Pontiac Repair: 97 GRAND PRIX, exhaust gasket, correct voltage

Question
QUESTION: I HAVE A 1997 GRAND PRIX 2 DOOR COUPE 3.8 SUPERCHARGER. JUST PUT COIL PACKS, PLUGS AND WIRES FOR THE P0303 I GOT A WHILE BACK. ALSO JUST DID EXHAUST MANIFOLD GASKET, TSTAT AND SENSOR FOR LOW COOLANT LIGHT. NOW, LESS THEN 100 MILES LATER GOT A P1655. I AM A WRITER AT HONDA. THE USED CAR GUY SAYS IT IS RELATED TO QUAD 4 MODULE CIRCUIT. DO YOU HAVE ANY INFO PLEASE ?

ANSWER: Hi Suzzanne:

Quad driver codes are a difficult code to diagnose. basically what it means is one of the solenoids or relays or something that the ECM is controlling to turn on it not working the way it should. A quad driver is basically an internal switch that's also a circuit breaker in a way. if one of the solenoids is shorted to ground the code sets and the computer shut's down that driver before it causes internal damage to the computer. It works the other way as well is something was left unplugged and the computer doesn't see the correct voltage on a circuit before it trys to turn something on it will set that code as well. I was just looking around for a 97 service manual and can't find one out on line service information only goes bad  to the 98 model year and that 1655 code is not a code for a 98 model year. All I can basically tell you is to make sure that nothing "wire harness" were pinched or routed the wrong way where they may have melted on a manifold. make sure everything is plugged back in all the solenoids including the one for the evap solenoid and boost valve for the supercharger. If you don't find anything obvious which I bet it is something like that send me a follow up question and I'll see If I can't hunt down a book and see exactly what is on that quad #4 driver. Good luck :)


---------- FOLLOW-UP ----------

QUESTION: I THINK I EMAILED TO THE WRONG PLACE JUST NOW. FOLLOW UP IS SHOULD I GO TO THE DEALER WHO DID THE INTAKE GASKET (EXHAUST GASKET ?) FOR THE COOLANT STUFF (RO IS AT HOME TEN HOUR JOB)OR THE GUY WHO DID THE COIL PACKS ? ALSO I WAS REAR ENDED 40 MPH 3 MONTHS AGO, DROVE FOR 2 BEFORE FIXING, THIS IS THE FIRST TIME I HAD A PROBLEM LIKE THIS CODE, COULD IT BE A PINCHED WIRE JUST NOW CAUSING A PROBLEM ? THANK YOU AGAIN SO MUCH.

Answer
Well, It's a tough call. What was done last and how long inbetween repairs. I'm not saying it was caused by a repair because I get that all day long at work "ever since You did......" But if you had no issue inbetween repairs and ther was more than a few hundered moles inbetween and no issue and now after the last repair this cropped up it could verry well be self inflicted problem or something off the beaten path. My gut feeling is something was left unplugged. Af for a problem from an accident it more than likely would have cropped up well before this but you never know. Let me know how you made out. I'm off from work today and if you still have an issue with that code aske me a follow up again tomorrow and I'll round up that manaul if I can find it ......