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mediashock
05-08-2010, 01:06 PM
i am getting a rough idle.. but no codes, fuel is 91 octane, i tried using seafoam in the fuel.. nothing.. as soon as i give some gas .. shaking stops

mediashock
05-08-2010, 02:10 PM
hmm so i found this... could be it.. anyone know which is the lower bracker for the exhaust system?

"Service Bulletin 18 02 08

Customer may complain of a slight vibration and/or droning noise when the vehicle is idling in park, neutral, drive and reverse when engine is at operating temperature.


CAUSE
Insufficient vibration dampening of the exhaust system.


PROCEDURE
1.Verify the complaint. Vibration/droning is most prevalent when engine is at operating temperature.

2.Remove the lower bracket for the exhaust system. If droning/vibration is gone, proceed to step three. If vibration/droning still exists with the lower bracket removed; continue troubleshooting exhaust/driveline for other causes or conditions

3.Remove complete bracket assembly and replace it with the bracket (1) PN 18 20 7 521 346 using two new ASA bolts (PN 07 12 9 905 417. Tighten to 21Nm.
Install front pipe bracket (1) PN 18 20 7 521 347 with four rubber bushings (2) (PN 18 20 7 546 579) to the new 346 bracket with two ASA bolts (PN 07 12 9 904 559) and two nuts (PN 07 12 9 904 580). Tighten down to 21Nm

After performing this procedure the vehicle will exhibit the same amount of normal driveline vibration as a comparably equipped E60 with a M54 or N52 engine."

Nube1kenobi
05-08-2010, 02:16 PM
Here's the picture you need... however I doubt that is your idling problem.

http://www.bmwtis.com/tsb/bulletins/bulletin_graphic_temp/B180208g.htm

skylolow
05-09-2010, 04:13 AM
I think there was a SIB about vanos timing when idling that causes an unsmooth idle.

Basically my understanding is the vanos on some cars have a hard time settling to a smooth idle at the factory set idle RPM. The dealership can adjust your idle up to 150RPM from the factory spec.. So they can play around with it and find a happy idle RPM for your car which smooths out your idle.

That is where I'd start unless there is more to your story.


P.S.: This is more common in six cylinders.

mediashock
05-09-2010, 06:41 AM
i am making an appointment this week to have them check it out..and i plan on mentioning these thigns. cause i have a feeling if i just tell them i have rough idling they will tell me everything is fine.

-Howitzer-
05-09-2010, 07:14 AM
i am getting a rough idle.. but no codes, fuel is 91 octane, i tried using seafoam in the fuel.. nothing.. as soon as i give some gas .. shaking stops

Couple of things you can do yourself before giving $$$$$ to the stealership:

This depends on the mileage of your car but what I'd do is:

1) Go to Autozone, buy CRC MAF Sensor cleaner. Its in a spray can and costs $6.

2) Open your hood, look at your air box.
3) Look at the tube that leads from the airbox to the engine. Notice in between that there is an electronic sensor mounted to the top of that tube. This is your Mass Air Flow Sensor or "MAF".
4) Get a T20 Torx screw and remove the 2 screws supporting the MAF.
5) Pull the MAF out gently
6) Spray the MAF in and out about 15 sprays and let it dry. (its 99% alcohol base and dries in seconds).
7) Put the MAF back in and start the car.

Your rough idle might very well be gone completely.


Option 2: Replace your spark plugs especially if you've gone past 50,000 miles. Then your rough idle will be gone with that and cleaning the MAF I'm almost 100% sure.

hantour
05-10-2010, 10:47 AM
Ask for a software upgrade. I had the same issue a few months back. The SA had me try a few tanks of chevron with tekron (said it was recommended by bmw). That didn't do anything, the software upgrade made a world of difference. Then they had me believe that the idle fluctuation was within tolerance, that's a bunch of bull. They won't offer it unless you request it most of the time.

mleerob
05-10-2010, 10:53 AM
i am getting a rough idle.. but no codes, fuel is 91 octane, i tried using seafoam in the fuel.. nothing.. as soon as i give some gas .. shaking stops

I had thei condition once.
Rough idle when the car was hot,and the idle slow.
I thought the engine was going to stall, unless I gave the throttle a push.

Ran that tank down further,and filled up with Shell 93, and it went away.
Have never had this problem since.

silverbimmer3
05-31-2010, 11:35 AM
Hi there... how did your visit to the dealership turn out?

Did you get a check engine soon warning light with the rough idle?

Thank you.

i am making an appointment this week to have them check it out..and i plan on mentioning these thigns. cause i have a feeling if i just tell them i have rough idling they will tell me everything is fine.

sjcloutier
11-15-2010, 12:02 PM
I took my 07 530 to the dealership for this issue as well an tick coming from the engine. My SA called and said the fixed the tick in the engine. I don't remember what they said was wrong but they recommended an injector cleaning to fix the idle issue. I immediately said no, since this didn't make since to me as the car has 40K on it and has only run 93 octane. That may have been an incorrect assumption but reading the attached service bulletin confirmed that I was right. It describes exactly what I am experiencing. I called my SA to talk about and he gave me attitude, saying there's no service light. I had to email the freaking bulletin to him because he couldn't find it. Just got a call from the SA saying the techs can't find the vibration, are you freakin kidding me. Now I have to go down there to replicate the problem for them, this is ridiculous. So I'll go there let the car get warmed up then, then let it idle in gear with that annoying sound so they can say "that's normal". I'm gonna be pissed if those words come out of their mouths. When I'm done with this service, I'm gonna request to be assigned to a different SA. My current SA told me it would be three hours labor to add the Sirius unit to my car, when I have an SB stating it's one hour. I feel like I'm dealing with a Ford or Chevy dealer doing the upsell. GRRRR!!!!

