View Post
    I'm using the stock LQ4 MAP sensor which should be a 1 bar. I'm using the LS1 with 4L60E Global File. I went in and deleted the transmission and switched it to HP EFI. I'll have to read through that other post and verify all my info.

    EDIT: To clarify a bit, I have an LQ4 out of a 2003 Suburban, that is stock other than headers, fabricated intake manifold, 102mm Sniper throttle body, and 36 lb/hr Holley injectors. Transmission is a manual. I initially tried the Global File MPI36SB215HE and changed the firing order to the LQ4.

    Small update: I changed my Global File to LS2 and it will startup and run for a couple seconds, but won't idle. I try to give it some throttle and that immediately kills it. I'm working my way through the troubleshooting list and so far so good.
    Try increasing the fuel on the Base Fuel Table in the idle area a little at a time. Sounds like your starving it. I found that when I switched from the truck intake to the Holley Hi-Ram it took a little more fuel. I would also check you injector data and make sure it matches. Those injectors should be easy to find info for.

  6. #6

    Default

    I'll try that when I get home, I appreciate the info. Luckily the injector data is already loaded, since they're Holley injectors.

  7. #7
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,585

    Default

    Smart purchase.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2700 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  8. #8

    Default

    This is embarrassing, but I got the car started. I had an oil leak and took a few days to get it situated, then decided to wait because I didn't have a fuel pressure sending unit on the car. I figured I'd wait for that to come in, hook it up then call Holley and see how they could help me. I hooked up the fuel pressure unit and turned the key, 0 PSI, I thought maybe I have the wrong sending unit selected, verified. Then decided to just unhook the fuel line up front and turn on the pump. No Fuel. So I decided to unhook my fuel lines from my WIX and it turns out somehow I crossed my return and supply lines. I swapped them and it fired immediately. I've been fighting this thing for a week now and it was all over a crossed line. Embarrassing, but these things happen.

    I didn't think it was fuel since I was smelling it and since the engine would fire and just not idle. Moral of the story kids, just because you can smell fuel, doesn't mean you're getting it.

    Danny, thank you for the links and spending time on here helping out. And Turbo_c10, you were right about it being starved of fuel.

  9. #9
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,585

    Default

    Quote Originally Posted by k72nova View Post
    Danny, thank you for the links and spending time on here helping out.
    You're welcome. I'm glad you found the problem.

    And Turbo_c10, you were right about it being starved of fuel.
    Yeah, it really wasn't getting any fuel.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2700 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

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