[Geese1]

Recently got back from my trip out to Utah with the car, and haven't driven it since then. Didn't have any problems with the car when on vacation, and it was working flawlessly. Had it parked for about a week and then moved it out of the garage to the driveway as I needed the garage space to finish detailing the new Mazda3 we picked up.

Car sat outside for about another week (with me not driving it) and then this past weekend I started her up to move her back into the garage and that's when the issues started.

Car had a lot of trouble turning over and it took a couple of times for it to catch. When it finally did turn over, the check engine light and traction control light were on, and I was getting the "reduced engine power" message on the display and in the HUD.

Had an appointment today to get the state inspection and warranty work on the lighted driver's sill (which isn't lighting up), so I called the dealership to give them a heads up and they asked me not to clear the codes as they wanted to see what they were (I had ordered an OBD II code reader before calling them). Brought it in today, and these are the codes they pulled:

P0090 - Fuel Pressure Regulator Control Circuit
P00C6 - Fuel Rail Pressure Low During Engine Cranking
P00C8 - Fuel Pressure Regulator High Control Circuit Open

All of these are current, with failure codes of 0x00

There were also 3 codes in history that they didn't think applied to this situation, but they were:

C0242 - Powertrain Control Module Indicated Traction Control
U0140 - Lost Communication with Body Control Module
U0184 - Lost Communication with Radio

Once again, all of these had a failure code of 0x00.

The dealership I brought it to is actually a Buick GMC dealer, and they didn't feel comfortable working on the engine with these codes as he said their techs were only really familiar with the 6.2 liter engines in the trucks, and he didn't want them to mess up anything on the Camaro engine. He did call over to their sister Chevy store (who I didn't really want to bring the car to if I could help it), and they wouldn't be able to look at it until next month, and even then they didn't have any techs who had experience working on this engine either.

I ended up calling the dealership I bought the car from, who is about 1.5 hours away from me, and they set up an appointment for the 19th of this month, although they did say I could drop the car off earlier and they could keep it in their service bay until they could work on it. They are also going to do the warranty work on the lighted door sill, and also (hopefully) the recall on the rear park assist, which this other dealer has been unable to get the parts for.

The car isn't a daily, so being without it for a while doesn't bother me, but I was just wondering if anyone had experience with what might be wrong. I don't know if I should try clearing the codes or if I should leave it all active for the dealership. I did fill up right before getting home at a gas station I don't normally use, so I'm wondering if I just got a batch of bad gas? Or maybe sitting outside for a while did something to make the car not want to start right away and that is what caused the fault.

Any insight into this would be appreciated.

[Mark114]

Originally Posted by Geese1

Car had a lot of trouble turning over and it took a couple of times for it to catch. When it finally did turn over, the check engine light and traction control light were on, and I was getting the "reduced engine power" message on the display and in the HUD.

If the engine had trouble turning over then maybe a low charge or bad battery? When the battery died on my Camaro it threw a bunch of failure codes.

[Geese1]

Originally Posted by Mark114

If the engine had trouble turning over then maybe a low charge or bad battery? When the battery died on my Camaro it threw a bunch of failure codes.

The dealership I had it at initially suggested that might be the case when I first called them, so I had it on a charger for the past few days to make sure there was a full charge. It was reading low when I first put it on, and it took a little longer than normal to get up to green, so that may have been the problem. None of the codes read anything related to the electrical system (from what I can see) though, and the CEL was still on when I drove it to and from the dealership today, and it didn't clear itself if that was what the problem is/was.

I'm tempted just to clear the codes myself, but I don't want to do that if its going to cause issues with driving it, or with the proper diagnosis of the fault.

[Mark114]

When my battery died it set the check engine light and a dozen or more random error codes. In my case I knew it was the battery so I replaced it and cleared the codes. After clearing the codes the check engine light turned off and the car seemed to be fine, but there were still several “permanent” codes listed. After a half hour drive I checked and all of the remaining codes were cleared.

In your case you’re already working with the dealership so I wouldn’t do anything to the car without talking to them first.

[SSDan]

These cars do weird things and throw weird codes when they have a low voltage battery.

Your call on cancelling the codes but I’d be tempted to do so now that the battery is back to full charge. If you are like me taking the car in for warranty repairs is something I’ll avoid if at all possible. Good luck.

