Anyone else think CEL 1222 is way to broad?

[B-well]

I've been having a problem with a bad running m42.

It's been doing some random sputtering/bucking under load, under 2k rpms and only when up to temperature

Of corse a CEL popped up and its 1222, which in my opinion is just bmw's way of saying "hey something is wrong, fix it"

has anyone else had a problem similar to mine?

one time i had gone through a puddle in an intersection and experienced a similar bucking, although at all rpms and would barely make it to 2500, from a splashed air-filter/afm but that went away within 2 miutes.

[jlevie]

Nine times out of ten a 1222 (Lambda) fault will be caused by intake leaks, an aged O2 sensor, or a combination of those. The O2 sensor is a scheduled maintenance item with a replacement interval of 100k. Replace the O2 sensor unless it is new, have a smoke test run, and fix the leaks the test turns up. There are other possibilities, but until those have been dealt with it is pointless to look further.

[B-well]

Nine times out of ten a 1222 (Lambda) fault will be caused by intake leaks, an aged O2 sensor, or a combination of those. The O2 sensor is a scheduled maintenance item with a replacement interval of 100k. Replace the O2 sensor unless it is new, have a smoke test run, and fix the leaks the test turns up. There are other possibilities, but until those have been dealt with it is pointless to look further.

i appreciate the fast response.

Car has 99k so it hits the o2 mark right on the head.

[B-well]

replaced o2 sensor

added fuel system cleaner and 10 gallons of gas.

took a somewhat frayed end off of a hose

sprayed carb cleaner on hoses and other areas where vacuum leaks could occur but no change in idle.

Car runs better, reduced the frequency of bucking by 80 percent but it still occurs sometimes in the same situations.

[jlevie]

Have a smoke test run. If it is done correctly the exhaust will be plugged and an adapter will be substituted for the AFM. Then a smoke pressure of at least 2psi will be held for several minutes. Smoke will then migrate to a leak where ever it is and make the leak visible.