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duckloads
03-07-2005, 06:06 PM
I'm getting the 1222 engine code and have read all the threads on this generic malfunction. Is it possible or recommended to clean the MAF with throttle body or carb cleaner?

Thanks
1991 535im

Mobius
03-07-2005, 07:50 PM
If your car is stock, you don't have a MAF, you have a much more primitive AFM. You can clean it if you want, but you'd be the first person I've heard of who had a dirty AFM.

If you're getting a 1222, you're probably getting it only at idle (right?) - it's 100% more likely that you have a vacuum leak. Check the hose to your brake booster and the check valve. There's a small nipple on the underside of the check valve that breaks off and causes the engine to lose vacuum. Also, the hoses themselves become very brittle and may crack excessively along the underside. That hose and check valve alone cured my 1222.

duckloads
03-07-2005, 08:13 PM
Thanks for the reply. The items you mention appear original and very brittle, but otherwise intact. I'll replace them. The check engine light comes on at idle and at slow speeds just after the engine starts to run like crap. I can quickly turn the ignition off and back on, then it runs right again. That engine never has idled worth a flip. Thanks again,

shogun
03-07-2005, 08:15 PM
Battery and charging voltage is also to be checked:
Find a digital multimeter and stick the probe into the cigarette lighter socket in the center console.

The following are the detail figures I use for my own evaluation:
With key out of ignition switch, should see 12.4V or above. 12.0 V is getting low.
With key inserted and turned to position 2 (don't start car), should see 12.0V or more. 11.6V would be too low.
Crank car, catch the lowest voltage reading during that couple of seconds. Should see 10.0V or above. 9.5V would be marginal.
The above just consider the health of battery itself.
Car running at 1500 RPM or more, should see 13.7 to 14.3V, 13.6V or below means the charging system is weak.