Test Won't Complete

Discussion in 'Fox 5.0 Mustang Tech' started by Disgruntled3lf, Dec 12, 2013.

  1. So I started a thread here:

    General advice was that I should get a tester and pull the codes. Tester came in today and I performed the koeo test. It gave me codes 31, 81, and 82. It froze here for about 5 minutes and never put out the separator code or the cmm codes. In addition when I performed the koer test it did nothing until the tester eventually turned off. My mods are listed as they were told to me in the picture.

    Attached Files:

  2. Go back to your original post and see my instructions for dumping the codes. Use that method instead of the code reader and see what sort of results you get.
  3. With the engine running, plug the code reader in, and then hit the test button. You should see the square start blinking and the car should start spurting off codes

    Code 31 is EGR code. What's the condition of your EGR? Is it functional? Or has it been deleted?

    Code 81 and 82 are common codes that result from removal of the smog pump and related hoses on the passenger side of car. Doesn't affect how engine runs. These two codes can be ignored.
    #3 Mustang5L5, Dec 13, 2013
    Last edited: Dec 13, 2013
  4. So this is the first day I've had time to get under the hood and look. Seems that the egr has been removed but not deleted since the computer is crying about it. Also a picture of the maf.

    Attached Files:

  5. Also I used the code reader correctly. It worked for those codes then stopped. Don't know why.
  6. Why not try KOEO & see if completes the code test?
  7. I did.
  8. I have the Innova 3145, if that's the one you got. Never heard of one freezing & not completing the test.

    You said in the other thread: "...So my car has had some issues since I got it. After sitting for a few hours I have to give it gas for a few minutes to keep it running otherwise the RPM's will drop <700 and it will die..."

    Mine does the same (30lb, supercharger, correct MAF) & I have no bad codes at all. If the code reader won't read codes, it's likely the EEC has a problem, especially since it once had a chip). Can you get the Part Number off the EEC? Here's what to look for: http://oldfuelinjection.com/?p=17

    I can't tell what's unplugged, it's too close up. If it was zoomed out, might be able to tell you. Probably something in the thermactor air system. The air pump used to be in that area.
    #8 Blown88GT, Dec 14, 2013
    Last edited: Dec 14, 2013

  9. The computer crying about it isn't necessarily a bad thing. As long as the code is generated, the EEC turns off the EGR function.

    When you start trying to fool it with resistors and such, things can get messy. Unless you can custom tune and remove the function, let the EEC see it's missing.

  10. Pretty sure that's the plug that leads to the charcoal canister. Looks like that's been removed as well.

    That black circular plug looks like it's on the fuel rail?
  11. So test now completes. KOER code 12 13 19. And I pulled off my maf housing. It looks like I have one with a removable sampling tube. How can i tell if what i have is for19 or 30lb injectors?

    Attached Files:

  12. So it's stock electronics in an aftermarket housing. Good chance it's calibrated correctly.

    LEts focus on the codes. Code 12 and 13 are idle air controller codes. I'm going to assume whoever installed it didn't do the idle reset procedure correctly. If you unplug the IAC, and the car stalls while running, then it's a good chance it wasn't setup right.

    On the throttle body there is an idle set screw. You never touch this screw, except for right now. Open the throttle body up a few turns by screwing this screw in. Unplug the IAC. You want the screw to be in far enough that the engine runs with the IAC unplugged. Now slowly back the screw down. You are trying to set your minimum idle point here. You want the engine to have a healthy, but low idle here - as low as you can go without the engine struggling to run.

    Turn off engine, disconnect battery to reset the computer for 30 mins. Hook it back up, plug the IAC back in, and start the engine. It should idle fine. Give it a few cycles to relearn idle strategy, and then rerun the codes to see if 12 and 13 are gone.

    Code 19 (engine running) - Erratic idle during test (reset throttle & retest) - Idle Set Procedures

    basically confirms you have an idle issue. Try the reset procedure, put some miles on the car and rerun the codes again
  13. Tried what you suggested. If the screw shown in the picture below (away from intake) of the tps is the one i was supposed to turn it did nothing. No change in idle if it was all the way down or all the way up. The idle did speed up wheni removed the bolt and air started escaping. Shouldn't air have been pulled in? Could this be related to the charger? And as far as getting a tune I don't know where to do that. I live in Cookeville tn if anyone has a suggestion. Also I noticed the idle will fluctuate from 750 to 1100 rpms. And if I Rev the motor it will idle at around 1300 to 1400 for several seconds before going back down. I'm at a loss here and none of the mechanics I've talked to know about chargers and mods.

    Attached Files:

  14. Also, unplugging the iac made no difference other than immediately following removal or reconnection. And yes the unplugged black circular thing is on the fuel rail.
  15. This suggests that the idles speed has been set by turning the throttle blade stop screw.

