1991 S4 vibration at 3000 rpm w/cracked flex plate
#46
Nordschleife Master
Just noting that the pan is most likely not sitting on the crossmember. My mounts were squashed really bad (as bad as any I've seen pics of on here) and I still wasn't sitting on the crossmember.
#47
I've only had a few that the engine was actually touching the cross member and that vibrations is damn bad. One shop in OKC went so far to say that the issue was the LH brain and accused me of trying to steal business from him. After the LH was sent to me and it checked out good, the owner trucked it down to me. Funny, I didn't give a **** if I worked on the car or not. Car got here, I spent 20 minutes and fixed a $15.00 vac leak at the 4 way and called him. Put a rubber mat under the cross member and told him his vibration was gone. He asked what he owed me and I said $30.00. He laughed and had me do the timing belt, water pump and motor mounts.
Why did I share this? Just cause I wanted to, lifting the motor mounts just a 1/4 inch will tell you how bad other vibrations are.
#48
Nordschleife Master
I usually tell the customer that if the vibration and the oil drips are something that they can deal with, then it's just a "cosmetic" issue and can be dealt with last.
I've only had a few that the engine was actually touching the cross member and that vibrations is damn bad.
<snip>
Put a rubber mat under the cross member and told him his vibration was gone. He asked what he owed me and I said $30.00. He laughed and had me do the timing belt, water pump and motor mounts.
Why did I share this? Just cause I wanted to, lifting the motor mounts just a 1/4 inch will tell you how bad other vibrations are.
I've only had a few that the engine was actually touching the cross member and that vibrations is damn bad.
<snip>
Put a rubber mat under the cross member and told him his vibration was gone. He asked what he owed me and I said $30.00. He laughed and had me do the timing belt, water pump and motor mounts.
Why did I share this? Just cause I wanted to, lifting the motor mounts just a 1/4 inch will tell you how bad other vibrations are.
Didn't Jager sell something called a speed mat (speed mount?)? IIRC, it was a rubber mat to fit between the engine and member - jack up engine, fit ribber mat in the gap, and plonk the engine back on the rubber mat? ("plonk" = something done by a plonker ).
I'm guessing thats roughly what you did?
#50
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Thanks for all the posts per the motor mounts/cross-member information. My goals for this week are the following (in priority):
- Order the Jay Kempf tool (or something anyone can recommend) to check the TB tension - does anyone have one for sale?
- Create a parts list for all the TB replacement parts I'm going to need and get it on order. Thinking about Ed's water pump here (Gaurdian?).
- Motor mounts & cross member clearance : get some photos and measurements of the areas in question and report back.
Also, I have a mightyvac on the way and will be starting some basic vacuum diagnosis after I study the vacuum systems a bit.
Thanks All,
Mike
P.S. What is it with the polecat and gomjfb comments? Are these robot responses?
- Order the Jay Kempf tool (or something anyone can recommend) to check the TB tension - does anyone have one for sale?
- Create a parts list for all the TB replacement parts I'm going to need and get it on order. Thinking about Ed's water pump here (Gaurdian?).
- Motor mounts & cross member clearance : get some photos and measurements of the areas in question and report back.
Also, I have a mightyvac on the way and will be starting some basic vacuum diagnosis after I study the vacuum systems a bit.
Thanks All,
Mike
P.S. What is it with the polecat and gomjfb comments? Are these robot responses?
#51
Thanks for all the posts per the motor mounts/cross-member information. My goals for this week are the following (in priority):
- Order the Jay Kempf tool (or something anyone can recommend) to check the TB tension - does anyone have one for sale?
- Create a parts list for all the TB replacement parts I'm going to need and get it on order. Thinking about Ed's water pump here (Gaurdian?).
- Motor mounts & cross member clearance : get some photos and measurements of the areas in question and report back.
Also, I have a mightyvac on the way and will be starting some basic vacuum diagnosis after I study the vacuum systems a bit.
Thanks All,
Mike
P.S. What is it with the polecat and gomjfb comments? Are these robot responses?
- Order the Jay Kempf tool (or something anyone can recommend) to check the TB tension - does anyone have one for sale?
- Create a parts list for all the TB replacement parts I'm going to need and get it on order. Thinking about Ed's water pump here (Gaurdian?).
- Motor mounts & cross member clearance : get some photos and measurements of the areas in question and report back.
Also, I have a mightyvac on the way and will be starting some basic vacuum diagnosis after I study the vacuum systems a bit.
Thanks All,
Mike
P.S. What is it with the polecat and gomjfb comments? Are these robot responses?
#52
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Hi Everyone,
After a week of family time, I had very little time to invest into this project, but, I did manage to do something LOL.
