F4I Motor issues

[chuckBYU]

BYU has just started a FSAE team and we just got our first f4i motor. We are trying to get it started but i can't get the ECU to fire the plugs or the injectors (we are trying to get it going stock before we do anything to it). We have the original wiring harness. i would like to remove some of it so it is not so ugly but i'm not sure what is necesarry for the engine and what isn't. I must be missing something simple because i've been through the wiring diagrams and I think i have it hooked up right. Any help would be greatly appreciated.

BYU FSAE Engine Team

[psychobilly]

The first place I would look is your crank position sensor.

[GTmule]

We found (f3) this year that the best way to start is by completely pitching the honda starting circuit, and using a ford (or whatever) starter relay. It eleminates all the little variables liek neutral safety switches, kickstand sensors, etc, etc, plus it's an easy to get, failsafe, and cheap part. Not really applicable to your current problem, but it definately tidies things up, and simplifies your wiring.

[Wizard]

The key switch is super important. The ecu needs the voltage signal from the key switch for engine to start.

There has been several discussions on this forum about eliminating the key switch and other items from the stock harness.

[chuckBYU]

Do you know where to find the posts about eliminating the key switch and other items. This is what i need. I need to know what is absolutly necessary to get the motor going and eliminate everything else (the wiring is a mess right now). I'm just not sure which signals the ecu needs to run. Thanks for all your help so far.

[OmniscientGT]

When we use the stock f4i harness, we eliminate all of the safety switches (Kickstand switch etc.). These can be taken out of the loop with a simple wire jumper out of the ecu. While I'm sure you can find a work around for the switch and its 12v supply issue, its cute to put that big ass switch somewhere on the car. The point, I take it, is to have a running car. Use the stock key switch and get yourself running. Then take the time to wire the switch out of the picture. While the ideal may be what we strive for, it often leads to us beating our heads against the wall.

Cheers

[chuckBYU]

We finally got it running. Thanks for all your help. I started another thread about ECU's so please read it and put your $.02 in. Thanks.

[lucass]

We had a difficult time to try to get our engine running with the stock ECM. We got it to work so I quickly drew it up. It may not be 100% but it help alot. It is on my webspace at:

http://www.ece.ualberta.ca/~lucas/Stock (http://www.ece.ualberta.ca/%7Elucas/Stock) F4i Wiring.mdi

Hope this helps