    The following fixes are from the "Surging Idle Checklist , which is entirely devoted to fixing idle problems. It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 134,000 hits, which indicates it does help fix idle problems quickly and inexpensively.

    IAC doesn't work: look for +12 volts at the IAC red wire. Then check for continuity between the white/lt blue wire and pin 21 on the computer. The IAC connector contacts will sometimes corrode and make the IAC not work. The red wire on the IAC is always hot with the engine in run mode. The computer provides a ground for the current for the IAC. It switches the ground on and off, making a square wave with a varying duty cycle. A normal square wave would be on for 50% of the time and off for 50% of the time. When the idle speed is low, the duty cycle increases more than 50% to open the IAC more. When the engine speed is high, it decreases the duty cycle to less than 50% to close the IAC. An old-fashioned dwell meter can be used to check the change: I haven’t tried it personally, but it should work. In theory, it should read ½ scale of whatever range you set it on with a 50% duty cycle. An Oscilloscope is even better if you can find someone who has one and will help.


    Recommended procedure for cleaning the IAC/IAB:
    Conventional cleaning methods like throttle body cleaner aren’t very effective. The best method is a soak type cleaner used for carburetors. If you are into fixing motorcycles, jet skis, snowmobiles or anything else with a small carburetor, you probably have used the one gallon soak cleaners like Gunk or Berryman. One of the two should be available at your local auto parts store for $22-$29. Take the solenoid off the body and set it aside: the carb cleaner will damage some types of plastic parts. Soak the metal body in the carb cleaner overnight. There is a basket to set the parts in while they are soaking. When you finish soaking overnight, twist the stem of the IAB/IAC that sticks out while the blocker valve is seated. This removes any leftover deposits from the blocker valve seat. Rinse the part off with water and blow it dry with compressed air. The IAC/IAB should seal up nicely now. Once it has dried, try blowing through the bottom hole and it should block the air flow. Reassemble and reinstall to check it out.

    Gunk Dip type carb & parts soaker:

    Setting the base idle speed:
    First of all, the idle needs to be adjusted to where the speed is at or below 600 RPM with the IAC disconnected. If you have a wild cam, you may have to raise this figure 100-150 RPM or so. Then the electrical signal through the IAC can vary the airflow through it under computer control. Remember that the IAC can only add air to increase the base idle speed set by the mechanical adjustment. The 600 RPM base idle speed is what you have after the mechanical adjustment. The IAC increases that speed by supplying more air under computer control to raise the RPM’s to 650-725 RPM’s. This figure will increase if you have a wild cam, and may end up between 800-950 RPM

    Remember that changing the mechanical idle speed adjustment changes the TPS setting too.

    This isn't the method Ford uses, but it does work. Do not attempt to set the idle speed until you have fixed all the codes and are sure that there are no vacuum leaks.

    Disconnect the battery negative terminal and turn the headlights on. Leave the battery negative terminal disconnected for 5 minutes or so. Then turn the headlights off and reconnect the battery. This erases the computer settings that may affect idle performance.

    Warm the engine up to operating temperature, place the transmission in neutral, and set the parking brake. Turn off lights, A/C, all unnecessary electrical loads. Disconnect the IAC electrical connector. Remove the SPOUT plug. This will lock the ignition timing so that the computer won't change the spark advance, which changes the idle speed. Note the engine RPM: use the mechanical adjustment screw under the throttle body to raise or lower the RPM until you get the 600 RPM mark +/- 25 RPM. A wild cam may make it necessary to increase the 600 RPM figure to 700 RPM or possibly a little more to get a stable idle speed.
    Changing the mechanical adjustment changes the TPS, so you will need to set it.

    When you are satisfied with the results, turn off the engine, and re-install the SPOUT and reconnect the IAC. The engine should idle with the range of 650-750 RPM without the A/C on or extra electrical loads. A wild cam may make this figure somewhat higher.

  16. That's not the correct screw. That's just a vacuum port. Make sure that's sealed tight.

    I'll try and find a pic, but the idle set screw is on the underside of the throttle body. The linkage the throttle cable is connected to hits this screw.

    If unplugging the IAC did nothing, then that means the screw needs to be backed down a bit.
  17. Your setup won't look like this, but here's the basic throttle set screw


    Look under the throttle body, the screw should be accessible from the front. Unplug the iac and back this out and the idle should drop.
  18. So I tried what Mustang5l5 suggested I opened the throttle body up and starteded the car. Then every turn of the screw back caused the engine to stutter. I finally founda balance at 1500rpm which seems super high to me. And by the time i finished my headers were glowing. No exaggeration or figure of speech.
  19. It won't let me edit but I do know how to spell started.
  20. That sounds like a lean issue.

    Really getting hard to diagnose without seeing or knowing what parts are on the car. It's possible it's a fuel issue, but that's a guess because need to really know what the MAF is calibrated for.

    Was there a point where the car ran well for you? OR has it always been like this