possible pcm failure or Temp Sensor
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TECH Apprentice
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Joined: Aug 2015
Posts: 388
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From: Charlotte NC
possible pcm failure or Temp Sensor Little background,
02 Trans Am mostly stock with the exception of Diablo Predator 120k miles
Headers installed about three weeks ago, broke the coolant sensor and replaced with new sensor from advance.
Car had been running great with the exception of an exhaust leak. The CE light came on revealing codes via a predator Diablo.
p0118 p1115
Did some research found where some had issues with the wire connector itself related to the P0118, so I soldered in a new cleared the code and went for a drive to the exhaust shop to get the leak fixed.
Welded the exhaust leak up and drove around for about 10 miles with no problems.
The next day my wife and I went to dinner and on the way home, the temp gauge began bouncing and the car became to buck and surge. Each time I'm guessing it was going from open to closed as I could hear the fans coming on. Finally the gauge went to the very bottom of its travel and stayed.
Got the car home and pulled the codes and found P0118 again also noticing the alt gauge was reading around 15v while the battery was showing 13v while the car was running.
I ordered an alternator and Delco coolant sensor.
While waiting a few days for the parts to arrive I removed the pcm connectors and plugged everything back in tightening the 7mm bolts to the correct torque.
Parts came today so I installed the alt and coolant sensor, cranked the car and same thing temp gauge bouncing fans cycling on and off very quickly.
Plugged in the predator to log and watch predator says cannot communicate with the vehicle.
Tried pulling codes same message codes cannot be displayed.
Any Ideas and help certainly appreciated before I go throwing parts at it.
02 Trans Am mostly stock with the exception of Diablo Predator 120k miles
Headers installed about three weeks ago, broke the coolant sensor and replaced with new sensor from advance.
Car had been running great with the exception of an exhaust leak. The CE light came on revealing codes via a predator Diablo.
p0118 p1115
Did some research found where some had issues with the wire connector itself related to the P0118, so I soldered in a new cleared the code and went for a drive to the exhaust shop to get the leak fixed.
Welded the exhaust leak up and drove around for about 10 miles with no problems.
The next day my wife and I went to dinner and on the way home, the temp gauge began bouncing and the car became to buck and surge. Each time I'm guessing it was going from open to closed as I could hear the fans coming on. Finally the gauge went to the very bottom of its travel and stayed.
Got the car home and pulled the codes and found P0118 again also noticing the alt gauge was reading around 15v while the battery was showing 13v while the car was running.
I ordered an alternator and Delco coolant sensor.
While waiting a few days for the parts to arrive I removed the pcm connectors and plugged everything back in tightening the 7mm bolts to the correct torque.
Parts came today so I installed the alt and coolant sensor, cranked the car and same thing temp gauge bouncing fans cycling on and off very quickly.
Plugged in the predator to log and watch predator says cannot communicate with the vehicle.
Tried pulling codes same message codes cannot be displayed.
Any Ideas and help certainly appreciated before I go throwing parts at it.
Thread Starter
TECH Apprentice
iTrader: (11)
Joined: Aug 2015
Posts: 388
Likes: 1
From: Charlotte NC
Got out my mac mentor fancy scanner and read the codes again now.
It is now showing p0117
The gauge will climb and about 30 seconds later drop to the lowest point. I can clear the code and the temp gauge will climb back up to 210 for about 30 secs and drop to its lowest point again.
Data logging shows a constant 284 degrees.
I'm stumped any info on such?
It is now showing p0117
The gauge will climb and about 30 seconds later drop to the lowest point. I can clear the code and the temp gauge will climb back up to 210 for about 30 secs and drop to its lowest point again.
Data logging shows a constant 284 degrees.
I'm stumped any info on such?
Thread Starter
TECH Apprentice
iTrader: (11)
Joined: Aug 2015
Posts: 388
Likes: 1
From: Charlotte NC
Just wanted to provide another update as I may have the problem resolved.
Ok let me step through the failure modes and root causes.
1. Broken ECT sensor (during header install car would not crank)
2. Replaced the sensor with BDW brand from advance auto (Code P0118 & P1115 sensor failed within 1 week)
3. Soldered in a new 2 wire connector without verifying the original as bad thinking this was the problem and not the BDW sensor. Read many threads that talked about the connector causing problems. (Yellow wire had a cold solder joint verified through ohm meter which was isolated between the joint and connector pin)
4. Replaced the BDW sensor with AC Delco ( DTC set P0117 and P12?? = Low coolant which adds fuel as safety)
5a. Removed solder connections and cut wire back, soldered new joints on both wires verified continuity through ohm meter. 5b. Added coolant to radiator and cranked car allowing thermostat to open and air pocket release due to coolant loss after removing two ECT sensors. (No DTC set, temp gauge reading as normal again)
I'm usually good about not introducing multiple variables when trying to solve a problem. That said I read too much and changed two things without verifying one as being faulty.
Hope this helps someone in the future.
My diablosport predator is still saying it cannot communicate with the vehicle....... strange. Time to upgarde to HP Tuners Pro
Ok let me step through the failure modes and root causes.
1. Broken ECT sensor (during header install car would not crank)
2. Replaced the sensor with BDW brand from advance auto (Code P0118 & P1115 sensor failed within 1 week)
3. Soldered in a new 2 wire connector without verifying the original as bad thinking this was the problem and not the BDW sensor. Read many threads that talked about the connector causing problems. (Yellow wire had a cold solder joint verified through ohm meter which was isolated between the joint and connector pin)
4. Replaced the BDW sensor with AC Delco ( DTC set P0117 and P12?? = Low coolant which adds fuel as safety)
5a. Removed solder connections and cut wire back, soldered new joints on both wires verified continuity through ohm meter. 5b. Added coolant to radiator and cranked car allowing thermostat to open and air pocket release due to coolant loss after removing two ECT sensors. (No DTC set, temp gauge reading as normal again)
I'm usually good about not introducing multiple variables when trying to solve a problem. That said I read too much and changed two things without verifying one as being faulty.
Hope this helps someone in the future.
My diablosport predator is still saying it cannot communicate with the vehicle....... strange. Time to upgarde to HP Tuners Pro
mine is doing the bs with it going from normal 178 to 284 when im driving. I replaced the sensor and took it for a ride and it was fine . Way back from the store same bs it kicks the check gauges light .
bring it home unplih sensor pullback some tape and connector looks good . Had car running and unpligged it , aeroforce shows 46580 i plug it back in 140 where the temp was , i wiggled the connector and tugged wire and aerofoce stayed at 140. Wtf could it be . sensor is gm from rockauto . I mean possibly the connector ? What should i check with my volt meter? had a code p0117
bring it home unplih sensor pullback some tape and connector looks good . Had car running and unpligged it , aeroforce shows 46580 i plug it back in 140 where the temp was , i wiggled the connector and tugged wire and aerofoce stayed at 140. Wtf could it be . sensor is gm from rockauto . I mean possibly the connector ? What should i check with my volt meter? had a code p0117
