PDA

View Full Version : Vibration at Idle in 1990 535i Auto and Other Issues; Please Help



an535i
10-31-2004, 11:22 AM
Been noticing a vibration through the entire car when idling parked in any selected gear (auto).. And when the A/C is on its worse! I can feel the inner parts of my ears pulsating from the vibrations...

Its worse in the mornings when the idle isnt as smooth ( time for the rest of the tune up)

What should i be looking at regarding this?? Transmission Mounts (both???) Or is there a specific trans mount on these 535i's that need to be replaced around 150k ?? Even though the motor doesnt seem to mvoe around much should i think about replacing the motor mouns as welll???


Also, I have noticed a dramatic increase in tramlining in the last 5k miles.. seems to be worse on the wet roads, car wants to stear itself... I sold my lifted up truck with 35" tires to get away from the tramlining feeling..
Before we get into a discussion over tires: The car tramlines with stock wheels and new tires, and with +2 size wheels and new tires...



Here's a list of mods and recent fixes ive done:


1 New Tie Rod end 15k miles ago
2 Lemforder Thrust Arms w/ 750i Bushings 15k miles ago
4 Wheel Alignment / Balanced wheels 10k miles ago
2 Lemforder Sway Bar Links 10k miles ago

18" Hamann wheels, E.A.T Chip, Otherwise stock suspension with 155k miles on the car..

Any help is greatly appreciated to get me going down the straight and narrow again!!

Thanks in advance,
Deke

http://copper.takiweb.com/~sage/P1010183.JPG

Jeff N.
10-31-2004, 12:35 PM
Some questions:

At idle, does your idle stay stable at about 7 or 800 RPM or does it drop when you put it in gear and add accessories?

How smooth is the idle in neutral with no accessories?

Have you checked the throttle position sensor to make sure it's triggering "idle" when the car is at idle? (see bentleys)

Classic idle roughness is typically due to a vacuum leak somewhere in the system. Even a very small one. Have you really carefully checked:

- ICV lines and clamps
- 3 mm vac lines from manifold to FPR and valve cover vent
- AFM to throttle body hose and clamps
- valve cover vent line and clamps
- charcoal cannister vent line under manifold
- brake booster lines, check valve (cracks) and clamps

Did I say "careful"? Yes - I believe I did. Get anal as all heck and be sure to look *really carefully* and replace anything suspect. Be sure to dig around and really check the connections to the manifold. Yes, the ones that are hard to see and a pain-in-the-ass to check.

If that all looks good then try:

- spraying out the ICV with sensor safe carb cleaner
- new plugs, cap rotor
- adjust valves to about .012 or .013 cold
- check engine temp sensor to ensure it works to spec (bentleys will advise)
- carefully inspect plug wires and replace if old

Tramlining...sounds like you've done most of the typical suspension work. Could be your rim tire setup. My setup with 16"'s tramlined like heck with worn Yoko AVS db tires. Completely stopped with new Bridgestones. Any way you might try another rim tire setup to find out if it's the car or the tires?

Hope this helps,

Jeff

an535i
10-31-2004, 04:28 PM
First off let me say Thank you Jeff N. for the response! Very much appreciated and will followup on how the idle turns out..


Secondly lemme answer some questions that I can :
Idle speed is right around 700-800 ; fairly smooth idle not too much "hunting"

Idle is the same with all accessories Off as it is with them on -
(Air Cond. , CD Changer, 600W AMP)


"Have you checked the throttle position sensor to make sure it's triggering "idle" when the car is at idle? (see bentleys) "

Great suggestion! Thank you I will look this up in Bentleys Man tomorrow and check. Seems to idle around 700-800 in cold mornings as well ..

ok so im so that gives me some things to check there...
but

Thirdly Tramlining.........


what an absolute nightmare... I've got 2 sets of fairly new tires (less than 12k): one set Sumitomo HTR-ZII's 18" and another set Kumho 712's 15" .. and they both tramline.. (although i will admit the 18" wheels are worse)

The car is hardly even driveable every little variation in height (either side to side or forward to back) in the road sends my car a new direction.. It doesnt move the steering wheel as much as the car just seems to shift around and i have to adjust it constantly unless its a glass smooth road then everythings is copasetic.

is there any possible way the tramlining could be caused by either Struts, Shocks, Springs, Lower Control Arms, Wheel Bearings, or is it just a looney driver?

Thanks again for your guys help, this board is awesome!
Deke

Jeff N.
10-31-2004, 09:01 PM
Glad to lend a hand Deke. Just returning favors that others have shared with me.

I suspect it could be anything you mentioned contributing to the tramlining. The bigger the rubber, the more I suspect it's likely to occur. Maybe you might try taking the car to a good chasis and alignment shop for an evaluation. You might also have them check the rear subframe bushings too. I know how annoying this can be! Good luck!

