please help 1222 problem

[dinggoo]

Hi everyone, before i start yes i did search and yes i did read many other posts about this problem but no luck

I have an 89 325i and it is throwing the 1222 code after the car has warmed up for about 5-10 min. And the idle waivers in-between 600-1000, once again after it has warmed up. The code is there when I'm driving for a bit with a constant RPM and goes away when i let off the gas, but not when i try to give it more gas. I have replace the coolant temp sensor, the O2 sensor, I had an exhaust leak at the triangular flanges before the O2 sensor but I fixed those, as far as i can tell there is no vacuum leaks. I also changed out MAF's and no such luck. I have a new fuel filter I'm gone put on but i doubt that has anything to do with it.

Im not sure why it is still doing it any help would be greatly appriciated

[jlevie]

The chances of an intake leak being the cause are excellent. Have a shop run a smoke test. There are other possibilities, but until intake leaks are ruled out by a smoke test there is no point in investigating anything else.

[dinggoo]

even though it only happens once it heats up? wouldn't an intake leak happen even if its cold?

[dnguyen1963]

even though it only happens once it heats up? wouldn't an intake leak happen even if its cold?

Rubber hose with small crack will expand once the engine heats up...hence vacuum leak.

[dinggoo]

Well I got a smoke test done and no vacuum leaks the shop ran a diagnostic and said it was the o2 sensor changed that, and no change. They said of not that its gone be the AFM so i guess finding one and checking that is next.

[paperplane94]

either too rich or too lean, hmmmmm.

What can cause that?

[dinggoo]

hey if i were to run a chip do you think it would solve the issue since it would dust be going to a different map

[dinggoo]

Anyone?

[EREKSHUN]

hey i am going through the same issue. i have a 89 325i and i also have code 1222 which kinda sucks because it can be various things.

so far i have replaced:
O2 sensor
fixed exhaust leak
took off cap but not rotor. no moisture at all.
Unplugged ECU
Reset ECU

My car actually ran awesome after i reset the ECU. you should try it. Unplug your battery for a hour or so. I ran it for over a hour last night and a most of today but tonight it started back up. I'm backfiring around 3000 RPMs. Reason i thought it was the MAF is because it almost only happens when i am at full throttle. wrong air fuel mix i presume. i wanted to replace my MAF but i see it had no luck with you.

[bastianshaw]

my money is on too lean from an intake leak considering it is only happening in closed loop w high manifold vacuum(on throttle)