KBarcellos
04-19-2006, 09:31 AM
I have a 95 540i Sport with 197k miles. Recently changed out both O2 sensors and cleared the fault code, but am getting a 1213 fault under very specific conditions:
1) Temperature is <45F.
2) Engine has been operating less than 3 minutes (assume O2 sensors have not yet kicked in).
3) Idling at the bottom of a fairly steep downward incline.
When those conditions are met the check engine light will come on briefly along with a very slight stumble to the idle. Revving the engine causes the CEL to go out, but the 1213 code is stored each time. Idle is good (much improved since replacing the 02 Sensors) and I have yet to get the CEL at any other time.
So far I have checked for vacum leaks, by spraying carb cleaner in at all of the likely failure points with the engine cold and the car pointed down the driveway but have been unable to pinpoint anything. I'm thinking that the fact that the fault occurs on the incline is some kind of clue, perhaps this is a fuel delivery problem and not a vacum problem or some combination of the two?
Any ideas where to look next?
1) Temperature is <45F.
2) Engine has been operating less than 3 minutes (assume O2 sensors have not yet kicked in).
3) Idling at the bottom of a fairly steep downward incline.
When those conditions are met the check engine light will come on briefly along with a very slight stumble to the idle. Revving the engine causes the CEL to go out, but the 1213 code is stored each time. Idle is good (much improved since replacing the 02 Sensors) and I have yet to get the CEL at any other time.
So far I have checked for vacum leaks, by spraying carb cleaner in at all of the likely failure points with the engine cold and the car pointed down the driveway but have been unable to pinpoint anything. I'm thinking that the fact that the fault occurs on the incline is some kind of clue, perhaps this is a fuel delivery problem and not a vacum problem or some combination of the two?
Any ideas where to look next?