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Thread: 1st Start - High Idle Problem

  1. #1

    Default 1st Start - High Idle Problem

    Checked pre-start fuel pressure - set pressure regulator to 43 psi.
    Checked pre-start ignition timing - set distributor to 10° BTDC.
    Performed TPS AutoSet. Verified TPS goes from 0 to 100 with full pedal travel.

    Car would not start. Next attempt at starting I pumped the throttle. It would start, but I needed to keep the throttle partially down to get it to stay running. When I let off the throttle, the car would die. IAC varied from 20% to 80%. Whenever the car would idle up, the IAC was high. As the idle fell, IAC would go down. Not sure if the IAC was getting the RPM up, or reacting to the RPM. RPM was showing on both the laptop and handheld gauge.

    Next, I opened the throttle plates with the throttle screw. Performed TPS reset. Now, the car will start, but it idles at 3000 rpm. IAC is at 35%. Tried closing the throttle screw with reset TPS again, but same thing. If it goes under 2500 rpm, the motor stalls.

    Any thoughts? I will check for air leaks again, but have checked multiple times. I can not find the static timing option in the software, so I'm not sure where the timing is. I went to the base timing table while the car was running at 3000 rpm. I didn't see an "orange bubble" on the map.

    I'm not sure if what to check next. Not sure about fuel enrichment or other parameters.

    I'll keep searching unless someone has a great idea. Tom

  2. #2

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    OK, some improvement. I found the static idle setting. Setting this to 30, the car will start. It will hunt for the idle up and down (approx 700-1500 rpm), then die after a few seconds. The base timing I think I need to reset my base idle timing in the program to 16, instead of 10. My previous 351W needed 16-18 base timing to idle smoothly. This 408 may need the same. Gonna try that next.

    Edit: Maybe not. The Ignition Reference Angle is set at 10°, and that is what the distributor is set at. The base idle timing is set at 25°. I think this is close enough to 30° to not be the cause. I verified the Ignition Reference Angle before I started the car. It hasn't run long enough to check the timing with it running.
    Last edited by Texasdoc; 10-21-2014 at 06:38 PM.

  3. #3
    Join Date
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    Quote Originally Posted by Texasdoc View Post
    Next, I opened the throttle plates with the throttle screw. Performed TPS reset. Now, the car will start, but it idles at 3000 rpm. IAC is at 35%. Tried closing the throttle screw with reset TPS again, but same thing. If it goes under 2500rpm, the motor stalls.
    Adjust the idle speed screw on throttle body, to achieve an IAC Position of about 2% at hot idle.
    Remember to perform another TPS AutoSet, whenever you adjust the idle speed screw on the throttle body.
    In the Idle ICF, the "Target Idle Speed (RPM)" must be programmed to the desired RPM speed at hot idle.
    If the idle speed screw is unscrewed too far, the engine is inhaling air from an additional source - vacuum leak.
    http://forums.holley.com/showthread....neral-IAC-Info (IAC Information - Read "IAC NOTES")
    http://forums.holley.com/showthread....ents-Read-This! (Initial Checks & Adjustments - Read This!)

    I can not find the static timing option in the software, so I'm not sure where the timing is.
    The EFI software "Enable Static Timing Set" is in the "Sync With ECU" drop down menu - top Toolbar.

    You should initially synchronize the ignition timing by cranking the engine with the fuel injector harness disconnected.
    This should've already been accomplished, before you started the engine for the first time.
    http://documents.holley.com/techlibr...r10546rev1.pdf (Quick Start Guide - Page 5)
    http://forums.holley.com/showthread....ing-Holley-EFI (Ignition Timing Synchronization)

    FYI: If you're unsure about the initial distributor installation/positioning, or you'd like to verify the base timing before starting the engine, it's suggested to disconnect the fuel injector harness and crank the engine while viewing the Cranking Timing with a timing light. This prevents the engine from starting, but still allows you to adjust & confirm the base timing (engine safety). When the Cranking Timing is correct (synchronized), the timing at idle will be too.

