Another Problem, Backfiring
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Joined: Nov 2006
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From: Wyoming
Another Problem, Backfiring
1994 Vette LT1. Well I have another problem. My last problem it was backfiring through the intake. I got a lot of advice from here and it ended up being a broke rocker. Ok, I just replaced the rockers with 1.6 rollers. I also replace the cap and rotor w/MSD, plugs ,wires, and installed a cold air intake. My new problem is it stalls, misses and backfires through the exhaust. It don't do it all the time, mostly after it warms up. It almost always happens right after WOT even if its still cold. It seems to idle fine when this problem occurs. I can shut it off and it always restarts with no problem. No smoke either.
I did flush the coolant system and ever since I did that I started having a over heating problem at slow speeds. The fan doesnt kick in until its around 250 or better. So this is another problem. I'm guessing a coolant sensor here. I was reading another guy (vettowner1994) on here with the same probem as above and someone said his missing problem could be a coolant sensor. So could a coolant sensor be my entire problem and if so which one?
Here are the trouble codes. A: 42,51,61,62
Thanks,
Steve
I did flush the coolant system and ever since I did that I started having a over heating problem at slow speeds. The fan doesnt kick in until its around 250 or better. So this is another problem. I'm guessing a coolant sensor here. I was reading another guy (vettowner1994) on here with the same probem as above and someone said his missing problem could be a coolant sensor. So could a coolant sensor be my entire problem and if so which one?
Here are the trouble codes. A: 42,51,61,62
Thanks,
Steve
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
1994 Vette LT1. Well I have another problem. My last problem it was backfiring through the intake. I got a lot of advice from here and it ended up being a broke rocker. Ok, I just replaced the rockers with 1.6 rollers. I also replace the cap and rotor w/MSD, plugs ,wires, and installed a cold air intake. My new problem is it stalls, misses and backfires through the exhaust. It don't do it all the time, mostly after it warms up. It almost always happens right after WOT even if its still cold. It seems to idle fine when this problem occurs. I can shut it off and it always restarts with no problem. No smoke either.
I did flush the coolant system and ever since I did that I started having a over heating problem at slow speeds. The fan doesnt kick in until its around 250 or better. So this is another problem. I'm guessing a coolant sensor here. I was reading another guy (vettowner1994) on here with the same probem as above and someone said his missing problem could be a coolant sensor. So could a coolant sensor be my entire problem and if so which one?
Here are the trouble codes. A: 42,51,61,62
Thanks,
Steve
I did flush the coolant system and ever since I did that I started having a over heating problem at slow speeds. The fan doesnt kick in until its around 250 or better. So this is another problem. I'm guessing a coolant sensor here. I was reading another guy (vettowner1994) on here with the same probem as above and someone said his missing problem could be a coolant sensor. So could a coolant sensor be my entire problem and if so which one?
Here are the trouble codes. A: 42,51,61,62
Thanks,
Steve
Re your over-heating, did you burp the cooling system to remove all the air?
Jake
Jake
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From: Wyoming
Yes rockers are adjustable. I adjusted them like I always do. Losen them until it rattles slowley tighten until it stops rattling then 1/4 turn tight. Some people go a 1/2 turn I go 1/4 turn so I'm pretty sure they aren't to tight.
Instructor
Joined: Jun 2006
Posts: 152
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From: louisville Kentucky
im wasnt sure of youre experience adjusting valves.ive made mistakes adjusting them before.it sounds like either an exhaust valve is open during combustion or or its firing out of sequence.did you adjust the valves engine running or static?an exhaust backfire usually indicates a rich condition,but you havent changed any fuel system parts.so imleaning towards valve not seating-plug wire sequence.
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From: Wyoming
I adjusted them with the engine running. I don't really think the problem is mechanical. It runs really good when its cold. Once the backfiring starts the engine stalls really bad to the point it almost dies. It almost acts like its out of time when I give it throttle. I can put it park or neutral and it idles just fine.
Instructor
Joined: Jun 2006
Posts: 152
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From: louisville Kentucky
im juggling here,my son is sick.i read youre description again and im guessing you have a factory opti distributor.you replaced the cap and rotor on it.im not sure how familiar you are with these ignitions but you didnt by chance get it wet did you?does it "the distributor" have a vacuum line going to it?
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Joined: Nov 2006
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From: Wyoming
Today I replaced the coolant sending unit and I rechecked the valve adjustment. I want for a spin around the block and it ran great until I got on it. After that it stalled, backfired and all that bad stuff.
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Joined: Nov 2006
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From: Wyoming
It ran fine today until I got on it. It will start miss firing, stalling and if I keep giving it gas it starts backfiring. It does it eventually even if I don't get on it, its just a matter of time. Can anyone help me out here. I'm getting ready to buy a new MSD opti. to see if that will fix my problem. I would hate to spend that much money and it not fix the problem.
Thanks,
Steve
Thanks,
Steve
