Unusual No Start Condition
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
Unusual No Start Condition
Just had some work done on my '97. Picked it up last Wed. I had new ARH headers installed with catted mid pipe, new shocks, new rear main seal, torque tube rebuilt, vacuum leaks fixed and some miscellaneous suspension stuff, and a fresh tune.
Car is LQ9 swap with a fairly big cam. I've driven pretty much every day since getting it back. Ran great, started right up every time.
Drove it to work today. When I went to start it to go home, when I turned the key, I heard a loud pop. Got out, checked for anything like fluids gushing out, smoke, fire, none of that. Checked under hood for charred bits, etc. Nothing. Go try it again, I get a small pop, however, I only turned the key to 'run', not start. tried it again, no pop, turned to start, it cranks, fires for a second, then dies. Occasionally, I would hear the small pop, but not every time, more random. Guys checking it with me didn't see anything unusual, no sparks, no smoke, nothing. For the brief second that it fires, there is no unusual noises.
I'm going to reach out to the guy that did the work, he's well regarded in this area, especially with C5's. But I thought maybe someone here as had a similar issue. Maybe it's so simple I can't see it, ya know?
Car is LQ9 swap with a fairly big cam. I've driven pretty much every day since getting it back. Ran great, started right up every time.
Drove it to work today. When I went to start it to go home, when I turned the key, I heard a loud pop. Got out, checked for anything like fluids gushing out, smoke, fire, none of that. Checked under hood for charred bits, etc. Nothing. Go try it again, I get a small pop, however, I only turned the key to 'run', not start. tried it again, no pop, turned to start, it cranks, fires for a second, then dies. Occasionally, I would hear the small pop, but not every time, more random. Guys checking it with me didn't see anything unusual, no sparks, no smoke, nothing. For the brief second that it fires, there is no unusual noises.
I'm going to reach out to the guy that did the work, he's well regarded in this area, especially with C5's. But I thought maybe someone here as had a similar issue. Maybe it's so simple I can't see it, ya know?
Le Mans Master
Joined: Jul 2010
Posts: 6,001
Likes: 722
Just had some work done on my '97. Picked it up last Wed. I had new ARH headers installed with catted mid pipe, new shocks, new rear main seal, torque tube rebuilt, vacuum leaks fixed and some miscellaneous suspension stuff, and a fresh tune.
Car is LQ9 swap with a fairly big cam. I've driven pretty much every day since getting it back. Ran great, started right up every time.
Drove it to work today. When I went to start it to go home, when I turned the key, I heard a loud pop. Got out, checked for anything like fluids gushing out, smoke, fire, none of that. Checked under hood for charred bits, etc. Nothing. Go try it again, I get a small pop, however, I only turned the key to 'run', not start. tried it again, no pop, turned to start, it cranks, fires for a second, then dies. Occasionally, I would hear the small pop, but not every time, more random. Guys checking it with me didn't see anything unusual, no sparks, no smoke, nothing. For the brief second that it fires, there is no unusual noises.
I'm going to reach out to the guy that did the work, he's well regarded in this area, especially with C5's. But I thought maybe someone here as had a similar issue. Maybe it's so simple I can't see it, ya know?
Car is LQ9 swap with a fairly big cam. I've driven pretty much every day since getting it back. Ran great, started right up every time.
Drove it to work today. When I went to start it to go home, when I turned the key, I heard a loud pop. Got out, checked for anything like fluids gushing out, smoke, fire, none of that. Checked under hood for charred bits, etc. Nothing. Go try it again, I get a small pop, however, I only turned the key to 'run', not start. tried it again, no pop, turned to start, it cranks, fires for a second, then dies. Occasionally, I would hear the small pop, but not every time, more random. Guys checking it with me didn't see anything unusual, no sparks, no smoke, nothing. For the brief second that it fires, there is no unusual noises.
I'm going to reach out to the guy that did the work, he's well regarded in this area, especially with C5's. But I thought maybe someone here as had a similar issue. Maybe it's so simple I can't see it, ya know?
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
I found a wire from the starter that was all buggered up, the casing appeared to be melted. My hypothesis is that when I took the wheel off on Sunday to fix the valve stem, this wire shifted too close to the header.
The thing is, that the starter cranks, and the engine fires, it just dies immediately. Then this morning, vats was in full force. In the past, before I changed the alternator, and removed some parasitic fuses, I would get the "pull key, wait 10 sec" message (there is an lcbm5 installed) the ignition system would do the same thing. It was always followed by vats kicking in. Once I changed the alternator it never returned.
So, I guess the plan is splice the starter wire, secure and insulate the wires, and get a heat shield for the starter. Jump the battery and make sure my insurance is paid up, just in case. All in the parking lot. lol.
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
So, how about a broken map sensor. I was reaching behind the manifold checking for loose connections and lo and behold, the map sensor was just laying there.
If I'm not mistaken, this would describe the crank, fire, stall issue, as having no map sensor might cause the pcm to cut fuel.
If I'm not mistaken, this would describe the crank, fire, stall issue, as having no map sensor might cause the pcm to cut fuel.
