1995 LT-1 SHUTS DOWN AFTER 15 MINS.
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From: Ft.Myers Fl.
1995 LT-1 SHUTS DOWN AFTER 15 MINS.
Hope someone can help. I have a 1995 LT-1 w/383 with only 7k miles. This car always ran great !! After approx. 15 minutes engines appears to run out of gas, it bucks a couple of times, no backfire, then just stalls out. It cranks fine, but still will not fire!!! If I let it sit for a couple of hours it will start right up and run like new, but again after approx. 15 minutes, it dies out. ..... I ran a fuel pressure check while it was running, even after it stalled, the pressure remained NORMAL. I shut the key off, bled the FP gauge, cranked the motor and the pressure shoots right up to about 40 PSI........ next I checked the spark coming out of the plugs, "NO SPARK"...then I pulled the coil wire boot off and ran a test light, in line, coming OUT of the coil, still NO SPARK.......... I put in a new MSD Coil the next day. It cranked right up ran great sitting in my garage, but once again after about 15 minutes , I could hear a slight rpm increase for a couple of seconds, then it stubmbles and dies!!!!!! Do you think it could be the coil module?? By the way, about 1k miles ago I changed the OPTI SPARK, and installed an ELECTRIC WATER PUMP, h20 runs approx 190F. What next????????????? :smash: Mark
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Joined: Mar 2001
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From: Cincinnati, Oh USA
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (BLIZZ)
My money is on the spark control module in the distributor. It fails when it gets hot and recovers when it cools off (a fairly common occurrance). I would use the GM spark coil as it was designed to work with the spark control module. In a switched primary ignition system (like the vette system) the spark energy is 1/2 LI*2. You can increase the spark energy by increasing the primary current (I), but this will shorten the spark control module life. You can increase the spark energy by increasing the coils' primary inductance (L), but then this will cause decreasing spark with increasing rpm. GM's Hi energy ignition works great over the stock rpm range and who knows what compromises an aftermarket coil maker made?
[Modified by jfb, 5:27 PM 11/16/2003]
[Modified by jfb, 5:27 PM 11/16/2003]
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Joined: Oct 2001
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From: Larkspur CA
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (jfb)
That kinda sounds like the ESC module to me as well. There's a procedure in the various service manuals to test for it with a multimeter/test light.
I made the mistake of not using grease on the back of the module when I had the whole coil assembly disassembled. They runs about $100 for a new one.
Nick
I made the mistake of not using grease on the back of the module when I had the whole coil assembly disassembled. They runs about $100 for a new one.
Nick
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From: Ft.Myers Fl.
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (BLIZZ)
Thanks guys.... JFB, when you mention spark control module, where is that located??? I hope it is not in the OPTI.... I really don't feel like going through that "MESS" again, I didn't think the OPTI. was servicable! Nick, I hope It is only the ESC, I am going to look for the service test procedure in my shop manual. I will let you know. Thanks to all, God Bless, Mark. :crazy:
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From: Cincinnati, Oh USA
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (BLIZZ)
Sorry Blizz, I own an 87, no opti. I don't know what they call the module that pulses the primary of the spark coil in your car, but you should be able to find it in your shop manual.
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From: San Pedro CA
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (BLIZZ)
you are right... there is nothing serviceable in the opti. you can swap the cap/rotor, tho.
however, on the right head, next to the coil, is the Electronic Spark Module. Basically, a solid state relay to fire the coil. there is your bad part.
however, on the right head, next to the coil, is the Electronic Spark Module. Basically, a solid state relay to fire the coil. there is your bad part.
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From: Ft.Myers Fl.
Re: 1995 LT-1 SHUTS DOWN AFTER 15 MINS. (BLIZZ)
Hi Bogus, I just removed the Module from the Coil bracket. I am going to take it to my local dealer, I know the service Mgr., I'll see if a test can be done on it. The odd thing is, the dash didn't display any CODES when it dies! I sure hope that its just the Module and not the "OPTI "CRAP"! Like I stated earlier, only 1000 miles ago, $400.00 for the factory unit, and a lot of swearing and "busted knuckles to replace it! I just don't want to go through it again any time soon! The only good part was that when I put the Opti in, I went ahead and put in a Mezire Water Pump!!!! Well, I'll be @ the dealer tomorrow when they open. Thanks to all, Mark :thumbs:
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