C4 quad driver, car dies, will not start = help
03-15-2011, 11:23 PM
#1
Intermediate
Thread Starter
Member Since: Jan 2010
Location: San Diego Ca
Posts: 27
Likes: 0
Received 0 Likes
on
0 Posts
C4 quad driver, car dies, will not start = help
C4 quad driver, car dies, will not start = help
O.K. Last time I posted it was prior to the check engine light coming on. Now, the check engine light comes on. I lost my Vette mechanic, and have a real good guy working on it now I've known for years but he is having a hard time with this.
Heres the deal:
Now the check engine light comes on....
I've replaced the fuel filter and a couple fuel lines that were damaged or old.
The Quad Driver code comes on now.
My car dies without warning, in intersections and at whim. Will not restart right away, but seems to re start when it feels like it and wants to.
This last time it died today, it reved a little higher than normal, than puttered out.
The battery dies quickly it appeared, unlike before during this bout.
this has been happening for about a month for the dying out but like once a week, now it's been twice this week.
The check engine light just came on last week.
My mechanic seems to think he should replace the ecm, however i've read everything from fuses to individual modules that could be the cause of it all, setting the light, the dying?
Help
O.K. Last time I posted it was prior to the check engine light coming on. Now, the check engine light comes on. I lost my Vette mechanic, and have a real good guy working on it now I've known for years but he is having a hard time with this.
Heres the deal:
Now the check engine light comes on....
I've replaced the fuel filter and a couple fuel lines that were damaged or old.
The Quad Driver code comes on now.
My car dies without warning, in intersections and at whim. Will not restart right away, but seems to re start when it feels like it and wants to.
This last time it died today, it reved a little higher than normal, than puttered out.
The battery dies quickly it appeared, unlike before during this bout.
this has been happening for about a month for the dying out but like once a week, now it's been twice this week.
The check engine light just came on last week.
My mechanic seems to think he should replace the ecm, however i've read everything from fuses to individual modules that could be the cause of it all, setting the light, the dying?
Help
03-16-2011, 04:44 AM
#2
You will always get better response if you remember to list the year of your car when posting. Assuming this is the 93 in your profile, more information is needed.
There are three quad driver circuits and three separate DTC's so you need to know which one is being set.
The quad driver circuits control the A/C clutch, cooling fans, torque converter lock up or skip shift relay depending on transmission, and also the EGR, EVAP purge and AIR injection pump relays.
It is possible the purge solenoid, EGR or locked TCC could cause your stalling problem, and since the quad drivers are in the ECM , your current mechanic may be on to something. The ECM for a 93 can be very difficult to find so hopefully it is something less serious.
My first diagnostic step would be to identify the exact QDM code then use the step by step troubleshooting procedure in the Factory Service Manual for that code. If your mechanic does not have a copy make sure he gets one, it is always the best guide to sorting out such problems, good luck.
There are three quad driver circuits and three separate DTC's so you need to know which one is being set.
The quad driver circuits control the A/C clutch, cooling fans, torque converter lock up or skip shift relay depending on transmission, and also the EGR, EVAP purge and AIR injection pump relays.
It is possible the purge solenoid, EGR or locked TCC could cause your stalling problem, and since the quad drivers are in the ECM , your current mechanic may be on to something. The ECM for a 93 can be very difficult to find so hopefully it is something less serious.
My first diagnostic step would be to identify the exact QDM code then use the step by step troubleshooting procedure in the Factory Service Manual for that code. If your mechanic does not have a copy make sure he gets one, it is always the best guide to sorting out such problems, good luck.
Last edited by toptechx6; 03-16-2011 at 05:02 AM.
03-16-2011, 12:09 PM
#4
Since the FSM can be intimidating I'll mention that the troubleshooting procedure for the quad driver circuits starts on page 6E3-A-56 of book number two.
03-25-2011, 01:11 AM
#6
Intermediate
Thread Starter
Member Since: Jan 2010
Location: San Diego Ca
Posts: 27
Likes: 0
Received 0 Likes
on
0 Posts
[B]Here is a full update of the repair. Im on the road again!!![/B]
OK, Car is running like a dream. 
Symptoms that carried on forever it seemed.
