"Service" and "Service Engine Soon" lights are on. No codes (DTC) are coming up. Engine runs great, shifts great, only the tach (will fall to "0" for a second then return to correct RPM) suggests a problem. Two GM dealers took my money and fixed nothing. What's causing the lights to stay on? Thanks
have the same problem?
Sunday, November 11th, 2012 AT 10:08 PM