2005 Yukon Denali stalling problem P0300 code

[HammerMMI]

Started out as an intermittent stalling problem when letting off the throttle at highway speeds. Happened several times before posting a P0300, P0171 & P0174 codes.
Would restart and run fine for the duration of the trip. Then it started happening in stop and go traffic and highway about every half a mile. Replaced MAF sensor, problem seemed to clear for almost a year, then returned. Replaced MAF sensor again but did not fix.
Replaced Bank 1 upstream and downstream O2 sensors and seem to idle and respond to throttle better. I test drove for about 70 miles with no problems. I will update after a 1000 mile return to Texas from Colorado.

 

[Fless]

A misfire code like P300 can be caused by an out-of-sync or defective crankshaft position sensor. Consider having a CKP sensor relearn done with a capable scanner, just to rule it out. The relearn is recommended anytime a CKP sensor is changed or suspected to be faulty.

 

[HammerMMI]

A misfire code like P300 can be caused by an out-of-sync or defective crankshaft position sensor. Consider having a CKP sensor relearn done with a capable scanner, just to rule it out. The relearn is recommended anytime a CKP sensor is changed or suspected to be faulty.

Thanks for the tip. If the problem happens again I’ll do what you suggest.