designwithenerg
08-17-2015, 03:51 PM
Hi, been searching around for an answer to this issue:

1. Rough idle, almost would not run - 1st time set codes (misfire on 3, 5) and found Vanos 3 hole spring plate clamp (outer 4mm ring) was loose... (must have tightened it against the shoulder, not fully seated... vibration broke loose-- immediately stopped and disassembled lids, and re-tightened, now staying tight.

(next day)

2. Subsequent drive today... ROUGH Idle! (check engine light, but NO CODES this time)
took apart again... Vanos fine, tight no issues.

3. Note: Given good throttle - will spin smoothly.

4. IMPORTANT: Car was sitting in garage for about 8 months... with 3/4 tank of gas - before testing above... filled up with premium. Still could be bad gas I guess.

Question: If Vanos unit looks normal, timing assuredly correct, cams line up and look healthy, etc, etc. ... Can this issue simply be bad gas in the tank? Can I drive it clean or recommend purge, and refill?

I can siphon it out and use for gas mower or something.

designwithenerg
08-17-2015, 04:04 PM
To be clear... I followed the procedure carefully for the vanos timing. I believe it is correct, or it would not run nice at all...even part of the time.

BUT... I don't think the vanos side (I have a single vanos M52 motor) slides super easy. It's tight because the spring plate applies good pressure.

Is that ok? or should it shift (rotate easy?)

This is the part of the vanos setup that has given me the most grief. I am not sure how even brand new parts in this case would make it less tight? (the rotation seems controlled by the spring plate which is pretty hefty and strong - when clamped down.

Any help or tips are welcome!

charly1
08-18-2015, 09:03 AM
Might be DISA valves... http://www.z4-forum.com/forum/viewtopic.php?f=34&t=36349

There are two DISA valves attached to intake manifold. the above is for the easy outside one. See if you can take out (30 mins) and look for the broken part...

designwithenerg
08-18-2015, 10:16 AM
I posted this to the wrong area... and since have done some work on sprucing up the fuel, which had been sitting idle in a garage (in the tank) for eight months, so I think the motor (e39 - 528i -- M52 ) is just being a bit snotty about the crappy gas.

I seem to be able now to drive it in hot weather after replacing the head gasket (and having the head crack fixed and referbished completely) and re-assmembling everything - with no hot running issues. It stays on normal heat solidly now.

It does occationally stumble here and there at low idle but I attribute that to the stagnate gas, and It'll most likely clear up fine after a tank or two.

I put some octane booster and lucas injector and upper lube in it... should drive itself clean now.

It spins up smoothly and runs very nice when given some good throttle, so I was just a bit spooked by the fact that I have never pulled this engine apart or put it back together before. I have built a 74 911 and that motor from the ground up... so I knew I could probably do it.

Sure enough it's going to work fine.

Now for that pesky A/C - it is not working at all. (106 deg in Sacramento) not comfortable at all to drive. NO SIR!

charly1
08-18-2015, 11:14 AM
Actually the same thing happened when my wife "accidently" put a lower grade gas...:mad:

designwithenerg
08-24-2015, 02:11 PM
Hi guys,

Completed an oil change, checked levels on coolant, tuned up gas with octane booster, etc...

now no issues. I just completed the smog... passed no problem... it's getting 20.6 MPG city /26+ Highway...

Temp gauge after head refresh - stays at normal (straight pegged at midpoint) and never moves or even a hint of moving no matter what even in HOT, HOT Sacramento CA afternoons. (95 - 106 deg F)

plus...

Best it has driven in years.

So I'd say this was a huge success, unexpected victory!!!!!!

Now to fix the sunroof, left window regulators (both) etc etc. It's a work in progress!

JohnnyTurbo
08-24-2015, 06:43 PM
Hi guys,

Completed an oil change, checked levels on coolant, tuned up gas with octane booster, etc...

now no issues. I just completed the smog... passed no problem... it's getting 20.6 MPG city /26+ Highway...

Temp gauge after head refresh - stays at normal (straight pegged at midpoint) and never moves or even a hint of moving no matter what even in HOT, HOT Sacramento CA afternoons. (95 - 106 deg F)

plus...

Best it has driven in years.

So I'd say this was a huge success, unexpected victory!!!!!!

Now to fix the sunroof, left window regulators (both) etc etc. It's a work in progress!

I get 21.5 mpg city so give it a few more days and it should improve a little more. ;)

designwithenerg
08-24-2015, 07:32 PM
This is how the car looked not long ago...

http://carphotos.cardomain.com/ride_images/3/2918/3141/32294070006_large.jpg<br>
http://carphotos.cardomain.com/ride_images/3/2918/3141/32294070001_large.jpg<br>
http://carphotos.cardomain.com/ride_images/3/2918/3141/32294070019_original.jpg