95z115

So i am going 50 mph on my automatic LT1, steady throttle, and the car dies. It started right back up no problem, but why did it die? I have had problems a couple of weeks ago when it would die when i was sitting at a stop light at a complete stop. When i was stopped, it was like i took my foot off the clutch and didn't give it any gas (if i had a stick). Its not a everyday thing, just randomly.

Dave Feerst

need more info. Was there noises? jerking ? odors? did you do somthing to fix the problem last time?

95z115

No nothing really, just the motor tried to die, then came back , then tried to die, then came back, then died all within a matter of 1 or 2 seconds.

Dave Feerst

Well, thats a tough one but I'll start listing stuff

oh, btw, any codes?

Lets start with the fuel system...
Ususally when a motor runs out of fuel you hear it chug for awhile unless it is a fuel volume issue.
A clogged fuel filter is common and easy to check but it usually causes the motor to die on accel. Same with fuel tank pickup.
You can have acceptable fuel pressure and still have either of these problems....Fuel pressure and fuel volume are completely different.


If the pump it-self wears out you can have low or no fuel pressure. Doing a fuel pressure test or Low amps probeing test is easiest here if you have the equipment. I have heard of fuel pumps overheating and cars not starting on hot days but I dont think it would kill it like that.

Lets talk about the Air intake system....
A clogged air filter can cause it to die but you would be way down on power when it was running if it was that clogged.

A poor connection at the MAF could cause it to Die. You can check this just by unpluging it with the car off then starting it up. It will default to a speed density system, but if you un-plug it with the car running it will kill it. This will throw a code.

A Map sensor could cause it too but I've never heard of a LT-1 map sensor going out.

Ignition system....
Lets see, Im sure the opti could fail in some way to cause that problem. but usually if its the cap the motor has crossfire under load and if its the photocells the motor wont start at all, All though this could be intermitant if you had a loose connection on the optispark harness, the 4 wire connetion the goes up near the left side of the intake then over to the computer. If it was the sensor coming loose it would throw a code.


A overheating coil can cause a motor to die but usually it doesn't fire back up right away. If you had several burnt wires or fouled plugs It may die but it would run rough as hell when its running.

If your car is a 97 it has a cranksensor that could cause this problem. I think it would throw a code...

A stuck open EGR valve can cause a car to die at Idle but not while at 50 MPH I dont think. If your car is OBD 2 it should throw a code for this, if it is OBD 1 it may not....

Also a stuck open evap canister can cause the car to run rich and die, but again, usually only at idle... I don't think this would throw a code.

Im not sure on a few of the other sensors ECT ACT Im not sure if these failing would cause a LT-1 to die, never un-plugged them with it running.

Thats about All i can think of unless i get some more info....

C Man

If you're loosing power right away... with no other indication of problems, I would first check the ignition coil wire and then the coil itself.

It would be easy and cheap to replace and would do what you said the car has been doing.

My car actually died on the highway once..... then started up again as I was moving over to the side of the road. I was also getting some stuttering at high RPM... but it wasn't consistent.

I figured out after a little trial and error that the Coil wire was cracked and arcing... which caused a total lack of power. On rainy days, the problem was worse.... I even had a tough time starting it if it sat there for too long as the moisture built up.

Replace the wire first. It's a simple cheap fix if it's the problem.

Good luck and keep us up to date on everything.

95z115

Dave thanks alot for all the info. I had my spark plug wires changed last week because I had my car diagnosed and it said they were bad. Also in the diagnostics it said my EGR valve is bad, that was replaced as well. I will begin the process of elimination and check all the stuff you said. Thanks again

Cman, I had the wires changed and as far as the coil, a wire was lose, so they tightened it. I guess there could have been a crack and they didn't notice? Thanks