* CAR DIED RANDOMLY. FIRST APPEARED TO BE ON HILLS, BUT THEN IT JUST STARTED HAPPENING WHENEVER AND WHEREVER
* WHEN CAR WAS IDLING, THE NEEDLE DID NOT STAY STEADY
* A FEW TIMES MY RPMS RAGED WHILE DRIVING CAUSING ME TO THROW IT INTO NEUTRAL, PULL OVER, SHUT OFF AND RESTART MY CAR (AUTOMATIC)
* CAR SEEMED TO BE DRAGGING BRICKS WHEN STEPPING ON IT
* PERIODICALLY IT HAD A CUTTING OUT KIND OF THING WHEN LAID INTO THE PEDAL, I'D LET OFF THE GAS AND IT SEEMED FINE. WE THOUGHT IT MIGHT BE SPARK PLUGS
* A FEW TIMES WHEN IT DIED I WAS ABLE TO RESTART IT, SO WE INITIALLY THOUGHT IT WAS FUEL RELATED TOO, THERE WERE NO CODES
* TOWARDS THE END, AND ONLY HAPPENED A COUPLE TIMES, ACTED LIKE IT WAS BOGGING DOWN, FILLING UP WITH FUEL, SPITTING, AND ONCE BACKFIRED
* A FEW TIMES IT DID NOT WANT TO START, BUT AFTER TRYING TO START IT FOR A WHILE IT WOULD START, SO AGAIN, WE THOUGHT IT WAS FUEL RELATED
* AT THE END OF ALL THIS, THE QUAD 4 CODE AROSE, FINALLY, THEN THE CAR DIED AND I WAS DONE = IT WENT TO THE DOCTOR
DIAGNOSIS, ANSWER, WHAT WE DID.
* REPLACED THE FUEL FILTER, THOUGHT IT HELPED BUT THE CAR WAS JUST MESSING WITH ME
* THEN QUAD 4 CODE LED TO DISTRIBUTOR
* CHECKED ALL FUSES, A OK
* REPLACED DISTRIBUTOR, WATER PUMP, PLUGS, WIRES, AND THERMOSTAT
NICE $$$$$$ JOB.
CAR RUNS LIKE A DREAM, BETTER THAN HAS IN SO LONG. SO FAR I CAN TELL THERE IS NO HESITATION, RESPONSIVE AGAIN, AND IS A DREAM, DREAM DREAM.
I LOVE MY CAR AGAIN......
SHE GOT A BATH AND WE DROVE FOR PROBABLY 3 HOURS BECAUSE I DIDN'T HAVE HER FOR OVER A WEEK. DIDN'T WANT TO COME HOME BUT NEEDED GAS....
I HOPE THIS HELPS SOMEONE OUT THERE THAT MAY HAVE SIMILAR SYMPTOMS.
Sorry about the formatting, cut and paste job, its late, I'm tired
Thanks to all for your input..
Symptoms that carried on forever it seemed.
* CAR DIED RANDOMLY. FIRST APPEARED TO BE ON HILLS, BUT THEN IT JUST STARTED HAPPENING WHENEVER AND WHEREVER
* WHEN CAR WAS IDLING, THE NEEDLE DID NOT STAY STEADY
* A FEW TIMES MY RPMS RAGED WHILE DRIVING CAUSING ME TO THROW IT INTO NEUTRAL, PULL OVER, SHUT OFF AND RESTART MY CAR (AUTOMATIC)
* CAR SEEMED TO BE DRAGGING BRICKS WHEN STEPPING ON IT
* PERIODICALLY IT HAD A CUTTING OUT KIND OF THING WHEN LAID INTO THE PEDAL, I'D LET OFF THE GAS AND IT SEEMED FINE. WE THOUGHT IT MIGHT BE SPARK PLUGS
* A FEW TIMES WHEN IT DIED I WAS ABLE TO RESTART IT, SO WE INITIALLY THOUGHT IT WAS FUEL RELATED TOO, THERE WERE NO CODES
* TOWARDS THE END, AND ONLY HAPPENED A COUPLE TIMES, ACTED LIKE IT WAS BOGGING DOWN, FILLING UP WITH FUEL, SPITTING, AND ONCE BACKFIRED
* A FEW TIMES IT DID NOT WANT TO START, BUT AFTER TRYING TO START IT FOR A WHILE IT WOULD START, SO AGAIN, WE THOUGHT IT WAS FUEL RELATED
* AT THE END OF ALL THIS, THE QUAD 4 CODE AROSE, FINALLY, THEN THE CAR DIED AND I WAS DONE = IT WENT TO THE DOCTOR
DIAGNOSIS, ANSWER, WHAT WE DID.
* REPLACED THE FUEL FILTER, THOUGHT IT HELPED BUT THE CAR WAS JUST MESSING WITH ME
* THEN QUAD 4 CODE LED TO DISTRIBUTOR
* CHECKED ALL FUSES, A OK
* REPLACED DISTRIBUTOR, WATER PUMP, PLUGS, WIRES, AND THERMOSTAT
NICE $$$$$$ JOB.
CAR RUNS LIKE A DREAM, BETTER THAN HAS IN SO LONG. SO FAR I CAN TELL THERE IS NO HESITATION, RESPONSIVE AGAIN, AND IS A DREAM, DREAM DREAM.
I LOVE MY CAR AGAIN......
SHE GOT A BATH AND WE DROVE FOR PROBABLY 3 HOURS BECAUSE I DIDN'T HAVE HER FOR OVER A WEEK. DIDN'T WANT TO COME HOME BUT NEEDED GAS....
I HOPE THIS HELPS SOMEONE OUT THERE THAT MAY HAVE SIMILAR SYMPTOMS.
Sorry about the formatting, cut and paste job, its late, I'm tired
Thanks to all for your input..
