Crack this nut. The return of evil vibration!
03-28-10, 01:42 AM
#26
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Just something I thought of. I do not have ACV (blocked off), since I'm running RB exhaust, and I have also unhooked and removed the switching and relief solenoid valves (on the firewall) and capped the two vac nips on the LIM. So I just have a direct line going from LIM to the vacuum switch by the washer fluid.
Could that affect anything at all? Make the engine run rough of misfire?
Obviously I still have the 5th and 6th port actuators still hooked up to the exhaust tube going into the presilencer.
Could that affect anything at all? Make the engine run rough of misfire?
Obviously I still have the 5th and 6th port actuators still hooked up to the exhaust tube going into the presilencer.
03-30-10, 05:49 PM
#27
I highly doubt that a vacuum leak or electrical system problem or exhaust clog will be the issue to your vibrations as it has already been mentioned. It must be something in the rotational assembly.
You haven't ruled out everything that's been already suggested have you?
You've checked the transmission and engine mounts already I presume.
Someone mentioned to check the pulleys. Disconnect all the belts and see if your vibrations go away or remain or perhaps slightly get less.
Then check out your flywheel. If you remove the starter, you can visually inspect some of it. Check for any mismatched bolts attaching the clutch assembly to the flywheel (one bolt caused vibrations for my 7 and after replacing the flywheel since a the thread was stripped 99% of the vibrations went away).
Also I would do a compression check with a tester to check the compression at each face.
Good luck with troubleshooting your vibration issues. Hope you can enjoy the smooth rotary power soon!
You haven't ruled out everything that's been already suggested have you?
You've checked the transmission and engine mounts already I presume.
Someone mentioned to check the pulleys. Disconnect all the belts and see if your vibrations go away or remain or perhaps slightly get less.
Then check out your flywheel. If you remove the starter, you can visually inspect some of it. Check for any mismatched bolts attaching the clutch assembly to the flywheel (one bolt caused vibrations for my 7 and after replacing the flywheel since a the thread was stripped 99% of the vibrations went away).
Also I would do a compression check with a tester to check the compression at each face.
Good luck with troubleshooting your vibration issues. Hope you can enjoy the smooth rotary power soon!
03-30-10, 09:44 PM
#28
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If you had an out-of-balance rotating assembly, maybe you can describe it for me:
1) Did it vibrate the same under load, WOT, half throttle, off throttle, and when revving in neutral? I imagine it would, if it's unbalanced.
2) What RPM range was the vibration most severe? Did it smooth out past a certain RPM in any gear? Did it shake more or did it shake less at idle?
3) Was there any weird noise? Or did it sound just like a normal engine?
Any info you can remember would be awesome. Thanks.
1) Did it vibrate the same under load, WOT, half throttle, off throttle, and when revving in neutral? I imagine it would, if it's unbalanced.
2) What RPM range was the vibration most severe? Did it smooth out past a certain RPM in any gear? Did it shake more or did it shake less at idle?
3) Was there any weird noise? Or did it sound just like a normal engine?
Any info you can remember would be awesome. Thanks.
03-31-10, 01:01 AM
#29
If you had an out-of-balance rotating assembly, maybe you can describe it for me:
1) Did it vibrate the same under load, WOT, half throttle, off throttle, and when revving in neutral? I imagine it would, if it's unbalanced.
Yes it would vibrate under load or without the car moving even with the clutch pedal pressed down.
2) What RPM range was the vibration most severe? Did it smooth out past a certain RPM in any gear? Did it shake more or did it shake less at idle?
The RPM range where the vibrations were most severe was around 3000 and then came back around 6000 rpms so it was vibrating more pronounced in periods or cycles. Really though your engine is always experiencing the vibrations throughout all rpms. It did not really shake too much at idle.
3) Was there any weird noise? Or did it sound just like a normal engine?
When the vibrations were not so pronounced, somewhat. When they hit the range where it was most pronounced it didn't sound right.