    If you're cranking the engine (with the injector harness disconnected), sync at 15° or whatever your Cranking Timing is.
    If you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/2800 RPM converter, M4602G aluminum driveshaft, 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

    Quote Originally Posted by Danny Cabral View Post
    Adjust the idle speed screw on throttle body, to achieve an IAC Position of about 2% at hot idle.
    Remember to perform another TPS AutoSet, whenever you adjust the idle speed screw on the throttle body.
    In the Idle ICF, the "Target Idle Speed (RPM)" must be programmed to the desired RPM speed at hot idle.
    If the idle speed screw is unscrewed too far, the engine is inhaling air from an additional source - vacuum leak.
    http://forums.holley.com/showthread....neral-IAC-Info (IAC Information - Read "IAC NOTES")
    http://forums.holley.com/showthread....ents-Read-This! (Initial Checks & Adjustments - Read This!)
    I can't get it to run long enough for the car to get hot.

    Quote Originally Posted by Danny Cabral View Post
    The EFI software "Enable Static Timing Set" is in the "Sync With ECU" drop down menu - top Toolbar.
    Found that. See post #2.

    Quote Originally Posted by Danny Cabral View Post
    You should initially synchronize the ignition timing by cranking the engine with the fuel injector harness disconnected.
    This should've already been accomplished, before you started the engine for the first time.
    http://documents.holley.com/techlibr...r10546rev1.pdf (Quick Start Guide - Page 5)
    http://forums.holley.com/showthread....ing-Holley-EFI (Ignition Timing Synchronization)

    FYI: If you're unsure about the initial distributor installation/positioning, or you'd like to verify the base timing before starting the engine, it's suggested to disconnect the fuel injector harness and crank the engine while viewing the Cranking Timing with a timing light. This prevents the engine from starting, but still allows you to adjust & confirm the base timing (engine safety). When the Cranking Timing is correct (synchronized), the timing at idle will be too.

    If you're cranking the engine (with the injector harness disconnected), sync at 15° or whatever your Cranking Timing is.
    If you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
    See post #1 - I did this. I cranked the engine with the fuel pump powered off/ECU and ignition on. With a timing light, I set the distributor when plug #1 fired at 10° BTDC. The ignition reference angle is confirmed on the ECU at 10°.

    Right now, I don't have the fuel pressure regulator connected to manifold vacuum. Does this NEED to be connected? I do have the sensor plugged into the ECU harness, and the handheld & computer read the sensor's output as 43. Since I have the sensor, does the ECU correct for pressure changes automatically?

    On Base Calibration, how do I tell if it has a 2, 3 or 5 bar base calibration? The handheld never asked me. I haven't changed anything or loaded any new maps. The software states the MAP sensor type is "Holley 1 bar".
    Last edited by Texasdoc; 10-21-2014 at 07:02 PM.

  5. #5

    Default

    1st - thanks for trying to help Danny. I really appreciate it.


    Quote Originally Posted by Danny Cabral View Post
    Let's first cover the basics:
    1) Are the Engine Parameters, Ignition Parameters, Sensors, Idle & Spark ICFs correctly programmed?
    http://documents.holley.com/techlibr...librations.pdf (Base Calibrations)
    http://documents.holley.com/techlibr...r10546rev1.pdf (Quick Start Guide)
    Remember, the base calibration you start with, must correspond to the MAP sensor you're using:
    For example, you can't use a naturally aspirated base calibration for a forced induction engine.
    This is because the 2,3,5 bar MAP sensor selection only changes the kPa load Y-axis, but not the Base Fuel Table lb/hr
    values (creating an excessively lean map) or the Base Timing Table degree values (excessively advanced timing map).
    You must choose a 2,3,5 bar base calibration or reconfigure your existing Global Folder's Fuel & Timing Tables accordingly.
    I just used what the handheld programmed the ECU with. It never asked. I assume it used naturally aspirated, what came in the Terminator kit. How do I check if it used the right fuel map? Should I just start over with the files on the computer to make sure? The quick start guide says "If you are fine tuning a Terminator unit, we suggest retrieving the Global Folder from the ECU after loading it from the handheld." It appears the files on the computer aren't for a TFI setup. I don't know if I can select TFI unless I use the handheld wizard. This is what I did.

