Bad engine vibration
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Instructor
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Bad engine vibration
All of the sudden my 89 is vibrating like crazy. When the air is on its almost unbearable. It does it in any gear (including neutral. Zf6) from about 2400-3000 rpm and then tapers off. With the air off its much more faint but i can still feel it. Ive never done plugs, wires, cap, rotor, any of that tune up stuff since ive had it. Im hoping its just a misleading misfire. Pulleys seem okay. Belt and tensioner are fairly new. So is the smog pump delete pulley. Looking for insight since i really dont know where to turn.
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Thread Starter
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Team Owner
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Pull the serpentine belt and run the engine.
Take it for a drive. Not far, just enough to trouble shoot the vibe.
Remember the water pump is shaft driven by the opti not the belt.
Take it for a drive. Not far, just enough to trouble shoot the vibe.
Remember the water pump is shaft driven by the opti not the belt.
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Burning Brakes
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From: Auburn Michigan
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From: Phila., PA burbs
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Hmm i dont think so. Defintely more of a vibration not a knock. Its so consistent. I may do a tune up regardless and see what happens.
Thats the FIRST thing i would do!
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Changed plugs, cap, coil, rotor, wires, pcv valve. I think its actually running worse. And my vibration hasnt changed at all. Pretty dissappointing especially considering the horrible coniditon of the old parts. The wires were practically crumbling in my hands.
Melting Slicks
Joined: May 2014
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From: New Port Richey FL
you know folks I think we are missing a key fraise here he claims the vibration is with A/C on I agree with a few posts back release the drive belt to rule out things. but truly I think the A/C compressor has seen its last hot day, or some kind of over pressure.
Last edited by s carter; Aug 28, 2014 at 07:00 PM.
Burning Brakes
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From: Illinois/Wisconsin Line
Post a video with a clear glass of water half full on the dash and tell me have you pulled the belts and run it that way to see if it goes away or stays the same? That would help get to it