Bad Vibration Under Acceleration.

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Nax

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I have a 94 320i with just over 200,000 km's on it.

Reacently when I accerate hard from moving slow or standstill, I feel an awful vibration in my rear end, as soon as I back off a little the vibration stops.

I know the easy way to stop this is not to accelerate hard, but there is no fun in that and I am worried that it may get worse.

I have a feeling that it may be axle tramp.

Does anybody have any ideas what may be causing the problem?

Also, while I think about it, does anybody know of an aftermarket chip for an E36 320i?

Nax.
 
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Kirby

Kirby

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Nax said:
I have a 94 320i with just over 200,000 km's on it.

Reacently when I accerate hard from moving slow or standstill, I feel an awful vibration in my rear end, as soon as I back off a little the vibration stops.

I know the easy way to stop this is not to accelerate hard, but there is no fun in that and I am worried that it may get worse.

I have a feeling that it may be axle tramp.

Does anybody have any ideas what may be causing the problem?

Also, while I think about it, does anybody know of an aftermarket chip for an E36 320i?

Nax.
Click to expand...
Mmm, something lost in the translation? What's the "axle tramp"? Never heard that term before....
 
Chesty Bonds

Chesty Bonds

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Sounds like it could be a worn diff to me... Get the car checked out at your mechanic because you really don't want to do any uneccessary damage to your drivetrain. Sounds expensive...
 
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Nax

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The axle tramp I was refering to was a term from long ago when car had non independant rear ends and leaf springs. What happened, was when the car was under load, the axles, if slightly out of balance would casue the diff to shudder and bounce on the spring. I know it's unlikey to happen on an IRS rear end, but I was hoping that it might give people a better idea what I was talking about.

I will be going to my local dealer to see if he can shead some light onto my problem, I am really hoping it ain't the diff, cos it would probably be more economical to pass it off before it gets bad!

I did think that it may have been the flex coupling on the front of the diff, but alas, when I looked, I have a universal joint, so knocked that on the head. With any luck it will just need a new set of rubbers under the rear end, if they are still the stock ones from 200,000 k's ago, I am tipping they may be the cause of my problem.

Also chesty, since your also from Melbourne....do you know who sells after market chips for the E36 series? Seems finding them for a 320i is like looking for that missing sock!
 
Chesty Bonds

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Nax said:
Also chesty, since your also from Melbourne....do you know who sells after market chips for the E36 series? Seems finding them for a 320i is like looking for that missing sock!
Click to expand...
Hey i didnt even notice you were in Melbourne!! I'm not really in the tuning market but i can give you two places that i know will source performance chips for BMWs.

1) www.bmtech.com.au (just hit the 'performance' link)

2) www.autologic.com.au

Actually, Autologic have a very good reputation. They do projects, servicing, repairs, basically everything to do with BMWs so i'd definitely check them out. I think they're based in Brighton if that helps.

Let me know how you get on with the car mate.

Pete.
 
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Nax

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Well BMtech have a chip for the 320i, but damn, $880.00 AU is more than I am willing to pay for a $3 chip with a little fancy programing [B)]

I think I will do some hunting about and see what else I can find. Would love a Jim C chip, but alas, he skipped the 320i.

Maybe I should hunt down the software myself and program one [idea] I am sure with enough hunting, I would be able to find a spec sheet on the original chip and work out where I want the changes.
 
Chesty Bonds

Chesty Bonds

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Nax said:
Well BMtech have a chip for the 320i, but damn, $880.00 AU is more than I am willing to pay for a $3 chip with a little fancy programing [B)]
Click to expand...
Yeah isn't that just the biggest load of shit you've ever seen? That's why i reckon its really only justifiable on a car like an M3 or something...
 
N

Nax

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Heck, if I can get the software, I will start making them too, I guess if they sell em for $880, I can ask $400 each and not feel bad about it.
 
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epj3

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It takes them hundreds of hours and know-how to remap the engine software. Remember, it takes a smart guy to make the original engine software. It takes a SMARTER guy to reverse engineer it, and then make it AGAIN but even better.

For my car, its a 13hp gain and 15lb-ft torque gain. To me that is definitely worth it.
 
mjbst111

mjbst111

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vibration under acceleration.... things to check:

Flex disk
Center support bearing
Universal joints.

to check the universal joints you have to remove the axle.... check to see if they do not move freely.
Flex disc and center support can be diagnosed with the eye. torn up or play in them, etc.

Good luck
 
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