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Discussion Starter · #1 ·
Driving to dinner tonight, I accelerated and as I got into 9-10lbs boost all of a sudden the car fell flat on its face and I got a pulsing sound and feel through the car. I let off and it went away. Tried to accelerate with boost again and it did the same thing. It quickly got progressively worse, to the point where I turned around to head home. It seemed to pulse/vibrate worst in the 1-2k range, smooth out from 2-3k and then get bad again around 4k revs. Didn't pu**** above 4k. Even at idle th whole car shakes. Exhaust sounds odd too. Sound and vibration seems to be coming from the transmission area. Revving the engine with the trans in neutral it still vibrates. Slight burning smell is noticeable as well, like burning cultch, but there is no disconnect between engine revs and speed, like with a slipping cultch. Can engage gears fine.

What on earth is this, and can I limp it to the mechanic on Monday or should I tow it?

Apologies, on my phone. Will try to post videos of the behavior if I can.
 

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At idle does it feel like it wants to stall? Possibly try disconnecting the battery or pulling a fuse to reset the car. Shouldn't hurt to try.
 

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Discussion Starter · #4 ·
How's your boost gauge behaving?
Boost was building fine till the fluttering started, then it would just stop and hold about 10lbs of boost. I can't even get it into boost anymore though. I push the gas and there's just no power, even before boost should kick in. It just starts vibrating, but revs normally.
 

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Discussion Starter · #5 ·
At idle does it feel like it wants to stall? Possibly try disconnecting the battery or pulling a fuse to reset the car. Shouldn't hurt to try.
No stalling, it runs fine, just like its out of balance. Something that's spinning with the engine is clearly out of balance.
 

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Boost was building fine till the fluttering started, then it would just stop and hold about 10lbs of boost. I can't even get it into boost anymore though. I push the gas and there's just no power, even before boost should kick in. It just starts vibrating, but revs normally.
Check for boost leaks?
 

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Discussion Starter · #7 ·
Check for boost leaks?
The whole car shakes just at idle, but I'll check tomorrow when it's light out. Don't think it's boost related, except for the fact that pushing power in boost caused it.
 

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Discussion Starter · #8 ·
Suspected are the DM flywheel and ignition system. No lights or warnings though.
 

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i had similar symptoms when i unplugged my MAF, try unplugging it and if it runs better it is the MAF and if it runs the same then you can rule it out? someone correct me if i'm wrong....
 

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Have the coils and plugs ever been changed? Could it be a misfire?
 

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Discussion Starter · #12 ·
It tries to build boost, but it's really vibrating too much to push it to build boost.thinking maybe a coil is bad.
 

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I had the same kinda symptoms when I had a bad coil but I got a CEL.
 

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Discussion Starter · #16 ·
I had the same kinda symptoms when I had a bad coil but I got a CEL.
Was the CEL immediate? Will try unplugging the MAF, but don't want to have that throw a code or CEL and then not see the CEL or lack of CEL from a coil.

A bad coil should throw a CEL right? I drove it for about 15-20 minutes like this, no CEL. Shut it down and restarted it, still no CEL.
 

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Was the CEL immediate? Will try unplugging the MAF, but don't want to have that throw a code or CEL and then not see the CEL or lack of CEL from a coil.

A bad coil should throw a CEL right? I drove it for about 15-20 minutes like this, no CEL. Shut it down and restarted it, still no CEL.
A bad coil will not throw a CEL light in most cases that I have seen. If your car has more than 50K miles, you might ad well replace the coils and plugs if you haven't already.
 

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Was the CEL immediate? Will try unplugging the MAF, but don't want to have that throw a code or CEL and then not see the CEL or lack of CEL from a coil.

A bad coil should throw a CEL right? I drove it for about 15-20 minutes like this, no CEL. Shut it down and restarted it, still no CEL.
Almost innediate. About 5mins after. Didn't have a code reader so I couldn't read the code myself but they replaced the bad coil and all was well.
 
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