1985 CONFUSING STALLING problem
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ok sounds like that may be the next thing I look at, I believe the wires are green and white. That's crazy about the tunnel story haha. What should the wires ohm at while wiggling?? what makes a pickup coil go bad?
Racer
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From: Alpine California
Green and white sound kinda familiar too, the insulation breaks down on them and allows them to short, thats why you have to wiggle them. I'm not an electrical genius (so if I get this wrong, somebody jump in and correct me), but I don't think you need a specific reading, your just checking for continuity, and for a possible short. All this is is a magnetic switch, the voltages induced are pretty tiny.
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well....kinda bad news...the problem seems to have regressed, while I was gone for the weekend my mechanic said the car died on him a few times in a row, and the car would NOT start up right away and had to wait for a few minutes before he could start it...could the module have failed again??? this is just getting stupid now
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had a discussion with mechanic, he believes strongly it could be a bad ground causing these problems, can anyone support that? The main thing he noticed is that the fuel pump doesn't always power on with the key turned to the ON position, as it is supposed to, and those are the times when the car will not start right up and maybe take a few minutes to be able to start. At the other times when the pump DOES come on, it starts up right away as it should, good and strong. Anyone know where I should go from here?
Le Mans Master
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From: seattle WA
One step at a time. Re; pickup coil, it should read a steady 500-1500 ohms while wiggling the wires, he should also connect the ohm meter to each terminal of the pickup coil and ground it to the distributor base..it should have an infinite (OL) reading on the digital ohm meter.
Since you're back in the dist. it wouldn't hurt to run that ign. module back down to NAPPA, highly unlikely it failed..but you wouldn't be the first to get a bad one.
Two other things I'd have him check 1. behind the battery is a power terminal..several wires attached, make sure they're clean and tight! one of these is a fusible link which provides power to the FP relay and also the oil pressure switch.2, I'd have him check to make sure the connections to the ECM are clean and tight.
The fuel pump relay will not come back on in less than 10 seconds.So, if you turn the key to ON, you should hear it energize, but if you turn the key off and right back on you will not.Hope this helps.
Since you're back in the dist. it wouldn't hurt to run that ign. module back down to NAPPA, highly unlikely it failed..but you wouldn't be the first to get a bad one.
Two other things I'd have him check 1. behind the battery is a power terminal..several wires attached, make sure they're clean and tight! one of these is a fusible link which provides power to the FP relay and also the oil pressure switch.2, I'd have him check to make sure the connections to the ECM are clean and tight.
The fuel pump relay will not come back on in less than 10 seconds.So, if you turn the key to ON, you should hear it energize, but if you turn the key off and right back on you will not.Hope this helps.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by masterprice33
had a discussion with mechanic, he believes strongly it could be a bad ground causing these problems, can anyone support that? The main thing he noticed is that the fuel pump doesn't always power on with the key turned to the ON position, as it is supposed to, and those are the times when the car will not start right up and maybe take a few minutes to be able to start. At the other times when the pump DOES come on, it starts up right away as it should, good and strong. Anyone know where I should go from here?
Le Mans Master
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From: Louisiana
Yes, this could all be over a loose ground/open circuit. On my 86, I can turn the key on and off as many times as I want and hear the fuel pump prime. The power supply wire/ground wire on the fuel pump assembly, in the tank, could be loose causing the pump to cycle on and off. I would take the igniton module to Napa and have them check it again too make sure. Attach a fuel pressure guage and drive. Test the fuel pump connection harness while wiggling, light should be bright the whole time. You will have to use the hot wire terminal G to get power to the pump for more than 2 sec. When the key is turned on it will only send power to the pump for 2 sec then it cuts off.
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Race Director
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From: Indianapolis IN
Originally Posted by masterprice33
had a discussion with mechanic, he believes strongly it could be a bad ground causing these problems, can anyone support that? The main thing he noticed is that the fuel pump doesn't always power on with the key turned to the ON position, as it is supposed to, and those are the times when the car will not start right up and maybe take a few minutes to be able to start. At the other times when the pump DOES come on, it starts up right away as it should, good and strong. Anyone know where I should go from here?
My 85 had ground issues too so I ran a 2 gauge ground from my battery to the chassis, then daisy chained another 2 gage up to the driver side head.
Racer
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From: NORFOLK VA.
It could be a bad pickup coil when it stalls does your mechanic check to see if it has spark at one of the sparkplug wires?Also does your mechanic have a noid light if so when the car is in a no start condition plug the noid light into the injector harness and crank the car if the noid light flashes that will let you know that the computer is signaling the injectors that still doesnot say your computer is ok because they can some time work some fuctions and not others,your computer could be bad and not know its bad and not show a code indicating its bad.I have seen it happen on more than one occasion
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Alright, again thanks EVERYONE for the detailed input, this must be getting frustrating for you guys i bet. I want this to be over! but i'm being extremely patient. I'll try to report back whenever I can get him to perform these tests, and I ordered a new pickup coil for like 10 bucks on ebay should be here in a few days, but will perform everything else suggested this week or weekend sometime.
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Just a little info for everyone that gave advice. In the beginning of all this, when we thought it was the fuel pump, mechanic noticed that fuel pump wasn't turning on with the ignition in the ON position, so he installed a manual switch to the fuel pump, that gets the fuel pump to turn on so that the car will run. So I don't know if that helps at all.
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no, pretty much back to square one. waiting on the pickup coil, and in the meantime still going over things we've tried before. Seems like too many angles to go from, do you know of a FSM that is relatively cheap anywhere?
Racer
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From: NORFOLK VA.
Originally Posted by masterprice33
no, pretty much back to square one. waiting on the pickup coil, and in the meantime still going over things we've tried before. Seems like too many angles to go from, do you know of a FSM that is relatively cheap anywhere?
LATERRR
Le Mans Master
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From: seattle WA
Look on ebay, just make sure you get the ones for your year! And with the trouble shooting guides they provide...your problem most likely would have been resolved by now, and for alot less $$....sorry.
Last edited by rick lambert; Jul 7, 2006 at 03:32 PM.
