Ok well i hooked my car up to the scanner today and im getting 2 codes. a P0400(egr) which i know is bad...and a P1661: Mfg. Defined Computer and Auxiliary Output Code. I have no idea wtf this is. Could it be from unplugging the light? Also...Those are the only 2 codes on my computer and the car seems to skip at the same exact rpm in every gear..seems to be right at 1900rpms. Now the car is a heads/cam car. I just replaced a faulty o2 sensor thinking that was it. When i replaced the o2 sensor the sensor code didnt come back and neither did a MAF code(which is a good thing)...so why is my car still misfiring? i dont get it....and I have no clue wtf that P1661 code is. Anyone have any ideas?-Mark

 

P1661 has something to do with the quad driver module/output device module. Other than that, I can't tell you anything. I'm sure there are others on here who will chime in.

 

wtf does that mean...lol..you think it could be from unplugging the bulb?

 

"Quad driver...." where do people get all this faulty code info. Go to Shoebox's page, and check the code list specifically for LT1 F-Bodys.

http://shbox.com/1/Dtcs.htm

P1661 = Malfunction Indicator Lamp (MIL) control circuit

Hmmmmm.... do you think that cold be from unplugging the bulb?

 

Do I feel silly. Went back and looked the code up, and right there in bold type it says MIL Circuit Fault. Didn't even see that. The quad driver is part of the way to solve the fault when you don't know what's causing it. In this case it is obvious. BTW, this info comes out of an OBDII manual I have, which reproduces a lot of the GM tech info. I just should have looked closer at the definition.