86 carrera vibration
#1
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Thread Starter
86 carrera vibration
My drivetrain goes through a resonance at ~2600-2900rpm. Happens in all gears, but the engine revs smoothly in neutral with or without the clutch engaged. Is this normal for these cars? My mechanic keeps telling me its running great but I'm not convinced!
Brian
Brian
#4
RL Technical Advisor
80% of the time, its caused by wheel and/or tire issues. Once in awhile, brakes.
Other, more obscure causes are engine related or clutch problems. Damaged pressure plates or clutch discs can create the vibration you feel, however I'd do a power balance check to confirm that ALL cylinders are doing the same amount of work.
Other, more obscure causes are engine related or clutch problems. Damaged pressure plates or clutch discs can create the vibration you feel, however I'd do a power balance check to confirm that ALL cylinders are doing the same amount of work.
#5
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If the vibration is more when you accelerate, not coasting, check driveshafts CV-joints. Quite normal problem with FW driven cars that have done some mileage.
The CV joint don’t center the shaft as there are play.
The CV joint don’t center the shaft as there are play.
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#8
My 1986 had this same resonance with the stock chip. It disappeared with an Autothority chip (back in the day...) and remains gone with the Steve Wong chip now. I am confident its the engine not the trans/wheels.
#9
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Thread Starter
Tires & clutch are new. In any case the vibration is related to engine speed, not vehicle speed, but is only apparent under load.
n8kruger: Thanks, that's very interesting. I think I'll call Steve about this.
Brian
n8kruger: Thanks, that's very interesting. I think I'll call Steve about this.
Brian