Any info you can remember would be awesome. Thanks.
1) Did it vibrate the same under load, WOT, half throttle, off throttle, and when revving in neutral? I imagine it would, if it's unbalanced.
Yes it would vibrate under load or without the car moving even with the clutch pedal pressed down.
2) What RPM range was the vibration most severe? Did it smooth out past a certain RPM in any gear? Did it shake more or did it shake less at idle?
The RPM range where the vibrations were most severe was around 3000 and then came back around 6000 rpms so it was vibrating more pronounced in periods or cycles. Really though your engine is always experiencing the vibrations throughout all rpms. It did not really shake too much at idle.
3) Was there any weird noise? Or did it sound just like a normal engine?
When the vibrations were not so pronounced, somewhat. When they hit the range where it was most pronounced it didn't sound right.
Any info you can remember would be awesome. Thanks.
03-31-10, 05:47 PM
#31
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if you still have the fan mounted on the front of the engine, believe it or not, that damn thing likes to be put on in a particular orientation. So, if you've got the fan on the front, unbolt it, turn the base 90 degrees, bolt it back on, start and rev engine, rinse and repeat.
I had a real nasty vibration when I went to add a belt that the PO didn't put on after... anyways.. check that front fan if you still have it.
I had a real nasty vibration when I went to add a belt that the PO didn't put on after... anyways.. check that front fan if you still have it.
05-03-10, 03:47 PM
#33
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So I drove it a bit today and there was no vibration. It was in fact quite smooth at first. It did get a bit more vibratey after driving it for a bit and getting it warmed up, but still nowhere near the harsh vibrations I had the other time.
Pretty odd, considering I haven't changed anything. Still same rotating assembly, still same tranny, same clutch, same flywheel. If it were any of those, it would vibrate any time I drive, and regardless of whether the car is hot or cold. I did get an S5 pulley, but I doubt it had any effect. I had the same situation with the old pulley, where it sometimes would vibrate and sometimes it wouldn't.
Thus I think it's a vibration caused by an uneven ignition/combustion, that gets worse as the engine warms up. I have been working on that, and still am. Once I sort it, we'll have to see if vibration goes away. I've never heard of anything like that causing a vibration... but who knows.
Pretty odd, considering I haven't changed anything. Still same rotating assembly, still same tranny, same clutch, same flywheel. If it were any of those, it would vibrate any time I drive, and regardless of whether the car is hot or cold. I did get an S5 pulley, but I doubt it had any effect. I had the same situation with the old pulley, where it sometimes would vibrate and sometimes it wouldn't.
Thus I think it's a vibration caused by an uneven ignition/combustion, that gets worse as the engine warms up. I have been working on that, and still am. Once I sort it, we'll have to see if vibration goes away. I've never heard of anything like that causing a vibration... but who knows.
05-03-10, 06:04 PM
#34
84SE-EGI helpy-helperton
"Running on one rotor"??? Search here and read my experience.
The vibration you describe could be mistaken for that scenario.
(Cliff's notes version: check your fuel injector plus at the front harness)
The vibration you describe could be mistaken for that scenario.
(Cliff's notes version: check your fuel injector plus at the front harness)
05-03-10, 07:18 PM
#35
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Ok, found the thread. The thing that throws me off is that I'm not really experiencing noticeable lack of power when it vibrates. I have new injector connectors, and I've tried wiggling the harness with no effect. Also, checking at ECU, both injector wires have 12V.
Is this something I could test by simply pulling leading wires from one rotor at a time and seeing if that makes any difference at all?
I am dealing with lack of idling...as can be seen in the other thread. Might be related. Although it won't idle even when the car runs smooth.
Is this something I could test by simply pulling leading wires from one rotor at a time and seeing if that makes any difference at all?
I am dealing with lack of idling...as can be seen in the other thread. Might be related. Although it won't idle even when the car runs smooth.
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