[Geese1]

Originally Posted by Mark114

When my battery died it set the check engine light and a dozen or more random error codes. In my case I knew it was the battery so I replaced it and cleared the codes. After clearing the codes the check engine light turned off and the car seemed to be fine, but there were still several “permanent” codes listed. After a half hour drive I checked and all of the remaining codes were cleared.

In your case you’re already working with the dealership so I wouldn’t do anything to the car without talking to them first.

Yeah, maybe I'll call them tomorrow to see if they'd like me to try clearing the codes or leave them as is.

Originally Posted by SSDan

These cars do weird things and throw weird codes when they have a low voltage battery.

Your call on cancelling the codes but I’d be tempted to do so now that the battery is back to full charge. If you are like me taking the car in for warranty repairs is something I’ll avoid if at all possible. Good luck.

I hate the thought of brining it in for warranty work too, but they do need to look at the driver's door sill that's not lighting up, as well as try to get the parts for the retrofit on the rear park assist, so it will be going to them either way. They even asked me if I wanted to use my complimentary oil change since it will be expiring in a few weeks and I declined. The less they have to monkey around with my car, the more comfortable I'll be.

[ctrlz]

If battery voltage is good, I would look for signs of rodent activity in engine bay. May have chewed some insulation. The pattern sounds like wiring/communications.

[Geese1]

Originally Posted by ctrlz

If battery voltage is good, I would look for signs of rodent activity in engine bay. May have chewed some insulation. The pattern sounds like wiring/communications.

Thanks, that's something to look into as well since the car was sitting outside for a week. We've never had any issues with our other cars that aren't garaged, but that doesn't mean it didn't happen in this instance.

I did speak with the dealership this morning, and they said to go ahead and leave the codes in as that way they'll be able to see exactly what's going on. The service advisor said that sometimes they can still see the past code history when they're cleared, but not always. He also said that they've had trouble with some of these motors regarding the fuel system getting clogged, so that's something they'll check as well. I'll drop the car off next Saturday since the actual date they're scheduled to look at isn't until the 19th (a Wednesday), but being their an hour and a half from me it's not easy to get up their during the week, and I would also need to have my wife follow me up with one of our other cars so that she can take me home in case it takes longer than one day. Luckily, they did say that any of the Camaros or Corvettes that are dropped off for service are kept inside the building and not out in the open lot.

[Gunkk]

95% chance the dealer tech's writeup will be:
1. checked <insert one or all codes> and could not verify fault.
2. cleared codes, disconnected battery for 10 mins.
3. start up OK, test drive OK. No CEL, No codes.
and they'll hand you back the keys telling you your car is fine and send you on your way.

50% tossup on whether they replace the battery, which was probably just discharged. As said above a few times already, low battery voltage will cause all kinds of false alarm Pcode chaos with the modules in the car. Seen it myself with mine. I cleared a handfull of codes after a low battery no-start and they never came back.

[Geese1]

Originally Posted by Gunkk

95% chance the dealer tech's writeup will be:
1. checked <insert one or all codes> and could not verify fault.
2. cleared codes, disconnected battery for 10 mins.
3. start up OK, test drive OK. No CEL, No codes.
and they'll hand you back the keys telling you your car is fine and send you on your way.

50% tossup on whether they replace the battery, which was probably just discharged. As said above a few times already, low battery voltage will cause all kinds of false alarm Pcode chaos with the modules in the car. Seen it myself with mine. I cleared a handfull of codes after a low battery no-start and they never came back.

My thoughts are this is exactly what they'll find, but since I have to have the car in for some warranty work anyway I might as well have them look at it just in case it's something more serious.

[Geese1]

Just an update.

Picked up the car today. It was actually damage to the wires that was caused by rodents (ctrlz called it). They had to get in there and repair/replace the wiring harness. Unfortunately, because of this it wasn't covered under warranty and I had to pay out of pocket. But thankfully, the car is back to full health now. We've never had any issues with rodents before, even though we have two cars that normally sit outside (the Camaro and my wife's Saturn Sky are usually the ones kept in the garage), so I'm wondering if this may have happened at some point when I took the car out to Utah?

They also replaced the driver's side illuminated door sill that wasn't working. That was covered under warranty, so that was all good.

They're still waiting on the rear park assist retrofit. The part is still showing on national backorder. I'm keeping my order for the part in with the original dealer and with this one as well. Hopefully, that will give me a good chance to actually get it done before the car gets put away again for the winter.