    Quote Originally Posted by Danny Cabral View Post
    2) Has the fuel pressure been properly adjusted and "Actual System Pressure" (Terminator - "Fuel Pres") accurately entered in Engine Parameters?
    With TBI, the Actual System Pressure is measured anytime engine is running (no vacuum reference hose), or key-on/engine-off pump running.
    With MPFI, the Actual System Pressure is measured with the vacuum reference hose temporarily disconnected, or key-on/engine-off pump running.
    I did this with key on, engine off, pump running. Computer and handheld shows 43.

    Quote Originally Posted by Danny Cabral View Post
    3) Has the idle speed screw on throttle body, been adjusted to achieve an IAC Position of about 2% at hot idle?
    Remember to perform another TPS AutoSet, whenever you adjust the idle speed screw on the throttle body.
    In the Idle ICF, the "Target Idle Speed (RPM)" must be programmed to the desired RPM speed at hot idle.
    http://forums.holley.com/showthread....neral-IAC-Info (General IAC Information)
    Can't get it to a "hot" state. I guess I can make small changes with the throttle screw until I can get it to run until hot, then adjust (while running?) for IAC of 2%.

    Quote Originally Posted by Danny Cabral View Post
    4) Are the crank & cam sync sensor signals timed correctly?
    http://forums.holley.com/showthread....m-Sensor-Setup (Crank & Cam Sensor Setup - Not for LSx or TBI)

    5) Has the ignition timing been synchronized with the ECU?
    http://forums.holley.com/showthread....ing-Holley-EFI (Timing Synchronization - Not for LSx)
    Yes, see previous.
    Last edited by Texasdoc; 10-21-2014 at 07:19 PM.

  6. #6

    Default

    Just a thought...
    I checked pre-start timing with the fuel pump disabled. I set the distributor at 10°, which is my Ignition Reference Angle.
    However, I think the crank setting is 15°. If my timing is 5° retarded, that would make the idle run rough?

    Unfortunately, I ran out of daylight today. Since I can get it to run at 2500 rpm, I will set the static timing at 30°,
    then set the distributor at 30°, then clear the static timing, and see if the idle timing matches. Hopefully...

  7. #7
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    Quote Originally Posted by Texasdoc View Post
    I cranked the engine with the fuel pump powered off/ECU and ignition on. With a timing light, I set the distributor when plug #1 fired at 10° BTDC. The ignition reference angle is confirmed on the ECU at 10°.
    The Ignition Reference Angle is not the idle timing.

    Right now, I don't have the fuel pressure regulator connected to manifold vacuum. Does this NEED to be connected?
    Yes: http://forums.holley.com/showthread....0801#post50801 (Additional Information)

    I do have the sensor plugged into the ECU harness, and the handheld & computer read the sensor's output as 43. Since I have the sensor, does the ECU correct for pressure changes automatically?
    The fuel & oil pressure transducers are completely optional. The engine runs the same with or without them.
    The fuel & oil pressure transducers are used for Data Monitoring, Data Logging and setup Outputs based on fuel & oil pressure.

    This is not to be confused with the "Actual System Pressure" fuel parameter (in Engine Parameters),
    which must be entered accurately because the ECU does use this single value for lb/hr calculations.
    With TBI, the Actual System Pressure is measured anytime engine is running (no vacuum reference hose), or key-on/engine-off pump running.
    With MPFI, the Actual System Pressure is measured with the vacuum reference hose temporarily disconnected, or key-on/engine-off pump running.

    On Base Calibration, how do I tell if it has a 2, 3 or 5 bar base calibration? The handheld never asked me. I haven't changed anything or loaded any new maps. The software states the MAP sensor type is "Holley 1 bar".
    If you haven't changed the MAP sensor, it's still set to "Holley 1 bar".
    The Terminator EFI is intended for naturally aspirated engines by default.

    I just used what the handheld programmed the ECU with. It never asked. I assume it used naturally aspirated, what came in the Terminator kit. How do I check if it used the right fuel map?
    When using the Calibration Wizard, you were asked about the EFI system, engine size & camshaft type.
    https://www.holley.com/document/199r10653rev3.pdf (Terminator Manual - Section 20, Page 22)

    It appears the files on the computer aren't for a TFI setup. I don't know if I can select TFI unless I use the handheld wizard. This is what I did.
    "Ford TFI" (8 Cylinder - SEFI) is an Ignition System option on the handheld controller (Setup Wizard) and laptop (EFI software).
    https://www.holley.com/document/199r10653rev3.pdf (Terminator Manual - Figure 39, Page 22 & 23)

    Can't get it to a "hot" state. I guess I can make small changes with the throttle screw until I can get it to run until hot, then adjust (while running?) for IAC of 2%.
    Sometimes it's easier to temporarily block off the IAC air inlet port (with a piece of tape), until the engine is idling good (tuned).

