Wont start? Idle? Wiring?
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Car: 1985 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: garbage 2.73
Wont start? Idle? Wiring?
Had an issue where the car would just die while driving. The car would stop like someone turned it off. Finally found the issue. There is a tan wire coming out of the main engine harness going to the coil. It was grounding against the valve cover, causing it to die. The wire isnt broken, so I put some plit loom around it to insulate it. Car started right up. I then decided to bump the idle set screw since it would idle at 500 rpms in gear. That is where the problems started. Within 3 seconds of barely adjusting the idle, the motor slowly died. I decided to set it back and the car wouldnt start. Make a long story short, had to push it out of traffic 4 times, drove 5 miles with the IAC disconnected(only way it would start). With IAC, it would die within a few minutes. Best chance was no IAC. The last time I got it running, I had the IAC connected, and came straight home. Could that damn tan wire be causing the motor to not start due to breaks in the insulation if its too close to the valve cover, but no noticable arcing? FYI, car is 305 TPI with separate coil from the cap. Going to splice in some new wire for that old crap. This is my work car, so have to get it running!
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Car: 1985 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: garbage 2.73
Re: Wont start? Idle? Wiring?
UPDATE
I replaced that wire, which is actually yellow and goes to the gray connector on the coil. Car started right up. steady idle at 750 in park. Ran for about 15 minutes, then decided to tempt fate by shutting it off then restarting it. It cranks, but wont turn over. After 2 attempts, went back to the coil because im THINKING its a spark issue. Made sure everything was tight, turned it over, had a slow start, but it started. Still running. Kinda scared to turn it off. Anyone have any ideas? Could this wire shorting against the valve cover burn out the coil? Oh, I looked up the diagram, that white wire goes to the instrument cluster? Im lost.....
I replaced that wire, which is actually yellow and goes to the gray connector on the coil. Car started right up. steady idle at 750 in park. Ran for about 15 minutes, then decided to tempt fate by shutting it off then restarting it. It cranks, but wont turn over. After 2 attempts, went back to the coil because im THINKING its a spark issue. Made sure everything was tight, turned it over, had a slow start, but it started. Still running. Kinda scared to turn it off. Anyone have any ideas? Could this wire shorting against the valve cover burn out the coil? Oh, I looked up the diagram, that white wire goes to the instrument cluster? Im lost.....
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Car: 1985 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: garbage 2.73
Re: Wont start? Idle? Wiring?
Any ideas? COuld the idle bee too low? Its 500 rpm in gear, 750 in park.
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Car: 84 trans am
Engine: 305 5.0L HO
Transmission: TH350
Re: Wont start? Idle? Wiring?
when it's dying do you still have tach.
I'm thinking the wire that goes to the cluster is the tach wire.
I might be wrong though.
Sounds electrical but who knows.
Do you have any way to monitor fuel pressure?
Have a spark tester? They are fairly cheap to keep on hand for such occasions.
Wish you luck with it.
I'm thinking the wire that goes to the cluster is the tach wire.
I might be wrong though.
Sounds electrical but who knows.
Do you have any way to monitor fuel pressure?
Have a spark tester? They are fairly cheap to keep on hand for such occasions.
Wish you luck with it.
#5
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Car: 1985 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: garbage 2.73
Re: Wont start? Idle? Wiring?
Yea, its for the tach. I drove all the way home today keeping the gas down to keep the idle at about 1k. Never died. Got home and readjusted the idle to sit at 750, so I figure itll be ok. Thanks for the info astro.
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