Jeff

an535i
11-01-2004, 09:39 PM
Tested Throttle Postion Sensor ... Good,
Tested the ICV Resistance to Bentley, Good ..
Tested Engine Temp. Sensor was good as well ..

and relpaced a distributor cap and ignition rotor with O.E. parts :)
Man that cap is heavyy duty!

Idle has improved quite a bit and Im happy with it for now..

http://www.racingking.net/performance/Images/TransMounts.jpg

I guess regarding the vibration and noise I will maybe check this mount..
has anybody replaced one of those?

Trans Mount (http://www.racingking.net/Parts/PartDetails.asp?ProductID=62)

AllanS
11-02-2004, 09:16 AM
Mine tramlined a LOT when I overtightened the steering box via the allen bolt on the box itself. It felt fine, and very tight at low speeds, under 40mph, but when I got above that it went all to hell. It would require a swift movement of the wheel to correct. After playing with it, I got it "just right", and that was that.

It's very easy to adjust the steering box, you just need a 17mm box wrench and (I think 6mm?) allen key. It's also very easy to go to far with adjustments, so make a mark for reference.

Robin-535im
11-02-2004, 12:18 PM
Deke,

It may be a bushing in the rear that makes the car feel like it's wandering. When the rear has a broken bushing or some out-of-spec suspension part, it can make the car "float" side to side, and you'll feel it through your seat.

At 150k, you could have one of the rear bushings going out: Subframe, pitman arm, trailing arm, diff carrier mounts, diff mount. If I were to choose the most likely, and I'm not an expert here, I'd suggest you inspect the subframe bushings and the trailing arm bushings. I don't think the others would contribute to rear end wander.

HTH

Robin

Robin-535im
11-02-2004, 03:18 PM
nt

an535i
11-02-2004, 08:22 PM
Mine tramlined a LOT when I overtightened the steering box via the allen bolt on the box itself. It felt fine, and very tight at low speeds, under 40mph, but when I got above that it went all to hell. It would require a swift movement of the wheel to correct. After playing with it, I got it "just right", and that was that.

Ya I had adjusted the box a few times in the past, I think I had gone too far as you mentioned.. Well pulled the car on a rack and loosesened the 17mm nut; held the adjuster in place and turned the steering wheel from lock to lock untill finally. I was able to back it off about 1/4 turn ( ya i know i went way to far) and now it feels much better. Wanders alot less wow
Thanks Allan!

Also noticed my dogbones are shot, both collapsed and the dust shields blown out.. Does anybody have an E.T.K can look this part up for me??
Need BMW's part numbers if possible for the rear dogbones..
thanks in advance.

I will probably tackle that rear subframe bushing when I get some lowering springs and struts / shocks to replace my worn out suspension..
Which is the trailing arm bushing? i wasnt able to find that???

Thanks for all the help

AllanS
11-02-2004, 10:59 PM
I also noticed a drop in wandering when I went to slightly smaller wheels, 17x8.5/9.5 to 17x8 all around. New tires also did it a little, and it went away after a couple hundred miles.

I think the pitman arms are 33 32 1 126 476, and there's some other stuff related to that at Bruno's site http://www.bmwe34.net/e34main/maintenance/suspension/subframebushing.htm

If you call BMA and ask for Yves ot Patrick, they'll most likely be able to order the right part for you based on your description. With the pitman arms, for instance, there's a lot of small hardware in conjunction to it, and they'd be able to pull it up and get it all in one shot.

an535i
11-03-2004, 08:15 PM
Installed new pitman arm "connecting links" today, Meyle of coarse. Biggest improvement so far; that was definately a big part of the problem rear is much more balanced now and car gos through turns with less correcting ..
My question is: Do i need to do a 4 wheel alignment NOW because of removing those links and putting new ones in?
Or

Can I wait and put some new springs, and new struts / shocks and then do a 4 wheel alignment??


Thanks for the assistance ;
ps:
I sent my rotors out to get turned at a local parts store.. long story short : they began to cut one of the rotors and made it ALOT worse by doing so, now I have to get new ones.. I'm looking at 50$ a piece my supplier (O.E.M. Parts at a discount) vs. 30$ a piece at RacingKing.net .. Why are these so much cheaper and can anybody attest to their quality?
pss:
Do i have to put new pads on when i put new rotors on? Apparently the pads i have on there are harder than granite and after 20K miles still look the same hahah

AllanS
11-03-2004, 11:12 PM
I don't think an alignment shop would do much, if anything, with the rear. There's not really anything to adjust, afaik. When I replaced my springs/struts/thrust arms, the alignment shop didn't even touch the rear, and didn't do much with the front either. I drove around for a couple days before the alignment (took a week to get an appointment!) and afterwards there wasn't a difference. A year earlier I took it to a different shop, which specifically does alignments, and they said the same thing, there's nothing to adjust in the rear.

I wouldn't get rotors turned btw- it's a waste. You can read some stuff about it here:

http://www.garageboy.com/bmw/brakefaq.html

Buy new pads too, just to make sure they get to know the rotors properly the first time :)