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nariusb
03-25-2006, 12:42 PM
Can you, please help me.
How do I test throtle switch on my automatic, m20 525i? I believe it's udjustable also, how do I udjust it?
The reason is my idle is about 900 and should be at 700. I read that the switch udjustment/temperature sensitivity could be a cause.

632 Regal
03-26-2006, 01:42 AM
clean your AFM.

winfred
03-26-2006, 08:56 AM
you check it with a multimeter on ohms to check for contennuity, theres 3 pins the center being common, one outer pin is wide open throttle and the other is closed, you want it to click just as the throttle closes, if someone has been playing with the throttle you want to set throttle plate to be as closed as you can adjust it without it binding up as you open it, then set the tps so it clicks

nariusb
03-26-2006, 11:36 AM
Thanks Winfred, I'll follow your instructions on throttle tonight and look for a continuity at closed and open and it should click at closed. How does motronic behave if the throttle doesn't click/malfunction?

Thanks 632 Regal, you on the right path too, because I just did a 19lb injector replacement and installed m30 AFM on my m20 which gives me more air. So I do need to fine tune the ratio. Now I don't have LC1 or even simple f/a gauge so I tuned it by "feel/sound". Do you have any suggestions on how loose the spring has to be and what possition the screew has to be in, etc?

nariusb
03-26-2006, 12:06 PM
Ok, just tested my throtlle switch. I have voltage from ECM. There's no continuity at either idle or full open. When I move throttle the continuity flashes on DMM momentarily. This probably meens it's out of udjustment. I guess I have to take the throttle out to udjust it, right? Do I simply turn swith until I get continuity at idle?

SRR2
03-26-2006, 01:54 PM
It's more likely defective than out of adjustment -- the way they're mounted it's not likely that it would lose its original setting. They don't last forever, particularly on manual trans cars. Unfortunately, it's tricky to replace on the M20 living under the manifold as it does. If you have a manual and more than 100000 miles on it, just buy a new one.

And yes, a misadjusted AFM can do bad things to idle and throttle response.

nariusb
03-26-2006, 03:44 PM
Ok, readjusted the switch, I'm getting very very little resistance on idle and open and it clicks for close/idle.
Now this is important! My switch has rectangular not round connection. I read that automatic, like mine, should have a switch that's round.
Is there any difference/importance to one or the other for my automatic m20 525i?

winfred
03-27-2006, 08:20 AM
m20s had the 3 pin rectangular for ether tranny


Ok, readjusted the switch, I'm getting very very little resistance on idle and open and it clicks for close/idle.
Now this is important! My switch has rectangular not round connection. I read that automatic, like mine, should have a switch that's round.
Is there any difference/importance to one or the other for my automatic m20 525i?

nariusb
03-28-2006, 07:40 AM
m20s had the 3 pin rectangular for ether tranny
That's a relief, Thanks Winfred.
I forgot to mention, that I took the switch apart and it was full of oily liquid from cleaning my throttle body, I gave a good cleaning, readjusted and it's like new.