Check engine light, no codes present???
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,087
Likes: 4
From: granville mass
Check engine light, no codes present???
I recently changed the exhaust on my 08 Z06 to the 2013 version, and got a M2W switch, which I've left in the open position. All pretty benign stuff.
After driving the car for about 30 miles I got a CEL. Plugged in my scanner, no faults read, tried to clear it, but didn't change.
Coincidence? Changed the A/F ratio enough for a lean code, but why wouldn't it show? Something with the M2W, which I hooked up the optional way that won't drain the battery?
After driving the car for about 30 miles I got a CEL. Plugged in my scanner, no faults read, tried to clear it, but didn't change.
Coincidence? Changed the A/F ratio enough for a lean code, but why wouldn't it show? Something with the M2W, which I hooked up the optional way that won't drain the battery?
Supporting Vendor
Joined: Feb 2011
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2024 C6 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (track prepared)
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For each code that can possibly get thrown, there are two settings - one that determines whether the check engine light will come on and the other that determine if a DTC code gets set. As such, it's possible for the CEL to come on but the scanner won't pick anything up.
Ultimately you're probably gonna need access to HP Tuners to figure this out.
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
One of two things is happening - either your OBDII scanner somehow isn't reading the ECM correctly or your tune's been modified.
For each code that can possibly get thrown, there are two settings - one that determines whether the check engine light will come on and the other that determine if a DTC code gets set. As such, it's possible for the CEL to come on but the scanner won't pick anything up.
Ultimately you're probably gonna need access to HP Tuners to figure this out.
For each code that can possibly get thrown, there are two settings - one that determines whether the check engine light will come on and the other that determine if a DTC code gets set. As such, it's possible for the CEL to come on but the scanner won't pick anything up.
Ultimately you're probably gonna need access to HP Tuners to figure this out.
