[BowtieDieHard]

1999 Silverado, 1500ext, 5.7Vortec, 234,xxx mi. Had this happen several times over the 4 years I've owned it. Strong old 350 runs great, then starts missing for a few miles, then backfiring out the exhaust, then dead. Won't start. First time, mechanic replaced cap and rotor. I drove it probably 10k miles. Second time, same fix. Drove about 5k miles then parked it for a year due to health issues. Started it periodically to keep the battery up. A couple of months ago, I had it running, charging the battery, and it pulled the same trick. Started missing, backfiring, then died. No start. I put on a new cap and rotor. Fired right up. Drove it 15 miles ....yep. Same crap, AGAIN. This time I put a new distributor in along with a new cap and rotor. This time I got about 50 miles out of it before it did the same thing again. Luckily, I was in my front yard this time. (My ins. Co. is threatening to drop my tow coverage 😁). So, what do I target next? Coil? Fuel? Sensors? I'm pulling my hair out!!

 

[OpalLacod]

I'm assuming you're pulling the battery when to do work on it, so it could be resetting to factory fuel trim and timing. Do you have any codes when this happens? Misfire codes?

 

[j cat]

1999 silverado is a 5.3L engine .. now GM probably in 1999 changed the 5.7L to the 5.3L ..
your truck is not running ... you did not run it a full year ... then your gasoline is a goop .. inspect the fuel pressure.. take out the fuel filter cut open the filter then if it is goop in it then you have to take the gas tank out and clean it ...
5.7L engine is 60-65 psi gas pressure when you turn the key on no cranking ..

I looked it up a K1500 chevrolet truck 5.7L ...5L engine ..
silverado is the 5.3L 4.8L,,,,,,,,,,,, 4.3 V6 engine ..

 

[OpalLacod]

1999 silverado is a 5.3L engine .. now GM probably in 1999 changed the 5.7L to the 5.3L ..
your truck is not running ... you did not run it a full year ... then your gasoline is a goop .. inspect the fuel pressure.. take out the fuel filter cut open the filter then if it is goop in it then you have to take the gas tank out and clean it ...
5.7L engine is 60-65 psi gas pressure when you turn the key on no cranking ..

I looked it up a K1500 chevrolet truck 5.7L ...5L engine ..
silverado is the 5.3L 4.8L,,,,,,,,,,,, 4.3 V6 engine ..

According to RockAuto, the 5.7L is available in the 99 OBS truck (K1500, not Silverado). I would assume the 350 didn't make the transition with the body style transition in 99.

 

[BowtieDieHard]

1999 silverado is a 5.3L engine .. now GM probably in 1999 changed the 5.7L to the 5.3L ..
your truck is not running ... you did not run it a full year ... then your gasoline is a goop .. inspect the fuel pressure.. take out the fuel filter cut open the filter then if it is goop in it then you have to take the gas tank out and clean it ...
5.7L engine is 60-65 psi gas pressure when you turn the key on no cranking ..

I looked it up a K1500 chevrolet truck 5.7L ...5L engine ..
silverado is the 5.3L 4.8L,,,,,,,,,,,, 4.3 V6 engine ..

I'm well aware of the engine change. My truck is the 88-98 body style but manufactured 4/99. The 5.7 Vortec was born in the experimental stages that brought out the 5.3L v8. The ignition/timing systems are pure, plastic junk. I used Stabil in the tank. Hopefully I don't have to dump 3/4 of a tank, I think id cry. Thanks for the reply. I'll certainly check out the fuel filter.

 

[j cat]

I'm well aware of the engine change. My truck is the 88-98 body style but manufactured 4/99. The 5.7 Vortec was born in the experimental stages that brought out the 5.3L v8. The ignition/timing systems are pure, plastic junk. I used Stabil in the tank. Hopefully I don't have to dump 3/4 of a tank, I think id cry. Thanks for the reply. I'll certainly check out the fuel filter.

cut that fuel filter !!!!!!!!!! see if its goop ..alcohol is now in the gas and it is creating a mess over a few months .
I use my 20 ft wellcraft boat .. use marine gas stabilizer and use MMO oil ... my boat does not have a charcoal filtration air vent .. the gas tank has a air vent .. now back in the old days the vehicles have no charcoal air filtration to vent the gas tank..