Nomader33

On the way to work this morning, I stopped to buy a cigar at 0645. When I got back into my car and started it, it sounded like it was running on 4 cylinders. I shut it down and after a moment attempted to restart it. This attempt the car continued to turn over and acted like it was getting no fuel. I know, must be the fuel pump, but it was just changed out the end of March this year ( for the same thing). I arranged to get it towed to the dealer and called them to give them the symptoms. The tow truck was set up to pick my 2009 base C6 at approximately 1100. I went back to the car about twenty minutes early to get personal stuff out of the car. I figured I would give it one more try - it started! Drove it to work and let it sit the rest of the day. At the end of the work day went out to leave and car started properly. Car has a full tank. Battery is good. Thoughts?

Don-Vette

Like most everything thing else, sounds electrical. I know when the crank position sensor goes bad it will just turn over but not start. Hmmm....

EVRose

Failing fuel pump relay.

Nomader33

Just tried it again, and it cranked like only half of the cylinders got gas. Shut it down, attempted another start and it just cranks.

Treadhead

Yep, fuel pump relay. Take it out and look at the pins/blades for signs of burn. I replaced one that went bad(same symptoms as yours). My new one started doing the same thing after a year. The pins of the relay had burn marks, so I took some fine grit sand paper and cleaned them off, haven't had a problem since.

Nomader33

Checked relays-all good. Even swapped them around to no avail. I thought it might be heat related, but that was flawed. So, I bought a code scanner to see if it was tripping a code, nothing. Next step, going to check fuel pressure.

Nomader33

Put a fuel gauge on it yesterday, it showed 0 psi until I hit the start. The fuel pressure went to 60 psi immediately then dropped to to 30 psi for a few seconds. It then jumped up to 52 psi. Everything looked great, so I shut it down. Restarted it with no issues. So, I took it to Advance Auto Parts and had them check the battery. Everything checked fine. Car worked great Saturday. Sunday I went out to check it, and again, it just cranks over. I took the cap off of the fuel rail and depressed the Schrader and found nothing. Swapped relays, rechecked all of the fuses - everything looked good. Out of the 10 attempts to start it today, I had 1 P0230 code. Cleared it and did not get it again, but car will not start.

B y r o n

Maybe this will help.

Nomader33

Took it to the dealer! They troubleshot it to a bad sub-harness. No ground to the fuel pump. Picked it up today.

icntdrv55

Smoking cigars is unhealthy. You should quit.

bojangles

My dealership just installed a new starter. They wrapped the starter with an asbestos blanket. They said the heat from the engine was causing the problem. We'll see if that is true.

AORoads

that's interesting. any idea where this sub harness is located? would be helpful to know. glad it's fixed.