EA82 Engine Vibration

[peterf]

My 92 Loyale (recently purchased) has a very distinctive engine vibration starting at about 65 mph/ (guessing 3500 rpm). I can best describe it as a consistent cycle (frequency) of about 1.5 seconds and decreasing in frequency proportional to an increase in rpm. This probably make very little so let me just say that it feels exactly like a bad harmonic balancer. It's definitely a harmonic vibration beginning at the speed I mentioned. Do Subaru's have vibration dampener problems? Is this a good diagnosis on my part? TIA

peter

 

[johninKY]

The answer to your question I believe is no. Check the bolt that retains the balancer for tightness. Possibility the timing belts were recently changed and the bolt wasn't properly torqued. Is the vibration present if you just rev the engine out of gear? A broken engine mount could be the problem. Another is a tire with a broken belt.

 

[peterf]

Thank you that's a good point. I will check the torque. I'll need to check the no-load condition and see if it present. I'll post the results.

peter

 

[peterf]

Well it most definitely is engine rpm related. I haven't checked the torque yet but will soon. Any other thoughts on this?

 

[johninKY]

Flexplate may be cracked if an automatic.

 

[peterf]

Thanks, yes it is an automatic. Can you tell what the flexplate does and where it's located?

 

[johninKY]

Engines with a manual transmission have a flywheel. And engines equipped with an automatic will have a flexplate. It's that thing the torque convertor bolts to. Normally this part never fails but will fail sometimes after the engine and transmission has been separated because the bolts holding it to the crankshaft where not torqued enough.