This is topic Kinda baffled here.. No spark 5.0 in forum Tech Talk at Northern California Ford Owners  .


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Posted by At1Maverick69 (Member # 6177) on :
 
I don't spend a lot of time diagnosing foxes and I am kinda stuck on one here. Working on a friend's 91 GT and so far I've replaced the pick up coil in the distributor, based on some previous experience.

I advised him to replaced the aftermarket coil he has on it(Accel), and put a stocker one, and replace the ignition module as well.

The other odd thing I notice was when turning the ignition on, fuel pressure goes up to 40psi but once you turn the key off it drops down to zero instantly, isn't it supposed to hold some pressure for a bit? Unless it has a leaky injector/regulator or something, right?

The car has the following mods:
-GT40 tubular intake
-adjustable FPR (not sure of brand)
-24# injectors
-higher flow fuel pump (unknown brand as well)

The car has had these mods for awhile, and was driven regularly until he was unable to make it pass Nevada emission a year ago, and it sat since then, he then installed a battery on it and that's when the problem started

THANKS FOR ANY HELP CAFORDS!!!!!!
 
Posted by ECOboostin (Member # 4347) on :
 
I'd focus on the spark issue for now. Since its an aftermarket fuel pump it could be missing a check valve as mine was and let the fuel pressure drop right back to 0 after prime. No issue there really as long as the car is started as soon as its being primed.
 
Posted by lxhatch5.0 (Member # 6319) on :
 
I think once u turn the key the pump starts priming automatically. It does on mine.

Check if u have spark by unpluging each plugg one by one and see iff sparks flash. If it does it mite be a bad fuel pump? Maybe it was instralled wrong u never know the basic shit always seems to be overlooked [burnout]
 
Posted by lxhatch5.0 (Member # 6319) on :
 
Change the battery to a different one, i seen that on ur first post just right now. Take one out from a known working running car that might be the issue. Do that first before u start swapping more parts.

[ August 11, 2012, 01:17 AM: Message edited by: lxhatch5.0 ]
 
Posted by At1Maverick69 (Member # 6177) on :
 
yup, I put my own battery from my Mach in it for a second, and has a new battery now too, still does the same thing, cranks but doesn't start.

And I think I forgot to mention that I pulled the wire from the coil and there was no spark from there, and none from the #1 cylinder. I ran a test w a volt meter a month back to test the pick up coil, that's why i told him we should start with that.

And the fuel pump primes just fine I think, cuz like I said it gets 40psi when u turn the key on.
 
Posted by At1Maverick69 (Member # 6177) on :
 
quote:
Originally posted by ECOboostin:
I'd focus on the spark issue for now. Since its an aftermarket fuel pump it could be missing a check valve as mine was and let the fuel pressure drop right back to 0 after prime. No issue there really as long as the car is started as soon as its being primed.
I tried to do it both ways, right after I hear the pump prime, and wait a couple of seconds, and came up with the same results. And I remember noticing that when cranking, the pressure drops almost to zero as well. But ya, like you said, I'm trying to focus on the spark issue first.

[ August 11, 2012, 01:34 AM: Message edited by: At1Maverick69 ]
 
Posted by racsirx (Member # 1710) on :
 
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
 
Posted by At1Maverick69 (Member # 6177) on :
 
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
Lee, Thanks I'll look into those. What color wire is that fusible link in, by the way?
 
Posted by racsirx (Member # 1710) on :
 
quote:
Originally posted by At1Maverick69:
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
Lee, Thanks I'll look into those. What color wire is that fusible link in, by the way?
I don't remember what the colors the wires are but almost wire coming off the positive side of the solenoid has a fusible link on it, but since the the battery was just changed and the problem came after that, check the negative cable with the weird connector on it to see if that is your problem, I had a convertible come in this week with a bad ground connector on it which gave low voltage to the fuel pump and no spark.

[ August 11, 2012, 03:19 AM: Message edited by: racsirx ]
 
Posted by turbo50 (Member # 6700) on :
 
quote:
Originally posted by At1Maverick69:
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
Lee, Thanks I'll look into those. What color wire is that fusible link in, by the way?
Yellowish orange color
 
Posted by dohc90lx (Member # 11863) on :
 
did you say you replaced the tfi already?
 
Posted by At1Maverick69 (Member # 6177) on :
 
Dan- THANKS!! I'll be checking that out tomorrow

DOHC90lx- Not yet, but I did advise him to replace just to rule it out.
 
Posted by BAD ASS 5.HO (Member # 10947) on :
 
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
+1

Make sure ur computer has power. Idnt know how other peopke do it but i check for a click on the passenger side kik pannel. That tells me the solonoid for the ecu has power. Rather not u would have to check for grounds and fusible links. theres a couple of reasons ur not getting spark. Bad evu,no ground,bad dizzy module,bad coil, faulty wiring. jst tryna help.

[ August 11, 2012, 11:00 PM: Message edited by: BAD ASS 5.HO ]
 
Posted by BAD ASS 5.HO (Member # 10947) on :
 
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
+1

Make sure ur computer has power. Idnt know how other peopke do it but i check for a click on the passenger side kik pannel. That tells me the solo.oid for the ecu has power. Rather not u would have to check for grounds and fusible links.
 
Posted by At1Maverick69 (Member # 6177) on :
 
quote:
Originally posted by BAD ASS 5.HO:
quote:
Originally posted by racsirx:
I would check the fusible links next to the solenoid and the ground next to the battery which has that detachable connector on it.
+1

Make sure ur computer has power. Idnt know how other peopke do it but i check for a click on the passenger side kik pannel. That tells me the solo.oid for the ecu has power. Rather not u would have to check for grounds and fusible links.
Thanks for the input, man. I'll check those too
 
Posted by At1Maverick69 (Member # 6177) on :
 
Thanks to everyone for the information. I'll be checking it out more tonight. [patriot] [patriot] [patriot] [patriot] [patriot]
 
Posted by At1Maverick69 (Member # 6177) on :
 
UPDATE! I was only able to check the yellow wire with the fusible link on it with a DVOM and there wasn't any continuity across it. So I went and tried to get a replacementat Napa, but they had only a 12gauge wire. From a diagram off Stangnet, I thought I saw it being a 10g. There wasn't anything written on the insulator. Can anyone verify?

Oh ya, I replaced the coil, but I wasn't able to try to crank it again.
 
Posted by At1Maverick69 (Member # 6177) on :
 
Well, replaced the fusible link and now have continuity on every wire that has one on the relay. Replaced the ignition module, the coil, and the pick up in the dizzy. Found a loose ground by the battery as well and put a new eyelet on it and grounded it. BUT still NO spark.

Anything else I'm missing?
 




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