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Do the interns get Glocks
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Discussion Starter · #1 ·
I need some assistance diagnosing a problem that started two weeks ago.

It started as a small vibration when I would accelerate from a standing start after the car was warm. It was just a little shudder that made me think transmission or guibo disk.

The problem has slightly grown worse until today when it got very bad. It ran fine for about 30 minutes and then at a stop light it started vibrating very dramatically.

From that point on it settled down but the shudder under acceleration was much more pronounced.

There has been a rather loud ticking noise coming from the front of the engine which I attributed to the legendary Vanos knock. But now it seems to be a bit louder than it has been in the past.



The Particulars:
96,000 miles
Auto trans
Conforti chip installed at 60,000 miles w/o problem and have run 93 octane since.
Oil changed regularly - last change was less than 1,000 miles ago.

Exhaust seems solid with no obvious problems from looking at it.
Plugs were changed with the last service - used oem spec Bosch.
Leaking valve cover gasket has also been replaced and hasn't leaked since.
Two hoses from the PCV valve were also replaced as they had split open due to age.

Whats going on????:dunno:
 

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BMWCCA 149159
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2,876 Posts
Vibration

You need to jack the car up and look at the guibo and see if it is shredding or what is going on. If you can jack the rear up and put it in neutral you can rotate the drive shaft and see if the guibo is starting to head south. Because it seems to come and go that is a good sign that it is driveline related. The driveshaft is weighted for balance too and an out of balance shaft that has lost a weight might do that too................
 

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Do the interns get Glocks
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9,324 Posts
Discussion Starter · #3 ·
fun2drive said:
You need to jack the car up and look at the guibo and see if it is shredding or what is going on. If you can jack the rear up and put it in neutral you can rotate the drive shaft and see if the guibo is starting to head south. Because it seems to come and go that is a good sign that it is driveline related. The driveshaft is weighted for balance too and an out of balance shaft that has lost a weight might do that too................
How long do guibos last. It was replaced shortly before I bought the car with 44K miles.

Based on descriptions of what a guibo sounds like going bad I sort of discounted it.
Also, even in neutral and when at a stop the engine is still sputtering.

I think it may be vacuum hose related as it is somewhat affected when I step on or let off the brakes. I looked at all the hoses I could see under the hood and didnt see anything obvious.
 

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Do the interns get Glocks
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9,324 Posts
Discussion Starter · #4 ·
How do I test for a bad coil pack?

I think the problem is related to the spark...either a plug, coil pack or the ECU.

The car is only running on five cylinders.
 

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Guibo???

Sorry, this won't help you at all, but what's a guibo? I've been around cars for many years and never heard of it.
 

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it does sound like you might be running short a cylinder, recently I had the same probelm in one of my other cars, not a BMW, and I didnt understand why but I guess over time they just wear down but in this particular case it was rather odvious since it had cracked the housing for it. But anyway the vibration can be caused by a sprk plug that wont fire cus obviously when you aint running on all cylinders you will have a shake while accelerating and even in idle sumtimes.
 

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Do the interns get Glocks
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9,324 Posts
Discussion Starter · #7 ·
diablo2668 said:
it does sound like you might be running short a cylinder, recently I had the same probelm in one of my other cars, not a BMW, and I didnt understand why but I guess over time they just wear down but in this particular case it was rather odvious since it had cracked the housing for it. But anyway the vibration can be caused by a sprk plug that wont fire cus obviously when you aint running on all cylinders you will have a shake while accelerating and even in idle sumtimes.
Ill ahve to check the plugs but assuming the plugs are OK how do you diagnose a bad coil pack?
 

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Do the interns get Glocks
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9,324 Posts
Discussion Starter · #8 ·
Anyone, Anyone....Bueller...Bueller
 

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Do the interns get Glocks
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9,324 Posts
Discussion Starter · #9 ·
Well it was indeed a coil pack. Thanks for all your help...:rolleyes: :p

Now, for what I could have fixed myself I am going to have to pay about $150 in labor.

Anyone figure out how to diagnose a bad coil pack?
 
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