New to me Z06: Already having issues, OBDII related
 

Hey guys,

Have not been in the corvette world for last few years and couldn't resist getting into a 2015 Z06. Love the car so far, 2012 CTS V is no comparison for driving experience.

Now, onto my issue: First 300 miles was perfect, put 93 octane costco fuel in tank and 10 miles later im getting a check engine light but no other messages. I was not too concerned as i figured it might be fuel related. The light would vanish after a few restarts but then reappear a few miles down the road. I have since put half a tank of chevron fuel in but light has not disappeared.

The real issue Im having now is with my Actron OBDII code reader. I wanted to verify what error code was present for peace of mind, but am having other issues with getting the code reader to read anything. I have tried multiple times with key on engine off, key on engine on, service mode and every thing in between. Reader states operating error in every combination. When reader is plugged in in acc mode or with engine running, every service light on the DIC lights and I get service power steering and service rear axle messages. All messages and lights disappear as soon as code reader is unplugged. This worries me a bit as it makes me think I have some other electrical issue. I did plug in the reader to a Jeep to insure that the problem was not with reader and all worked well.

Any ideas? Im about ready to take to dealer but would like to avoid that if i can.

Thank,
Bryan

Try asking your local auto parts store to connect. There may be some compatibility issue between your car and your code reader.

Just a quick (free) check to confirm your car has the problem.

Ron

Are you still on the original battery?
I had similar symptoms (could not read from OBD port) and some of the same messages when my car would sit too many weeks off the battery maintainer.
Charging it up usually solved the problem until it would sit for long periods again.
I just recently changed to a new battery since mine was approaching 3 years old.

You might start there since this is easy to check.

I'm also banking on it being the scanner. I had the same problem when I tried to make my scanner (only updated to 2015) talk to my 2018 jeep. If your scanner has the ability, try reading it as a generic obd

Poke around under the dash and make sure the previous owner didn't install any equipment that taps into the data lines. That could be messing up communication between your PCM and scan tool. If your scan tool is less than a decade old it should do basic diagnostics on a 2015 with no problems.

For the code - make sure your MAF is clean and there is no oil in the intake system. Mine threw a code, found lots of oil in intake and had to replace the air filter.

good luck.

Battery voltage is 12.44 volts which should indicate about 70% SOC, also checked voltage at the pins of the OBD port. My scanner is is a cheap autozone scanner and is at least 5 6 years old and has not been updated since new.

I have looked over most of the wiring under dash and do not see where anything had been installed.

Rather than let let autozone mess with it Ive got a new bluetooth scanner ordered, was probably time for a new one anyway. Hopefully I can read the code with the new one and dont have other problems. Will update once I get the new scanner.

Thanks for the feedback guys.

Your 1st mistake.......

Costco fuel is Top Tier, what is the issue? I have been using it for 15+ years with no issues.

Have you verified the car is 100% bone stock?

Got my Lemur Bluedriver scanner today and solved all the connection issues. No DIC messages and reads perfect. Is a much better scanner that the cheap wired ones from the auto parts stores. I highly recommend it if anyone is looking to buy a code reader.

One code was pending and is P080C ( Upshift/Skip shift solenoid control circuit low). So now the question is wether its the connector, the actual solenoid, or is there already a skip shift eliminator previously installed that is acting up.

I have noticed the skip shift 1-4 message appearing on dash but I have not noticed it locking me out of 2nd gear at all. I just contributed this to speeding up in first before shifting, but obvioulsy something is going on here. Will be jacking up and looking at wiring tomorrow.

Anyone know what exactly what voltage parameters would indicate the "low" reading? Would this indicate that its always engaged or not engaging? My logic tells me it would be engaged or shorted as the solenoid would be active.

Thanks,
Bryan

Thanks for the input, until I read this I was convinced it was NOT my scanner and was ready to take to dealer.

:iagree:

Costco has been Top Tier for a couple of years or more, and I've seen no reports of problems except too many cars there. I'm told that in our area their gas is from Shell.

Costco Regular is about 15 cents/gallon cheaper than the majors, nice but no big deal.
Costco Premium is about 75 cents/gallon cheaper than the majors, that's a lot.
:thumbs:

I can't address your whole issue, but even with the skip-shift eliminator installed and working, you will still get the message in the DIC. That is normal.

Updated, problem found.
 

Lifted it this morning to check out the CAGS wiring and solenoid to discover it lying against the exhaust. Last picture was moved slightly to photo the damage. As I was suspecting it had a CAGS eliminator already installed but was not tie-wrapped properly and burned. I measured the resistance and got 38 ohms. Anyone know what they should measure?

Thankfully the OEM connector and wiring was not damaged too badly and just reconnected as it should be. Hopefully this was the issue and do not get anymore CEL's. I don't believe the skip shift will bother me too much as I leave in first gear until above 20mph anyway. If it does I will be ordering a new one.

https://cimg5.ibsrv.net/gimg/www.cor...7b9a6a8166.jpg
https://cimg4.ibsrv.net/gimg/www.cor...0513a40aaa.jpg
https://cimg2.ibsrv.net/gimg/www.cor...c8ef8ce4bc.jpg

As long as you shift at 20 mph or higher or below 15 mph you shouldn't be bothered. Skip shift usually rears its head in very slow traffic where cars aren't accelerating very fast away from a stop. Any even slightly aggressive use of throttle will turn off CAGS as well if you happen to shift between those two speeds.

Bill