oscillating RPM

[Alpinweiße30]

I have recently replace the timing belt and water pump, did a valve adjustment and new spark plugs. Took the car out for a few test drives and notice a slight loss of power but it was...on then off, and so slight it was hard to notice. Today I was doing a little work on the cooling system and I was trying to warm the engine up while sitting in neutral revving the engine and notices this.

Sorry the video is sideways I didn't realize the phone wanted to be on its side for video.



http://www.youtube.com/watch?v=YsyWCuM6NX0

[SoopaGhetto]

...thats what my car is doing...:(

do you have starting issues? do you feel that pulsing when wot accelerating or during partial throttle accelerating/cruising?

[Alpinweiße30]

I do not have starting issues. I have only noticed this during partial throttle because I have not made it to wot yet. These are the suggestions I have gotten on my local board.

vacuum leak / idle control valve

If it isn't a vacuum leak or the ICV it could be a number of things but most likely air isn't registered somewhere...

Make sure the correct plug is on the afm and the throttle position sensor (they're the same plug...) and maybe adjust TPS.

...check the TPS or AFM you can unplug one of both and the car should default to an ECU default setting. If it goes away you may have found your problem. If not, try something else.

vac leak icv needing a cleaning

[Farbin Kaiber]

Did you reinstall the IAC backwards?

[Alpinweiße30]

Did you reinstall the IAC backwards?

never took it off

[SoopaGhetto]

Did you reinstall the IAC backwards?

not being an ass, but is that even possible with a two pin connector? i thought it doesnt matter since there is no distinct polarity going either pins of the icv?

[Farbin Kaiber]

Yes, I don't mean the f-'in plug, I mean the hoses. I had one that was backwards via the PO, I spent lots of money replacing working parts trying to fix a cyclic idle.

[Alpinweiße30]

Yes, I don't mean the f-'in plug, I mean the hoses. I had one that was backwards via the PO, I spent lots of money replacing working parts trying to fix a cyclic idle.

Thanks for the suggestion but I did not remove the hoses to the ICV

[Farbin Kaiber]

Awesome. Did you remove the coolant temp sender?

[SoopaGhetto]

Yes, I don't mean the f-'in plug, I mean the hoses. I had one that was backwards via the PO, I spent lots of money replacing working parts trying to fix a cyclic idle.

oh :mrgreen::mrgreen::mrgreen:

[Alpinweiße30]

Awesome. Did you remove the coolant temp sender?

um i don't believe so. where is is located?

[Alpinweiße30]

oh :mrgreen::mrgreen::mrgreen:

hahah

[Alpinweiße30]

Well I think I fixed it. Went out there yesterday and realized I had left the key in the ignition turned over to acc. The batt died. So tonight I went out there jumped it and let it run for a little. Tried the same thing with the throttle and no fluctuation in RPM. May this be a function of something that was disconnected when doing the timing belt/water pump, valve adjustment, or plugs? Just something that was reset because of the batt going dead?

Also now that the batt was dead the radio needs a code, is there a general one or am I F'ed because I did not get one with the car?

[SoopaGhetto]

is there a bmw dealer around you? they could get you the code if you have the head unit serial number or vin or something to that extent. they did it for free for me but some places may charge, so ive been told...

or you can find a program online somewhere. other than that...your f'd

you could guess the combination?

[gone002]

check your exhuast mainifold . mine did the same thing . it had a big ass crack