Ignition Problem- only under load...
10-07-2001, 01:21 PM
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Location: Sacramento, CA Age:25
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Car: 91 Formula, 92 Vert
Engine: 350 TPI, 350 LT1
Transmission: Both Auto
Ignition Problem- only under load...
I JUST put my motor back together and dropped it in the Formula. No problems at all. It runs good so far and I was putting my break in miles on it. I am treating the motor nicely but I do get on it a little to help the break-in and see if everything is ok.
Well, it would do fine under acceleration (load) until about 100 miles on the new motor it would stumble real bad and backfire and pop. As long as I keep off the gas uner 1/4 throttle it runs fine. I have had this problem before and found that under load I had a spark plug wire that would ground out through the insulation. Well I looked for that and could not find any wires doing so. I am going to change out the wires anyway since they are a lifetime warranty set.
Any other ideas what it could be?
------------------
Trevor Myhre
91 Firebird Formula-
Built 355 w/ ATI ProCharger P600B 12psi, 2 core intercooler.
Pro-Built Stage 3 700-R4 w/ Continental 2400 stall TC
C5 wheels and tires.
92 Firebird Convertible-
TBI 305 w/ L98 cam, MSD 6A, Open Element, Free mods
700-R4
WS6 wheels and tires.
Me, my car and I
"Speed kills but it makes me feel alive" - White Zombie
Crazy street-racing idiot member of the All-Powerful Nor-Cal crew.
Well, it would do fine under acceleration (load) until about 100 miles on the new motor it would stumble real bad and backfire and pop. As long as I keep off the gas uner 1/4 throttle it runs fine. I have had this problem before and found that under load I had a spark plug wire that would ground out through the insulation. Well I looked for that and could not find any wires doing so. I am going to change out the wires anyway since they are a lifetime warranty set.
Any other ideas what it could be?
------------------
Trevor Myhre
91 Firebird Formula-
Built 355 w/ ATI ProCharger P600B 12psi, 2 core intercooler.
Pro-Built Stage 3 700-R4 w/ Continental 2400 stall TC
C5 wheels and tires.
92 Firebird Convertible-
TBI 305 w/ L98 cam, MSD 6A, Open Element, Free mods
700-R4
WS6 wheels and tires.
Me, my car and I
"Speed kills but it makes me feel alive" - White Zombie
Crazy street-racing idiot member of the All-Powerful Nor-Cal crew.
10-07-2001, 01:40 PM
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Location: Rio Rico, AZ 85648
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Car: 1989 IROC-1
Engine: L98
Transmission: 700r4
Blown,
There are certainly much more qualified people than myself for this problem.......however, I had the same problem, and it turned out to be the ignition module. I'm not sure why, but a fault ignition module caused the same problem in my car about a year ago. I have had others go bad with out these symptoms, but definately had that problem.
Worth a shot.
There are certainly much more qualified people than myself for this problem.......however, I had the same problem, and it turned out to be the ignition module. I'm not sure why, but a fault ignition module caused the same problem in my car about a year ago. I have had others go bad with out these symptoms, but definately had that problem.
Worth a shot.
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