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Mathew
10-12-2002, 08:23 PM
I pulled up to a red traffic light and stopped for a few moments. I looked down at the gauges, and i noticed that the rpms were bouncing between approx 1,250 and 1,750. When i first saw it, i pressed down on the brake even harder to make sure i was still, and it kept on bouncing. I put it in park, and it went away, but it came back in drive.

Is this normal? Ive never noticed it on my 325Ci, or any other BMW :dunno:
rost12
10-12-2002, 09:30 PM
Our 745i got this too, this is what everybody calls "rough idle" at the roadfly.org.
There's no certain fix for it ( buying a MB might cure this, though :) ) as far as I know.

My dealer said none of the possible solutions (from my FAQ) work, and I'm not pissed of enough to go do something about it.
LowTech
10-13-2002, 09:33 AM
FYI - This does not happen at all to mine. Idles steady as a rock.

Hmmm... Rost, Our build dates are similar...
MMAfia
10-14-2002, 06:23 AM
hmmm... never seen this problem either...

MMAfia
rost12
10-14-2002, 07:10 AM
Originally posted by LowTech

Hmmm... Rost, Our build dates are similar...

Draw of luck? :)

On ours it happens all the time while it is in D and stoped. With AC off and on, when the car is cold or warmed up. Sometimes it's worse some times barely noticeable.

I don't care! I just sealed 'n' glazed 'n' waxed the black beast, it shines real purty :bigpimp:
in_d_haus
10-14-2002, 07:42 AM
According to the factory service rep this is "normal" due to the lean condition they have to run the car at for emissons.
Ack
10-14-2002, 07:50 AM
This happened to my car and I had to have the throttle control module replaced. I had to shut my car off and turn it back on to get it to stop. It was very random and quite annoying. You might want to get it checked if it happens regularly.

Then again, this was on my E46, so the new E65 might not even have this module.
MMAfia
10-14-2002, 08:06 AM
yo rost12... do u have any pix of yer black beaut? sapphire?

MMAfia
rost12
10-14-2002, 08:10 AM
MMafia - Yup, black sapphire. I've got some old pics in my faq, nothing new since I waxed it yet.

Pete - I also have had rough idle on my 3-er occasionaly, guess I'll have to go bug the dealer about throttle module now :)

In_d_haus - How do rpms that jump and down contribute to less emissions? :dunno:
Mathew
10-14-2002, 09:04 AM
I was wondering if it was the rough idle thing, or something with the throttle. Other than the weird obsevation, i dont really feel anything else thats wrong. the cars not jerky at near idle speeds, and it accelerates up smoothly like it should.

As long as it doesnt affect the driving, which it hasnt, im not worried about it.
Ack
10-14-2002, 10:07 AM
Originally posted by rost12
Pete - I also have had rough idle on my 3-er occasionaly, guess I'll have to go bug the dealer about throttle module now :)


It doesn't count when you're revving your engine to race someone . . .:p
rost12
10-14-2002, 10:14 AM
I never rev my engine! It doesn't sound menacing at all.
And I don't race :)

I just drive..um..quickly :eeps:
LowTech
10-14-2002, 11:12 AM
Wondering if it could be related to the fuel pump rotational speed recall? Don't think it would be the IVM or SIM modules.... Any shimmy from the motor associated with this?
rost12
10-14-2002, 01:22 PM
I didn't get any recall notices :dunno:
I'll drop by the dealer and ask.
LowTech
10-14-2002, 03:47 PM
Recall probably did not apply to yours, but sometime in mid-May(?) BMW started using the fixed part. It did not apply to mine, but have them run your VIN... I can live with the electronic growing pains and my quibbles with the software design, but basic mechanical operation (whether computer-controlled or not) is paramount for me...
ChrisTO
10-26-2002, 08:31 PM
seeing that these cars lack a throttle..i wonder if it has to do with that valvetronic device that is causing the rough idle problem? perhaps it's not regulating itself properly to keep the valves open sufficiently.
Originally posted by ///Mathew
I was wondering if it was the rough idle thing, or something with the throttle. Other than the weird obsevation, i dont really feel anything else thats wrong. the cars not jerky at near idle speeds, and it accelerates up smoothly like it should.

As long as it doesnt affect the driving, which it hasnt, im not worried about it.