Coyt dies soon as it starts. Any ideas? All fuses are good. F1 fuse doesn't have power now it did yesterday. The engine hasn't stayed running yet. Today was the first fire up. Exciting but a bummer.
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Coyt dies soon as it starts. Any ideas? All fuses are good. F1 fuse doesn't have power now it did yesterday. The engine hasn't stayed running yet. Today was the first fire up. Exciting but a bummer.
Fuel pressure? Is the control pack controlling the pump or the RF wiring harness?
Mike
How's your MAF sensor? Hooked up? Oriented in the proper direction? No way to say with any certainty, but if you're getting the initial pump run when the key is turned on (like I described in my last post) I'm guessing the pump may not be the problem. What you're describing is what happens with either no or backwards MAF. The computer shuts the engine (and the pump) down almost immediately after starting if it's not getting the proper MAF signal. It can be installed backwards. The open end of the sensor (the part that is in the airflow) must be pointed toward the air cleaner.
Last edited by edwardb; 09-12-2019 at 06:06 PM.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014. Build 2: Mk4 Roadster #7750. Sold 04/10/2017. Build Thread
Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020. Build Thread and Video. Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020. Build Thread and Video
Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023. Build Thread. Sold 11/9/2023.
Mike,
Fuel pump is controlled by Ford pack. Also, tried it running direct to the battery for perfect 55 psi
Edward,
I will check MAF, that might be it. Also, going to put my scanner to it to see if I get rpms showing, to make sure crankshaft sensor is working
Edward,
You are the Man. The MAF sensor was backwards!!! starts and runs, first run. I was not hearing the few second power to the fuel pump when the key first turned on. So... still had to hot wire the fuel pump. It is being controlled by Ford distribution box. It is perfect if I hot wire the fuel pump. However, running through the distribution box, it is not giving signal. The Coyt ran great this morning and fired right up when I changed the flow of the MAF. I cut the Ron Frances wire pretty short, I guess I could move the wire back to the RF if I can get enough to solder the wire back on the stubby on the fuse box. Any ideas on the fuel pump through the distribution box?
Also, Thank you. I spent all day yesterday emailing and on the phone with Ford Performance and they never figured it out, you did in a few seconds!!!!
Zach
Glad that worked. Not an uncommon assembly error and I know from experience the engine starts and dies immediately like you described when there's no MAF signal. I guess I'm a little surprised Ford Performance didn't suggest that up front. For your fuel pump, let's back up a second. The Coyote harness/PDB has a dedicated circuit with a fuse and relay to run the fuel pump. Starting with the Gen 2, it has a momentary +12 volt run when the key is first turned on to pressurize the system, and will re-energize and keep running once the engine starts. If the PCM commands the engine to stop, either due to an error or you turn the key off, the pump is shut down. All what I've described before. The RF harness also has a fuel pump circuit with wiring back to the pump plus an inertia switch. Since the Coyote harness has neither an inertia switch or long enough wire to reach the pump, the solution has been to combine the two. There have been two approaches to this.
1. Break into the RF fuel pump circuit and replace the power feed from the RF panel with the power feed from the Coyote PDB. This makes the PCM controlled Coyote PDB the single source of power (including fuse and relay) and still utilizes the RF inertia switch and wiring to the pump. This is how I've wired both of my Coyote builds and it works perfectly. This older picture from the FF Coyote instructions shows which wire to tap. Using this wire, the RF panel no longer provides any power and the fuel pump fuse can be removed. The RF relay gets its power from the Coyote feed, and the inertia switch works as its supposed to. If the inertia switch is open, the relay ground connection is broken, relay opens, fuel pump goes off.
2. In later Coyote installation versions, FF showed breaking into the relay jumper wire rather than the main power wire. This works, but now there are two fuses in the circuit (Coyote PDB plus RF) and the RF panel now provides the power for the pump. I'm not sure of the reason for this difference. I prefer and use option #1.
Hope this helps. Decide which one you choose to use and wire accordingly. Also make sure the inertia switch is properly oriented and mounted, and that the button is pushed in. It should work. Good luck.
Last edited by edwardb; 09-13-2019 at 09:02 AM.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014. Build 2: Mk4 Roadster #7750. Sold 04/10/2017. Build Thread
Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020. Build Thread and Video. Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020. Build Thread and Video
Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023. Build Thread. Sold 11/9/2023.
Edward, thanks for the help and advice.
I did the second version because it was in my manual. I will look and compare and try to change to your picture. Thanks