karl18d

Just ran my 2011 Rubicon Unlimited on a 231 mile highway trip, home, last night. Cruised at 75mph no problem. I ran low-beams, radar detector, and the stereo up; but don't think it was draining the Optima battery too bad.
I got up this morning for a drive, and after a quarter mile, I got the Red Lightning Bolt and Check Engine Lights. Drove home in limp mode.

Checked the Codes:
P0652 - Sensor Reference Voltage 2 Circuit Low
P2127 - Accelerator Pedal Position Sensor 2 Circuit Low
P0405 - Egr Position Sensor Circuit Low
P0340 - Camshaft Position Sensor Circuit
P0868 - Line Pressure Low

Now I don't know much about these separate systems. It seems like a wide spread for just one bad sensor.

Do any of you Freaks have an idea or suggestion of where I should start?

Thanks in Advance,
Karl18d

3min3m2

Got a multimeter? Check battery voltage, then if possible compare it at one of the sensors (easiest to reach). Could be wiring issue, battery, etc.

jchappies

Did it barely start?

karl18d

Barely starts and runs rough... definitely in Limp Mode.

Searched the Archives; Checked all Grounds; replaced PCV valve and Camshaft Position Sensor, with no improvement.

It mentions reset of Computer. However, I have a Superchip 87 Octane tune (ran great for years). Will a computer reset mess things up? I thought about resetting the tune to factory, before going to Dealership, but scared it will really screw sh!t up then.

Thinking about taking to Dealership, but they can't fit me in until Monday.

Vladimer

If you do take it to the dealer, make sure you reset your flashpaq to 100% stock. You can check it by plugging it back in and it should boot up without saying it is locked to a vin.

Otherwise when the dealer updates the cpu, they wont have an issue, but when you plug your flashpaq back in it will say the backup file doesn't match and it is essentially bricked. Superchips can reset it but its some stupid amount, $100+ or something plus shipping

Vladimer

Also, resetting it to stock cannot mess it up really. It already has issues and at most bringing back to stock might help alleviate some of the issues that the tune could be causing.

karl18d

Thanks... I didn't know the bit about the Flashpaq... definitely good to know.

karl18d

So, I reset everything back to STOCK.

I started it up, hoping everything would magically fix itself... no such luck.

Codes:
P0652 - Sensor Reference Voltage 2 Circuit Low
P2127 - Accelerator Pedal Position Sensor 2 Circuit Low
P0340 - Camshaft Position Sensor Circuit

Dealership still can't fit me in until Monday... I guess that means I've got all weekend to try any forum generated fixes. I pray it's not the damn computer.

maldoro

Hey There,

Did you ever figure this out, I have a 2007 and getting some of the same codes that you were. I sent a PM

templer

If it was me I'd take your battery out and have them test it. Computers are so sensitive to low voltage. You could have a bad cell. Sounds like the computer and programmer ain't the problem. I put a ls2 in a 74 camaro. When i got it all wired I used the hei wire to supply power to the computer. Well when it would start that circuit would lose power and basically the car would go into limp mode. Found out from a friend I had to wire that into a relay. Did that and fixed my limp mode and iratic idle. Took few months to figure that out. That would be ez if you ask me to pull the battery and check it. How old is it? Or check the alternator.