redfishsc
Tired of fixing lousy engineering.
1999 Suburban 5.7. 250k miles
After a flawless 2,000 mile drive the week of Thanksgiving, now she doesn't want to start when cold. {EDIT: FOR CLARITY: Engine cranks over, but seems to get no combustion until 10-20 seconds of cranking. Then it spits, misfires, and knocks for a brief while, then suddenly runs perfectly.}
When warm, starts great, runs flawless.
Starter itself works fine.
Exhaust always smells rich. I've owned other 5.7 Vortecs that didn't smell this strong. Not quite "raw gas" but still smells strong to me.
It has seemed strong to me for a year or two, so maybe this isn't directly related to the non-start.
Injectors are upgraded MPFI, replaced when i redid the cylinder heads a few years ago (all stock)
Fuel pressure... 55psi with key on, engine off. Once running, it's 50 psi.
Fuel filter is probably 4 years old and WILL be replaced soon but I'm suspicious that this could be the issue since it runs great at wide open throttle.
The only engine code is EVAP. I don't smell raw gas around the truck.
O2 sensor front bank, both report an average of 0.7v once engine warmed.
Coolant temperature sensor (OBD2) is giving accurate readings (can read via torque pro app) and matches what's reported on the dashboard by the other sensor.
I'll report back later what the fuel pressure does after sitting for a while.
If I end up replacing the fuel pump, is there an additional sock filter I should be buying?
After a flawless 2,000 mile drive the week of Thanksgiving, now she doesn't want to start when cold. {EDIT: FOR CLARITY: Engine cranks over, but seems to get no combustion until 10-20 seconds of cranking. Then it spits, misfires, and knocks for a brief while, then suddenly runs perfectly.}
When warm, starts great, runs flawless.
Starter itself works fine.
Exhaust always smells rich. I've owned other 5.7 Vortecs that didn't smell this strong. Not quite "raw gas" but still smells strong to me.
It has seemed strong to me for a year or two, so maybe this isn't directly related to the non-start.
Injectors are upgraded MPFI, replaced when i redid the cylinder heads a few years ago (all stock)
Fuel pressure... 55psi with key on, engine off. Once running, it's 50 psi.
Fuel filter is probably 4 years old and WILL be replaced soon but I'm suspicious that this could be the issue since it runs great at wide open throttle.
The only engine code is EVAP. I don't smell raw gas around the truck.
O2 sensor front bank, both report an average of 0.7v once engine warmed.
Coolant temperature sensor (OBD2) is giving accurate readings (can read via torque pro app) and matches what's reported on the dashboard by the other sensor.
I'll report back later what the fuel pressure does after sitting for a while.
If I end up replacing the fuel pump, is there an additional sock filter I should be buying?
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