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jazzmaster, ASE Certified Technician
Category: Pontiac
Satisfied Customers: 2951
Experience:  ase certified
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1998 Sunfire: sputters..about 2.5 hours of driving, (in hotter weather

Customer Question

1998 Sunfire sputters after about 2.5 hours of driving, (in hotter weather, I think) the car would sputter and go out. Now it already is after 1/2 hour of driving. Can start right after and go again. Starting/cranking is usually a bit longer than normal.
Submitted: 6 years ago.
Category: Pontiac
Expert:  jazzmaster replied 6 years ago.
hi, did you get this checked with a scanner connected to it and if so did you get any engine codes?I am thinking that there maybe a problem with either the throttle sensor or the coolant(for the pcm) sensor that maybe inhibiting the fuel delivery process./is this running hotter than usual and are there any other symptoms that you can think of ,how long does it take to start after it sputters and or stalls (if it does stall at all)
Customer: replied 6 years ago.
Yes, had a scanner on it. It showed it was running rich and also running lean.
The temperature is normal when it happens.
It cranks about 6-7 seconds for starting cold or hot.
It usually starts pretty much right after it goes out. It sometimes sputters a bit after.
Expert:  jazzmaster replied 6 years ago.

ok,I ned you to do this relearn listed below before we can go further,so do this and let me know if that helped ,,,,


IMPORTANT: A Crankshaft Position System Variation Learning Procedure must be performed any time a change is made to the crankshaft sensor to crankshaft relationship. Changing the crank sensor to crankshaft relationship will not allow the PCM to detect misfire at all speeds and loads accurately. Resulting in a possible false misfire DTC being set. Removing a part for inspection and then reinstalling the same part is considered a disturbance. A false DTC P0300 could be set if this procedure is not performed.

The learn procedure is required after the following service procedures have been performed, regardless of whether or not DTC P1336 is set:

  • PCM replacement.
  • Engine replacement.
  • Crankshaft replacement.
  • Crankshaft position sensor replacement.
  • Any engine repair(s) which disturbs the crankshaft/harmonic balancer to the crankshaft position sensor relationship.

CAUTION: Before performing the Crankshaft Position System Variation Learning Procedure always set the vehicle parking brake and block the drive wheels in order to prevent personal injury. Release the throttle immediately when the engine starts to decelerate in order to eliminate over revving the engine. Once the learn procedure is completed, the control module will return engine control to the operator and the engine will respond to the throttle position.

IMPORTANT: The battery must be fully charged and in good condition. The scan tool connection at the DLC is clean and tight before starting the Crankshaft Position System Variation Learning Procedure.

  1. Close the hood.
  2. Block the drive wheels and set the vehicle parking brake.
  3. Put the vehicle in Park or Neutral.
  4. Turn all the accessories OFF.
  5. Install a scan tool.
  6. Start and run the engine until it is at normal operating temperature 85°C (185°F).
  7. With the engine still running, enable the Crankshaft Position System Variation Learning Procedure with the scan tool.
  8. Press and hold the brake pedal firmly and raise the engine speed to the specified value, RELEASING the throttle as soon as the engine cuts out.
  9. Verify with the scan tool that the crankshaft variation has been learned. Perform this procedure up to 10 times. If the PCM will not learn the variation, a DTC P1336 should be set. Refer to the DTC P1336 Crankshaft Position (CKP) System Variation Not Learned 2.4L or the DTC P1336 Crankshaft Position (CKP) System Variation Not Learned 2.2L for diagnosis.


also there could be a problem with the air flow meter ,you can try and clean the sensor by spraying it with carb cleaner and using shop air ,blow it dry then reinstall it ,this may be the problem as dirt will often get on the resistor wire(s) in the sensor ...guy...