Lots of vibration in pedals and cabin - Please guess and suggest.
11-03-2017, 03:45 PM
#31
Rennlist Member
Thread Starter
3x more work? Eh, I don't know... I did my suspension (struts, springs, sways and drop links, and front wheel bearings) - it wasn't much less than dropping the engine/tranny. Granted I've got a C4 which is a little more involved due to the front axles. Dropping the engine/tranny is not difficult, but there are a whole bunch of ancillary things that need to be removed (under-body trays, axles, clutch slave cylinder line, transmission cables, suspension braces [cross brace and angle braces], rear sway bar, headers, mufflers/cats, rear bumper cover and other bumper parts, rear wheel liners [not totally necessary but it makes access and visuals much easier] all chassis to engine wiring connections, chassis to engine fuel line, coolant lines, power steering lines etc...- once again, not difficult but pretty involved - make sure you've got plenty of tape/labels and zip-lock bags/containers for nuts/bolts, connectors etc. The main thing I would recommend is that you get the car up much higher than it is in the photo. For me, the magic number was 25.5" and I was just able to roll the engine/tranny out from under the car. By doing my own work I saved about $5k - The way I like to look at it is that I payed myself $5k - perspective is everything!!! 
I will let my wife be the deciding factor if I do it or not when I show her the shop quote if it comes down to it. I could buy a small lift with the savings
11-03-2017, 04:34 PM
#32
Rennlist Member
Have you checked your CATS? I've never had one go bad but maybe someone with first hand experience could chime in.
11-03-2017, 05:00 PM
#33
Rennlist Member
Thread Starter
Haven't checked them. Was actually just reading something about that earlier. Someone said to test it just hit it a bit with a rubber mallet while the car is off to see if you can hear something moving in it.
11-03-2017, 05:52 PM
#34
Race Director
A chunking catalytic converter can add significantly to the noise, but the in-cabin NVH OP complains of sounds much more drastic than what I can attribute to a failing converter.
A bad cat is a "wow, that's annoying; even more with the window down" kind of sound, not a "lots of vibration in pedals and cabin" kind of sound.
I'm inclined to think that tenderizing several hundred pounds of wildlife with a single thump is profoundly involved with OP's issues, but I'm a sucker for the classics.
A bad cat is a "wow, that's annoying; even more with the window down" kind of sound, not a "lots of vibration in pedals and cabin" kind of sound.
I'm inclined to think that tenderizing several hundred pounds of wildlife with a single thump is profoundly involved with OP's issues, but I'm a sucker for the classics.
11-03-2017, 07:12 PM
#36
Pro
I’m with everyone on pulling the belly pans to inspect. That’s cheap. Inspecting the transmission mount is cheap. Just a couple of bolts while supporting the transmission.
That said, I will guess flywheel too. If it failed and is stuck weirdly it would cause vibration. Not crazy hard to replace but costs about $700. Plus it’s the kind of job that will have you spending on the clutch, RMS and IMS (unless you are sure when/how it was last done.)
I am doing a job like this now so a little too familiar with it right now.
Good luck.
That said, I will guess flywheel too. If it failed and is stuck weirdly it would cause vibration. Not crazy hard to replace but costs about $700. Plus it’s the kind of job that will have you spending on the clutch, RMS and IMS (unless you are sure when/how it was last done.)
I am doing a job like this now so a little too familiar with it right now.
Good luck.
https://www.partsgeek.com/catalog/20.../flywheel.html
Cheapest I could find (unfortunately do not ship to Canada).
And Ahsai did point me in this direction.
Last edited by Montychristo128; 11-04-2017 at 01:58 PM.
11-06-2017, 06:27 PM
#38
Rennlist Member
Thread Starter
Myself and 2 other mechanics looked over the bottom of the car thoroughly on Saturday and found nothing that could be the cause of the vibration. Also no animal remains on the bottom of the car. They actually brought up too that my exhaust sounded louder/different with more low end than last time I was there. It seems both unlikely the flywheel or the new motor mounts would alter the exhaust sound at all. I'm taking her in to a Porsche Indy on Wednesday morning for them to check out. Fingers crossed they figure it out at a reasonable cost.
11-17-2017, 12:51 PM
#39
Rennlist Member
Thread Starter
Took it to the pro's. They said out of balance flywheel and worn clutch. What a bummer. They also said my clutch pedal was about an inch higher than it should be which I found odd. Anyways looks like it's time to spend some money.
11-17-2017, 02:15 PM
#43
Rennlist Member
11-18-2017, 07:19 AM
#44
Drifting
How dies a flywheel get “out of balance”? Is that shop speak for a failed dual mass flywheel?