Fires then dies...
Thread Starter
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
Fires then dies...
Just completed a full blown brake job on the 73. Thought I'd take her for spin, and suddenly the engine will fire then quickly die. It was getting dark so I didn't spend much time diagnosing, but the q-jet is squiriting fuel as I operate the throttle by hand and it's not out of fuel nor is it flooding.
So, apparently, an electrical prob. I'm running a Petronix kit, their coil, and the rest is stock (I have run the Petronix kit on a half dozen cars,..no problems, ever).
She was running fine before the brake job. Tomorrow after work I thought I'd have the wife crank her while I hold and ground a spark plug and watch for spark.
Anything else to look for?
Thanks in advance,
Wes
So, apparently, an electrical prob. I'm running a Petronix kit, their coil, and the rest is stock (I have run the Petronix kit on a half dozen cars,..no problems, ever).
She was running fine before the brake job. Tomorrow after work I thought I'd have the wife crank her while I hold and ground a spark plug and watch for spark.
Anything else to look for?
Thanks in advance,
Wes
Thread Starter
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
SIXFOOTER,..thanks for responding. What is the 'RUN' circuit?...and what do I need to do to diagnose/fix?
I believe she has a resistor 'wire' to the coil?...is this what you're referring? If so, I'll check for voltage tomorrow.
Thanks!
I believe she has a resistor 'wire' to the coil?...is this what you're referring? If so, I'll check for voltage tomorrow.
Thanks!
Drifting
Joined: May 2003
Posts: 1,634
Likes: 2
From: Melbourne, Victoria, Australia, the World
If it dies immediately you turn the key from start to run (on) then the wire from the fuse box, which is a resistive wire, is broken, open circuit, or just plain fallen off the coil. Had this happen to me once where it would start then die as soon as you let the key off the start position. Wire had come off the coil.
Good luck!
Good luck!
Thread Starter
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
Yeah,..I need to check the resistor wire. Hope it's not the ignition switch. There's a wire from the starter solenoid to the coil,..I guess that's what's firing the engine initially,..then when the ingition switch is returned to "on" no current is reaching the coil. Does this agree with your diagnosis?
Thanks!
Thanks!
Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
Definitly sounds like the ballast circuit is dead, since you get fire while the switch is in 'start'.
I believe that if you are running the Pertronix module, it's recommended that you have a full 12v at the coil at all times, so if your ballast resistor is bad, just remove it from the circuit and get that full 12V.
I believe that if you are running the Pertronix module, it's recommended that you have a full 12v at the coil at all times, so if your ballast resistor is bad, just remove it from the circuit and get that full 12V.
Thread Starter
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
Update,..I got out my volt-meter and after I took off the chrome distributor cover, I noticed the coil-to-cap wire was severly twisted and bent (and old) caused by the the cover,..hadn't really noticed that before.
Went ahead and tested voltage from the resistor wire at coil and it was good, about 6.6v with the engine off.
So I decided to make another coil-to-cap wire with some spare plug wire and with 90 degree boots I had,..the one I was replacing had the straight up boots.
Made the wire (which fits much better under the cover), put it on, and one touch of the key and she's BACK IN BUSINESS!
PS Grunty,..73's don't have a ballast resistors,..only a resistor wire,..and yes, someday I'll replace it with regular twisted 12g.
Thanks for the help.
Went ahead and tested voltage from the resistor wire at coil and it was good, about 6.6v with the engine off.
So I decided to make another coil-to-cap wire with some spare plug wire and with 90 degree boots I had,..the one I was replacing had the straight up boots.
Made the wire (which fits much better under the cover), put it on, and one touch of the key and she's BACK IN BUSINESS!
PS Grunty,..73's don't have a ballast resistors,..only a resistor wire,..and yes, someday I'll replace it with regular twisted 12g.
Thanks for the help.
Last edited by 73, Dark Blue 454; Jun 19, 2006 at 11:32 PM.
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Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
Woo-wee! Aren't we fancy with our 'resistor wire'! I wouldn't know what to do with such a new car. ;-)
Seriously thanks for the information, I honestly haven't touched anything newer than '71. Glad you got it running though.
--- Edit ---
Just realized that both of my '69 chevys don't have a resistor, just the wire. Have to correct myself before someone does it for me.
Seriously thanks for the information, I honestly haven't touched anything newer than '71. Glad you got it running though.
--- Edit ---
Just realized that both of my '69 chevys don't have a resistor, just the wire. Have to correct myself before someone does it for me.
Last edited by GruntyPants; Jun 20, 2006 at 01:04 AM.