I have the timing belt job parts list ready to order, but, I'll need to wait a couple weeks for my budget to get there. The car is going to be on ramps until that time so I'll be inspecting everything else I can. Per the budget, I'm trying not to spend too much per month (space out the big spending a bit) as I already spent quite a bit in April - neat tools and other misc. items add up
My mightyvac arrived last Friday and what a cool device! Very neat and easy to use. So I'm starting to do some vacuum checks:
-The first item I checked was the flappy valve operation per Dwayne's intake refresh write up. I used a permanent marker to mark the location and got really nice smooth movement with low vacuum. Vacuum held for > 10 mins too. Happy flappy!
- Next, I started assembly of the gauge/device Dwayne uses to attach to the top of the MAF. After some thorough sifting of the plumbing bins in my local hardware store, I have the device all built up. Going to give that a go this week as time allows and report back.
- The car has an inconsistent idle and based on my research thus far, I decided to attempt to test hoses, elbows, anything I could easily get to. I removed the elbow from the fuel vent diaphram and pulled very lightly on the thin plastic tube to see if it was attached to anything. There was resistance so I’m assuming it is attached to something. I then tried to pressurize it and I heard a strong hiss under the intake. Can someone confirm this line should hold pressure/vacuum?
- Is there a procedure listed anywhere that outlines testing the ISV in situ (if that's even possible)?
Thanks,
Mike
P.S. Sorry for the edits guys - my post is still in progress as I'm trying to figure this out, please bear with me.
After a week of family time, I had very little time to invest into this project, but, I did manage to do something LOL.
I have the timing belt job parts list ready to order, but, I'll need to wait a couple weeks for my budget to get there. The car is going to be on ramps until that time so I'll be inspecting everything else I can. Per the budget, I'm trying not to spend too much per month (space out the big spending a bit) as I already spent quite a bit in April - neat tools and other misc. items add up
My mightyvac arrived last Friday and what a cool device! Very neat and easy to use. So I'm starting to do some vacuum checks:
-The first item I checked was the flappy valve operation per Dwayne's intake refresh write up. I used a permanent marker to mark the location and got really nice smooth movement with low vacuum. Vacuum held for > 10 mins too. Happy flappy!
- Next, I started assembly of the gauge/device Dwayne uses to attach to the top of the MAF. After some thorough sifting of the plumbing bins in my local hardware store, I have the device all built up. Going to give that a go this week as time allows and report back.
- The car has an inconsistent idle and based on my research thus far, I decided to attempt to test hoses, elbows, anything I could easily get to. I removed the elbow from the fuel vent diaphram and pulled very lightly on the thin plastic tube to see if it was attached to anything. There was resistance so I’m assuming it is attached to something. I then tried to pressurize it and I heard a strong hiss under the intake. Can someone confirm this line should hold pressure/vacuum?
- Is there a procedure listed anywhere that outlines testing the ISV in situ (if that's even possible)?
Thanks,
Mike
P.S. Sorry for the edits guys - my post is still in progress as I'm trying to figure this out, please bear with me.
Last edited by msteiner805; 05-11-2015 at 02:15 PM.
#54
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Well, after some head scratching and research, I think I'm starting to understand the vacuum system a bit better.
Thanks to John Pirtle for this fantastic link, specifically the Intake manifold diagram
from the Workshop Manual, page 24-216:
http://members.rennlist.com/pirtle/svc_intake.html
This clears up the confusion I had earlier.
Per Dave's comments earlier regarding the 7 way vacuum testing - I now have a good mental picture of what to do.
Mike
Thanks to John Pirtle for this fantastic link, specifically the Intake manifold diagram
from the Workshop Manual, page 24-216:
http://members.rennlist.com/pirtle/svc_intake.html
This clears up the confusion I had earlier.
Per Dave's comments earlier regarding the 7 way vacuum testing - I now have a good mental picture of what to do.
Mike
#57
Rennlist Member
Jump post cover! Nice looking car, where are you located in CA?
#59
Nice color. From your pics it doesn't look like your MMs are collapsed. I'd expect to see the motor to be riding below transverse bar.
I think you want to check your vacuum lines that meet at the 5 way connector near brake master cylinder.
Good luck, lots to learn and check.
I think you want to check your vacuum lines that meet at the 5 way connector near brake master cylinder.
Good luck, lots to learn and check.
#60
Nordschleife Master
If you rest a straight edge on top of one of the intake manifold plenums, it should be resting flat on the intake and just touching the top of the strut brace.
One of those nice aesthetic details that the Porsche engine-bay designers came up with - it all lines up.