Page 1 of 2 12 LastLast
Results 1 to 10 of 16

Thread: Completely Lost

  1. #1

    Default Completely Lost

    First time posting, I think. HP is installed on a crate Chevy L31, Vortec heads, chunky cam, headers. This drivetrain was installed in a vehicle for 9k miles, then pulled, sat for around a year, and installed in a new vehicle. It's run well for ~ 1200 mi since that install. The behavior I'm now experiencing only happens after driving 30-40 min with lots of stop and go. I've noticed the electric fan needs to trigger on (205°F) and off (195°F) around 6 times for this issue to occur. What happens under these circumstances is:

    - 1st, the temp reading starts to fluctuate wildly resulting in the fan being triggered on/off rapidly. Readings start scrolling from 175°F-210°F.
    - After that's the case for a couple minutes the AFR starts to go way rich, with numbers in the mid single digits. This is fluctuating as well.
    - The intensity of the AFR fluctuating and resulting engine stumble goes from a hiccup to undriveable in about 60 seconds.
    - The LCD display loses connectivity with computer and will not respond to touch, displays error message.
    - Pulling over, shutting down, and waiting for 15 min seems to reset things.

    Driving for 30 min without the stop/go and multiple fan on/off cycles results in perfect manners and no issues.
    I have new Bosch WBO2 and Coolant Temp sensors in the mail. What else should I be looking at? Many thanks in advance.

  2. #2
    Join Date
    Nov 2014
    Location
    Ont. Canada
    Posts
    1,276

    Default

    Datalog the event.

  3. #3
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,817

    Default

    Originally Posted by Danny Cabral
    Quick Datalogger Information:
    Always provide data, not just symptoms. Is the AFR & ignition timing optimized? Overlay the datalog onto your Global File.
    Ensure the Target A/F Ratio table is properly programmed for your engine. Ensure the ECU is "Learning" (Learn Table LINK).
    Scroll through the datalog to the problem area. Then look exactly where this happens on the Base Fuel & Timing Tables. Scrutinize:
    RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery.

    Using the Holley EFI software (LINK), look at where the live cursor moves to during this occurrence, and
    manually tune that area of the Base Fuel Table (enrich or lean) & Base Timing Table (optimize ignition timing).


    I find the most helpful datalog function, is overlaying the datalog on your Global File.
    I'm in the habit of using the datalog Overlay feature every time I review a datalog.
    Click on "Datalog" (on the top Toolbar), "Activate Overlay", then "Open Data Log".
    You can literally "playback" a recorded event, and watch it as it happened on any screen.
    Minimize (shrink) the datalog window, and move it to the bottom of any Global File screen.
    Then click & scroll anywhere on the datalog, and watch it playback on your Global File (EFI software).
    http://documents.holley.com/techlibr...9r10543rev.pdf (Holley EFI Datalogger Instructions)
    https://forums.holley.com/showthread...s-amp-Datalogs (Datalog & System Log Information - Read "NOTES")
    https://www.youtube.com/watch?v=iqHO...C6FEA0BB99AF17 (How To Record & Email A Datalog)
    https://www.youtube.com/watch?v=q7OZUXLRS1Q (How To Record A System Log & Diagnose A No-Start Condition)
    https://forums.holley.com/showthread...7531#post77531 (Closed Loop Datalog Tuning - Posts #2, #4 & #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/2800 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.

  4. #4

    Default

    Will do. I'm borrowing a Windows laptop from a friend to do this, and I've never gone into the system beyond the quick start and setting idle speed and fan control, so I might be a little slow and ask a bunch of questions.

  5. #5
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,817

    Default

    Quote Originally Posted by Roger Benton View Post
    Driving for 30 min without the stop/go and multiple fan on/off cycles results in perfect manners and no issues.
    https://forums.holley.com/showthread...839#post211839 (Related Forum Thread)

    I have new Bosch WBO2 and Coolant Temp sensors in the mail.
    I agree with replacing these two sensors.
    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/2800 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.

  6. #6

    Default

    I actually suspect this is an ignition issue. Something is causing multiple misfires to occur, which is throwing off the wideband and also causing temperature swings. Double check the ignition system and all other wiring pertaining to the ECU and the ignition system. Also make sure you are using RFI suppressor core ignition wires.

    I'd load the last known good tune, clear the Learn Table, and disable Closed Loop. See what happens. After a 30-40 minute drive, something is getting hot. I suspect something in the ignition system is failing due to high heat. Andrew
    Last edited by andrewb70; 06-03-2019 at 06:28 PM.

  7. #7

    Default

    I suspect heat as the culprit as well. I think once the temp reading starts fluctuating it stops reading true temp and stops triggering the fan, allowing higher than normal temps. And that's when the AFR starts to go loopy, which as I understand it, is a result of the WBO2 sensor reading so what you're saying makes sense.

    I datalogged tonight's drive home from work, about 30-35 min. All was running fine till I got off the parkway and into my neighborhood and start/stop driving ensued. Once the fan cycled on the first time, the temp reading slowly started to go and then the AFR. It didn't get bad enough to stall out by the time I parked and ended the datalog. I'll Overlay this datalog as Danny describes above and see what I can see. Loading the last good tune is a good idea, I can do that now while I wait on a friends Windows laptop. Thanks.

  8. #8

    Default

    Quote Originally Posted by Danny Cabral View Post
    https://forums.holley.com/showthread...839#post211839 (Related Forum Thread) I agree with replacing these two sensors.
    Thanks for this and the info above. I haven't yet delved into the tuning with a laptop; something tells me I'm about to encounter a bit of a learning curve.

  9. #9

    Default

    If you want it to run perfectly, laptop tuning is the only way.
    IG @projectgattago

  10. #10
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,817

    Default

    Absolutely...and he realizes it.
    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/2800 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.

Page 1 of 2 12 LastLast

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