New guy here, had some question I need help with

Nem0

New Member
Sep 3, 2018
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Houston tx
I have an 03 Mach 1 (FYI this might be a long read for some but I just wanted to include all the details, there were some small details I left out but will add them to the thread if anyone has information to help) so I just had the motor rebuilt, she slipped a rod bearing early this year so I decide to start modding a little early since it was stock when I got it, como cam stage 2, BBK long tubes and x pipe, ported heads, new clutch and flywheel and dyno tune, got the car out 3 weeks ago from the shop, runs great and everything but then the car starts to die out, turns out it was the alternator and the next day while leaving a friends house I back up out of his drive way and I hear a cranking sound, my starter was still kicking even after the car was started, turn the car off and it’s still kicking trying to turn the car on so I turn the ignition back on the it stops, next day car won’t start, turn the key and nothing, I can hear the fuel pump and fan on but no power to start, last weekend me and some friends switch out the starter and alternator but still nothing, side not: when I got the car back from the shop they told me they switched my ac control module because my ac wasn’t blowing cold at all, my module had a B on it the one they put had an R on it and just the other day my friends dad told me they were both burnt so idk if that may be apart of the problem, I know it’s a part of the fuel pump system I believe, I have a new module coming in tomorrow, universal unit I believe, so we’ll try that and it hopefully will start but wanted to ask if anyone else might have an idea or might now what’s going on, we planned to check my relays this week as well
 
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I have read through this several times and I'm confused. Not sure if this is a "no crank" problem or a "crank with no start" or a combination of both.

It would help me to understand if the verb "crank" is used to describe it when the starter cranks (or attempt to crank) the motor over.

I know that it is possible that when the starter is engaged while the motor is running this will turn the starter into a generator. Because of the large reduction gear on the starter, when driven via the motor this spins the starter very fast and can generate a large and possible damaging voltage. There is supposed to be a one way clutch on the stater to prevent this.

Let say that the starter did turn into a generator and generated a LARGE voltage that has taken out the other electronic devices.

If this were my car I would do a through visual inspection of the wiring harness looking for evidence of burnt wires. What we are trying to find out is WHY the original problem occurred. IE did two wires melt and short together? Which is sometimes the down side of long tube headers. Never the less something made the starter engage in the first place. IMO it seems unlikely to me that a bad alternator "caused" this. It seems more likely to me that the alternator was collateral damage from the original event.

The best recommendation I can give at this point is STOP replacing parts until you KNOW what happened and why. Otherwise it seems likely to me that the new parts will suffer the same fate as the old parts.

1996+ Crank with no start check list
https://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html

If by chance the car now has a "no crank" problem this will need different trouble shooting. But if this were my car I would start by confirming +12 volts at the starter solenoid with the key in the "crank" position.
 
If it would be any better I could put the events in short order of whatss been happening and I’ve checked under the car about 4 times now, there are no wires anywhere close to the headers and I’ve also checked for +12 volts at the starter am there is I’ve also checked the clutch safety switch and that also power running trough it but I don’t know if the switch is bad, I did a 10 amp fuse bypass on the switch and still no crank, and by no crank I mean the starter doesn’t cut on at all so turn key nothing happens
 
CONFIRM there is power in and out of fuse F1.3. Use a known good ground.

CONFIRM that fuse F2.6 has power in and out with the key in the CRANK position. Use a known good ground.

Do you hear the faint click of the battery junction box starter relay when the key is turned to the crank position?

If you can hear the starter relay click try swapping with another.

If the stater relay clicks, fuses are good and still no power at the starter solenoid, then there's a wiring FAULT between the starter and the starter relay.

1999-2004 MY fuse panel schedule:
https://www.allfordmustangs.com/for...r-swap-wont-fire-please-help.html#post2669271
 
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CONFIRM there is power in and out of fuse F1.3. Use a known good ground.

CONFIRM that fuse F2.6 has power in and out with the key in the CRANK position. Use a known good ground.

Do you hear the faint click of the battery junction box starter relay when the key is turned to the crank position?

If you can hear the starter relay click try swapping with another.

If the stater relay clicks, fuses are good and still no power at the starter solenoid, then there's a wiring FAULT between the starter and the starter relay.

1999-2004 MY fuse panel schedule:
https://www.allfordmustangs.com/for...r-swap-wont-fire-please-help.html#post2669271
Thanks a lot, I will check all of this today in a bit