General Miata Chat A place to talk about anything Miata

Severe Engine Vibration

Thread Tools
 
Search this Thread
 
Old 12-15-2014, 08:34 AM
  #21  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,499
Total Cats: 4,080
Default

Originally Posted by LTurner1
The vibration started waaaayy before the clutch change, I'd say a good 8/9 months probably. Whereas the clutch was only done a few weeks ago. That's why I don't think it's anything to do with that.
I was going to suggest the drive shaft was maybe not installed correctly somehow.

The damper on the diff could be bad.
Braineack is offline  
Old 12-16-2014, 03:25 PM
  #22  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default





As you can see, that's the coil pack end of the lead in question, and to compare to one of the normal ones. Do you think that would be enough to cause issues? Certainly doesn't seem right to me?

This is the coil pack itself...



Any way to clean inside there? or do I need to look at getting a replacement coil pack too?
LTurner1 is offline  
Old 12-16-2014, 05:10 PM
  #23  
Elite Member
iTrader: (4)
 
hornetball's Avatar
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,301
Total Cats: 696
Default

Originally Posted by LTurner1
Any way to clean inside there?
Originally Posted by hornetball
Make sure to clean the coil pack lead sockets with a metal bottle brush and use dielectric grease at both ends.
We were way ahead of you bud.

Breakdown/degradation of spark plug leads is a well-known maintenance item with these cars. That corroded end would have a lot of resistance and could be responsible for a high-RPM misfire.
hornetball is offline  
Old 12-16-2014, 05:14 PM
  #24  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

My bad for missing that comment.

Will need to source some of that dielectric grease, not sure where sells it in the UK without ordering online.

Will update with progress when done. Thanks guys.
LTurner1 is offline  
Old 12-16-2014, 05:19 PM
  #25  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,499
Total Cats: 4,080
Default

not having grease is not your issue.
Braineack is offline  
Old 12-16-2014, 05:28 PM
  #26  
Elite Member
iTrader: (4)
 
hornetball's Avatar
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,301
Total Cats: 696
Default

Originally Posted by Braineack
not having grease is not your issue.
The grease helps with assembly (helps you feel the "clicks") and keeps out water to prevent future corrosion. It does not enhance conductance.
hornetball is offline  
Old 12-19-2014, 05:57 AM
  #27  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

Ok, cleaned up the coil pack and fit the new leads along with the grease, car feels different, much smoother and appears to rev a lot better so I'm guessing that corrosion definitely caused these issues.

As for the vibration, still there!

However, spent some time poking around the back of the engine and noticed the bracket that holds one of the pipes/cables. Sits just above the slave cylinder, and is normally fastened to one of the looms with a cable tie but normally gets cut off when a clutch change is done. I think this might be the bloody cause after all this time, I poked it about as it's hard to get at and the vibration seemed different so I think I've ACTUALLY FOUND THE CAUSE!

Will update tomorrow as it was raining and very cold so I gave up!
LTurner1 is offline  
Old 12-23-2014, 06:41 AM
  #28  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

Ugh I give up.

Engine mounts seem ok, leads only seemed to make it run smoother rather than be a cause of vibration.

Wondering whether it is just the engine being broken, or breaking, in some way.
LTurner1 is offline  
Old 12-23-2014, 07:49 AM
  #29  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,499
Total Cats: 4,080
Default

is the damper still on your diff?
Braineack is offline  
Old 12-23-2014, 07:56 AM
  #30  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

Originally Posted by Braineack
is the damper still on your diff?
This happens when in neutral and revving. So it can't be gearbox, prop or diff related?
LTurner1 is offline  
Old 12-23-2014, 08:03 AM
  #31  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,499
Total Cats: 4,080
Default

did you post a video of this happening yet?
Braineack is offline  
Old 12-23-2014, 09:33 AM
  #32  
Junior Member
iTrader: (1)
 
BarbyCar's Avatar
 
Join Date: Apr 2007
Location: Toronto, Canada
Posts: 469
Total Cats: 25
Default

It is supercharged, check the mounting bolts for the bracket, check the bracket for cracks. I believe it also has an under brace, check that.

When you rev the engine, does the supercharger move relative to the engine? It should not.

Remove the belt and rev the engine through its range, does the vibration change?
BarbyCar is offline  
Old 12-23-2014, 10:04 AM
  #33  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

It's not really something I can video, and the car isn't supercharged, I think that the supercharger caused the vibration to start and it's maybe worse now 8 or so months on?
LTurner1 is offline  
Old 01-04-2015, 03:47 PM
  #34  
Junior Member
Thread Starter
 
LTurner1's Avatar
 
Join Date: Mar 2012
Location: Manchester, UK
Posts: 171
Total Cats: 30
Default

Well, the engine vibration just... disappeared?

I did a few jobs on the car, had to put the old downpipe back on (this was on before when it was vibrating), changed a damaged wing, changed the turbo inlet piping, fitted a boost solenoid, and some bits and bats.

I can only assume that I dislodged something when I was changing the downpipe.

I'm so happy, turned the boost up and been enjoying the car since
LTurner1 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 04:21 PM
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM
nbdooey
Miata parts for sale/trade
9
08-30-2017 09:50 PM
90 Turbo
MEGAsquirt
19
10-19-2015 03:23 PM
tazswing
Race Prep
20
10-03-2015 11:04 AM



Quick Reply: Severe Engine Vibration



All times are GMT -4. The time now is 05:33 PM.