1995 GMC C1500 engine cuts out then takes a few minutes to start. Pulling my hair out!

[Hobo]

My trucks engine cuts out as I am driving I have to pull over to the side of the road wait a few minutes and then it'll start back up if I try to start it right away it'll turn over but won't catch if I let it sit for a minute or two sometimes up to 15 minutes it'll turn right over. I've replaced the distributor, injectors, injector pressure regulator, fuel pump, fuel filter, gas tank, map sensor, throttle regulator, everything I know to change I've done and I have no idea what else to do. 1995 GMC C1500 ext cab 5.7

any Ideas?

 

[1998_K1500_Sub]

Any ECU codes? You mentioned none. Check them anyway, regardless of whether the "check engine" light is on.

When it fails to start as you describe, that's your opportunity to identify the problem. While you're along the side of the road have you...

- checked fuel pressure
- checked for spark
- made note of ambient conditions (high / low temps, high humidity, rain, etc.)
- noted any unusual dashboard gauge readings
- used a diagnostic tool, e.g., like DIACOM et al., to see what the ECU has to tell you during the time the engine fails to start


Does it misbehave in any other way at any other time...

- long crank before starting when cold, when hot,...
- failure to start under other conditions than already mentioned
- erratic engine behavior


Is the vehicle history a factor, e.g., comment on...

- rust or corrosion due to sea spray / winter road salt
- major body repairs (can lead to grounding problems)
- major power train repairs (trans swap, engine swap,...)


Sounds like you've replaced plenty of parts. But installing parts doesn't guarantee anything; for example, intermittent low fuel pressure can be due to a poor fuel pump ground and not simply the pump.

 

[Texvet]

Check the ground straps from the frame (pass side) to the engine and to the firewall under the evaporator. May not be the cure, but those need to be in good shape or all kinds of issues can arise.

 

[1997]

Any ECU codes? You mentioned none. Check them anyway, regardless of whether the "check engine" light is on.

good advice, OBD1 can set codes without turning on check engine light

 

[Pinger]

My trucks engine cuts out as I am driving

Are the rpms low when it quits? Is the engine up to temp before it quits?

I have to pull over to the side of the road wait a few minutes and then it'll start back up if I try to start it right away it'll turn over but won't catch if I let it sit for a minute or two sometimes up to 15 minutes it'll turn right over.

Quitting when hot and at low rpm (usually at a halt at a junction when the engine drops to idling rpm) then not re-starting for a short period are classic crank position sensor failure symptoms.

 

[PlayingWithTBI]

Quitting when hot and at low rpm (usually at a halt at a junction when the engine drops to idling rpm) then not re-starting for a short period are classic crank position sensor failure symptoms.

Could be, unfortunately he has a 95 TBI engine which doesn't have a CPS.

 

[Pinger]

Could be, unfortunately he has a 95 TBI engine which doesn't have a CPS.

Ahhh....

 

[Jeff Janssen]

I'd want to check for spark (easy enough to do on the side of the road) the next time it quits. spark/no spark is a diagnostic fork in the road, helping you eliminate a lot of unnecessary work.

 

[SUBURBAN5]

Could it be flooding out?

 

[Hobo]

Check the ground straps from the frame (pass side) to the engine and to the firewall under the evaporator. May not be the cure, but those need to be in good shape or all kinds of issues can arise.

gonna do that today