99 chevy c1500 5.7 vortec dies and I'm ready to kill it
Asked by Tim Aug 16, 2023 at 02:44 PM about the 1999 Chevrolet C/K 1500 LS Extended Cab RWD
Question type: Maintenance & Repair
1999 vortec 5.7. Runs fine
until just before getting to
operating temp, starts
missing, backfiring through
the exhaust then finally dies.
No start until completely
cold,or the next day. I've
replaced all the usual
suspects from fuel pump to
sensors. Help??
7 Answers
Has live data shown anything just before it dies out. I suspect a cam or crank sensor is going open due to thermal breakdown, I have seen a few ECM’s also do the same thing. That would show on a data scan.
I think those twenty-four year old, leaking injectors are due for a change. When an engine's cold, the excess fuel isn't so much a problem, but when warmed up, it floods the engine, sensing raw gas into the exhaust, causing exactly the troubles you've described. That excess fuel has also fouled plugs, making restarts a problem. Next time this happens, push the throttle to the floor, This signals the computer to do a wide open throttle (WOT) that clears out the fuel for a successful restart.
Answer will post shortly? Define shortly; it's now 24 hours.
Ignition coil, Ignition control module, coolant temperature sensor. Hope that helps! Jim