    Just a thought...
    I checked pre-start timing with the fuel pump disabled. I set the distributor at 10°, which is my Ignition Reference Angle.
    However, I think the crank setting is 15°. If my timing is 5° retarded, that would make the idle run rough?
    Yes, unsynchronized timing (especially retarded) can definitely cause a rough idle.

    Again, you should initially synchronize the ignition timing by cranking the engine with the fuel injector harness disconnected.
    This should've already been accomplished, before you started the engine for the first time.
    https://www.holley.com/document/tech...r10546rev1.pdf (Quick Start Guide - Page 5)
    http://forums.holley.com/showthread....ing-Holley-EFI (Ignition Timing Synchronization)

    If you're cranking the engine (with the injector harness/fuel pump disconnected), sync at 15° or whatever your Cranking Timing is.
    If you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/2800 RPM converter, M4602G aluminum driveshaft, 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

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    Quote Originally Posted by Danny Cabral View Post
    The Ignition Reference Angle is not the idle timing.
    This is not very well explained in the manual. I found it in the Quick Start guide on page 6 just now. For some reason, I was thinking to set it at 10°, rather than the crank timing setting. Not sure where I got that.

    Quote Originally Posted by Danny Cabral View Post
    OK, recommended, but optional. I'll hook it up.

    Quote Originally Posted by Danny Cabral View Post
    This is not to be confused with the "Actual System Pressure" fuel parameter (in Engine Parameters),
    which must be entered accurately because the ECU does use this single value for lb/hr calculations.
    With TBI, the Actual System Pressure is measured anytime engine is running (no vacuum reference hose), or key-on/engine-off pump running.
    I did this. Verified.

    Quote Originally Posted by Danny Cabral View Post
    Sometimes it's easier to temporarily block off the IAC air inlet port (with a piece of tape), until the engine is idling good (tuned).
    Will try that.

    Quote Originally Posted by Danny Cabral View Post
    This should've already been accomplished, before you started the engine for the first time.
    If you're cranking the engine (with the injector harness/fuel pump disconnected), sync at 15° or whatever your Cranking Timing is.
    If you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
    I did this, but got it wrong. Somewhere I got 10°, instead of the Crank Timing setting. I think I was following a startup procedure explained on one of the threads of this forum. I will go reset the distributor to 15°, check the static idle, and then mess with the throttle blades. Will get to it tonight after work.

    Thanks again!

  9. #9

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    OK, idling much better now. Down to 950. Reset the timing - I was off; using 10° instead of 15°. Now the timing follows the timing table. To get a lower idle, I had to plug the IAC port with tape, decrease the idle screw, and wait for the ECU to learn the new/lower idle. After about two minutes at each point, the idle would stabilize. Then I would back out the screw some more, do a TPS reset, then wait for it to Learn again. Repeated this procedure 4-5 times to get the idle to 950. The removed the IAC tape, did a TPS reset, then adjusted for IAC of 2%. Then did a TPS reset again. Idles smooth.

    A quick question. I verified the fuel pressure with engine on, vacuum reference unplugged to be 43 psi. I got the car to idle with the above procedure with this. Now that I have plugged in the vacuum reference, I just ignore the fuel pressure?

  10. #10
    Join Date
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    Connecticut
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    Quote Originally Posted by Texasdoc View Post
    A quick question. I verified the fuel pressure with engine on, vacuum reference unplugged to be 43 psi. I got the car to idle with the above procedure with this. Now that I have plugged in the vacuum reference, I just ignore the fuel pressure?
    Basically, yes. The vacuum reference (hose) will vary the fuel pressure.
    https://www.vaporworx.com/documentat...re-regulators/ (Vacuum Referenced Fuel Pressure Regulators)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/2800 RPM converter, M4602G aluminum driveshaft, 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.

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