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Thread: Coyote starting issues

  1. #1
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    Question Coyote starting issues

    I have a mk4 with a gen 2 coyote motor. I followed EdwardB wiring and the fuel pump is only turning on in the start position. The car will turn over for a second and then turn off. I was wondering if anyone has run into this issue before. On my ignition switch, I only have the blue wire connected to the start terminal. I have been looking over my wiring and tried to see if I wired the ignition switch incorrectly but I can’t find why the fuel pump not working when in the run position. Any help would be great!
    Last edited by toddhack; 08-10-2018 at 06:23 PM.

  2. #2
    Senior Member edwardb's Avatar
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    I'm a little unsure of exactly what you're describing. Let's cover the basics. In addition to power and a functioning fuel pump, the Coyote only needs two wires from the RF harness and your ignition switch.

    (1) Coyote pigtail lead #5 (light green) Ignition Relay Trigger needs +12V any time the ignition key is in the run or start position. Normal practice is to use the RF harness Orange EFI/Coil wire. This voltage "wakes up" the PCM and is the signal for the Coyote system to run the fuel pump and allow the engine to start and run. Put a VOM on this connection and make sure there's +12V at all times when in run or start.

    (2) Coyote pigtail lead #3 (light blue) Starter Motor Request (SMR) needs +12V when the ignition key is turned to the start position. Again, recommend putting a VOM on the connection and make sure there's +12V when in start. You mention you have the "blue wire" connected at the start terminal. In the RF harness, there are two blue wires at the start terminal. One goes to the RF harness Blue EFI Crank Power wire. This is the one I recommend using. The other blue wire goes to the RF clutch safety and then to the starter solenoid. Since the Coyote has it's own clutch safety switch and starter solenoid wires (which I assume you're using) this wire can be removed or capped.

    When you turn the ignition key from the off to run position (first position) the fuel pump should start but will run only a couple seconds before switching off. It waits for the start command for the pump to run again. This is normal Gen 2 behavior, and different than the Gen 1 which runs continuously at all times. If this isn't happening (e.g. you don't hear the pump start and then turn off) either (1) the fuel pump isn't wired properly, or (2) the Ignition Relay Trigger wire (#1 point above) isn't getting +12V so the PCM is not commanding the fuel pump to run.

    When you say it will "turn over for a second and then turn off" do you mean it just stops cranking? Or the engine starts and then shuts off? Assuming everything I've described up to now is correct (Ignition Relay Trigger, Starter Motor Request, fuel pump running as I described) then something else is wrong obviously. The fact that you say it turns off (again not sure what that means) could mean a sensor isn't connected or has failed and the PCM shuts down the process. It won't start if the MAF sensor isn't connected or is backwards, for example. But just guessing at this point without more feedback.
    Last edited by edwardb; 08-10-2018 at 08:32 PM.
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  3. #3
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    This is great, thanks so much. I’ll walk through this in the morning..... One quick question related to orange EFI/Coil wire. What terminal on the ignition switch should I attach this to? The ignition terminal or to the bat lead.

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    Senior Member edwardb's Avatar
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    Quote Originally Posted by toddhack View Post
    This is great, thanks so much. I’ll walk through this in the morning..... One quick question related to orange EFI/Coil wire. What terminal on the ignition switch should I attach this to? The ignition terminal or to the bat lead.
    The ignition switch isn't affected by the Coyote installation. It's wired exactly like the RF instructions shows. The RF harness orange EFI/Coil wire goes to the Coyote Pigtail that's part of the Coyote harness. Tells me you may not understand exactly how this is all working. Which I mean in the most positive way possible. Please read the first post again and follow it exactly. It's all logical once you see what's happening. But maybe not before then.
    Last edited by edwardb; 08-10-2018 at 09:54 PM.
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  5. #5
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    *** - adding my respone

    *****Paul – I really appreciate your help and I’m getting my head wrapped around this wiring slowly but the car still won’t start.
    Just to level set – yesterday I charged the battery 100% and had it tested and it’s good. Took off all ground wires and recleaned all the area’s and I feel these are all good.
    Two, I confirmed I wired the ignition switch correctly and understand the differences between the two oranges wire which I didn’t understand at first…

    I'm a little unsure of exactly what you're describing. Let's cover the basics. In addition to power and a functioning fuel pump, the Coyote only needs two wires from the RF harness and your ignition switch.

    (1) Coyote pigtail lead #5 (light green) Ignition Relay Trigger needs +12V any time the ignition key is in the run or start position. Normal practice is to use the RF harness Orange EFI/Coil wire. This voltage "wakes up" the PCM and is the signal for the Coyote system to run the fuel pump and allow the engine to start and run. Put a VOM on this connection and make sure there's +12V at all times when in run or start.

    ******(1) I have #1 working properly. +12V at both the run and start functions and wired to the RF orange EFI/Coil wire.

    (2) Coyote pigtail lead #3 (light blue) Starter Motor Request (SMR) needs +12V when the ignition key is turned to the start position. Again, recommend putting a VOM on the connection and make sure there's +12V when in start. You mention you have the "blue wire" connected at the start terminal. In the RF harness, there are two blue wires at the start terminal. One goes to the RF harness Blue EFI Crank Power wire. This is the one I recommend using. The other blue wire goes to the RF clutch safety and then to the starter solenoid. Since the Coyote has it's own clutch safety switch and starter solenoid wires (which I assume you're using) this wire can be removed or capped.

