How to clean MAF on 90 535

[wjbell]

Hey guys, long time no post...

I'm trying to smooth out the idle on my 535. I read about increasing the spark plug gap. The stock is .028 and it suggests .034-.036. I put my stock Bosch's at .032. Don't know if that helped at all but...

I also read a thread here that someone cleaned their MAF and it improved their idle. Does anyone know if that helps? Is there detailed instructions how to clean it? Do you need to remove it? Oh, one other thing... where is the MAF

TIA

[BigKriss]

535i doesn't have a MAF, it has a AFM.

[Rus]

I cleaned the AFM on my 535 as well as readjusted the position of the circuitry inside (to move the contact path to a fresh strip of copper). Cleaning is relatively easy. I used carb cleaner and basically just wiped off any carbon build up inside. The door should swing around freely. I can't say if it helped or not since as it turned out, the engine had far greater issues than metering air flow. Considering the ease of cleaning, I'd go ahead and clean it. Have a look at your ICV as well. That valve can have a big impact on idle. HTH

[BigKriss]

How do you clean the ICV? I have mine removed at the moment.

I cleaned the AFM on my 535 as well as readjusted the position of the circuitry inside (to move the contact path to a fresh strip of copper). Cleaning is relatively easy. I used carb cleaner and basically just wiped off any carbon build up inside. The door should swing around freely. I can't say if it helped or not since as it turned out, the engine had far greater issues than metering air flow. Considering the ease of cleaning, I'd go ahead and clean it. Have a look at your ICV as well. That valve can have a big impact on idle. HTH

[Rus]

How do you clean the ICV? I have mine removed at the moment.

All I did to clean that ICV was spray carb cleaner in the valve and swing the gate around (effectively making sure it was operating smoothly). Try to avoid getting carb cleaner into the electrical part of the valve. Overall the objective is to remove carbon deposits and make sure the valve operates smoothly and freely. HTH

[wjbell]

Ok, thanks guys. I'm guessing this is my AFM:

http://www.realoem.com/bmw/showparts...67&hg=13&fg=15

Is the AFM hard to remove? Is it fairly self-explanatory with regard to adjusting it to a clean part of the contact and cleaning it? The ICV seems pretty simple, I'm just unsure of the AFM and don't want to screw it up and turn a running car with a rough idle into a non-running car.

Thanks for the responses.

[javoresku]

Is the AFM hard to remove?

It's simple -
1.disconnect cable plud (pos 20)
2. unscrew the clapms(pos 9 &15) and remove hoses (8 &14) to the air filter box and to the trottle body,
3. unbolt the bracket(3)
4. Pull.

OT: on that pic it says "ENDED" for the AFM and it's replaced by a
"RMFD MASS AIR FLOW SENSOR" - interesting...

[BillionPa]

they dont make the AFM anymore, as the MAF is far superior and plug and play.

[javoresku]

they dont make the AFM anymore, as the MAF is far superior and plug and play.

I didn't know there is a P&P MAF for the M30 - that is what I find interesting. I'll have to do some more research on that.

[BillionPa]

well, its as close to plug and play as you can get, ECU reprogramming may be required

its the same part for all M30 engines, even E20 series.

if you really want a kick out of the M30, megasquirt + MAF + 1 coil per plug (or 2 with wasted spark)

turbo or not, you will have a lot more control over the engine with less restriction and moving parts.