    *****(2) I walked through this and we are getting +12V on the “start position”. I used the RF Blue EFI crank wire and deleted the other blue wires for the RF safety switch/Solenoid since I am using the Coyote switches to handle this. So #2 is working properly.

    When you turn the ignition key from the off to run position (first position) the fuel pump should start but will run only a couple seconds before switching off. It waits for the start command for the pump to run again. This is normal Gen 2 behavior, and different than the Gen 1 which runs continuously at all times. If this isn't happening (e.g. you don't hear the pump start and then turn off) either (1) the fuel pump isn't wired properly, or (2) the Ignition Relay Trigger wire (#1 point above) isn't getting +12V so the PCM is not commanding the fuel pump to run.

    *****This is my problem….I was not getting any power from the dark green wire (connected to the tan wire). After checking the fuse in the Coyote box and trying to test to relay I went down to O’Reilly’s and picked up a new relay and a new PAL 40 amp fuse. After I installed these it worked but not properly. I had 2.2 volts on the run and then +12V on the start. I had the same results at the wire up in the footbox (green/tan fuel pump wire connection) and then the same readings at the fuel pump. 2.2V on run and +12V on start….is the correct? I expected to see +12V on both run and start…
    Then after trying this for a while then the fuel pump stopped running and I got 0 volts at both run and start from the green coyote wire and obviously at the pump. I must have wired something wrong and maybe its related to the inertia switch or???

    When you say it will "turn over for a second and then turn off" do you mean it just stops cranking? Or the engine starts and then shuts off? Assuming everything I've described up to now is correct (Ignition Relay Trigger, Starter Motor Request, fuel pump running as I described) then something else is wrong obviously. The fact that you say it turns off (again not sure what that means) could mean a sensor isn't connected or has failed and the PCM shuts down the process. It won't start if the MAF sensor isn't connected or is backwards, for example. But just guessing at this point without more feedback.

    ****I'm trying to post the video of the car starting on Friday but I can't seem to do it. I can send this to you separately. Now I can’t even get the starter to activate now. Any help is greatly appreciated.

    Thanks!

    Todd

  6. #6
    Senior Member Paul2STL's Avatar
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    Have you checked your mass air sensor? Mine the exact same thing as you first described. It would start then die within a second or two. I had the mass censor in wrong. I followed Paul's wiring exactly and have had no problems except as described oh and the inertia switch got me twice. I pushed the switch on accident when cleaning things up twice.
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    Thanks for the response. Yes We did double check the mass air flow sensor and it is correct per the FFR directions. I read this suggestion in an earlier post (likely yours!!). I’m concerned about the inertia switch. It’s fully depressed and when I check continuity across the terminals inside the switch it shows we have continuity so I think it’s working correctly but I’m not sure. I just went out to the garage and recheck everything and the issue remains is not having any power at the dark green coyote wire at run or start positions which powers the fuel pump. Any help is greatly appreciated.

  8. #8
    Senior Member edwardb's Avatar
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    Kind of a lot going on here. First, are you disconnecting the wires when you're taking the voltage measurements? Otherwise I'm not sure how reliable the results are. The RF harness Orange EFI/Coil wire and Blue EFI Crank Power wire should both be tested without the Coyote pigtail wires attached. You need to make sure you're only measuring voltage from the RF panel, not whatever voltage might be coming from the Coyote system. Assuming those still test OK, wire them back to the Coyote pigtail and they shouldn't need to be bothered again. Then test the Coyote pigtail lead #1 (green) fuel pump relay out. If you have the fuel pump fuse in the RF panel removed, it should be OK to test while still connected to the RF tan fuel pump wire since no other voltage would be available. It should show +12V briefly when the key it turned to the run (first) position. Maybe 1-2 seconds, so you need to be ready. It doesn't turn to a solid +12V until the engine is running and the PCM commands it to run full time.

    Another thing to check is the clutch bottom switch from the Coyote harness. I assume it's installed, plugged in, and properly being pushed down you push the clutch down. You are pushing the clutch down, right? Everything can be right, but the engine won't crank if that switch isn't closed.

    Assuming the above is OK, the fact that your starter motor still isn't cranking is concerning. Even if your fuel pump isn't wired correctly, or the inertia switch isn't working correctly, the Coyote PCM is still going to put +12V on the green fuel pump relay wire and try to start the engine. It has no way to know the fuel pump isn't running. Of course it's not going to start without fuel pressure. But it should at least crank. Same for the MAF sensor. Even if an issue there, it should still crank.

    I'm starting to run out of ideas. Check the above and we'll go from there. I'd also suggest, just for grins, checking for codes via the ODB2 port. Hoping you have an ODB2 scanner? If you don't, you should get one. Pretty much required with these engines to read and clear codes somewhere along the line. Basic models are relatively inexpensive and available at any parts store.
    Last edited by edwardb; 08-12-2018 at 07:47 PM.
    Build 1: Mk3 Roadster #5125. Sold 11/08/2014. Build 2: Mk4 Roadster #7750. Sold 04/10/2017. Build Thread
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