993 front to back movement when lifting off the loud pedal
Discussion
Hi all,
I've always had a slight problem getting a quick start from a standstill. Basically it’s difficult to get the clutch/accelerator movement smoothly enough to fire off the starting line. For example trying to get a clean getaway from traffic lights ...... I kinda have to slip the clutch more than needed to make a smooth takeoff. It can be embarrassing when the transit van next to you is pulling away quicker. After that pulling through the gears is fine, it's just 1st to 2nd.
Anyway, last year I replaced my original worn engine mounts for C4 ones (mine is a C2) and that helped alot with takeoff and gearchange, the sharpness at clutch takeup was much less and much better.
What I'm still suffering from is basically I'm accelerating in 2nd gear and if for some reason I liftoff the throttle, you can hear a 'bump' sound .... ie it feels like the transmission (or something) is moving back to front (or is that front to back), You can drive around it by being easier on how you drive the car. For anyone who has driven a LR defender, it feels like when the fourwheel drive and the props engage when accelerating...... unless in that circumstance your easy with the clutch takeup
Could this be caused by a worn mount on the transmission, and if so which one, or is there another engine mount forward of the engine that I've never heard of?
Hope you can help, and hopfully the above makes sense. Sorry for the waffle.
I've always had a slight problem getting a quick start from a standstill. Basically it’s difficult to get the clutch/accelerator movement smoothly enough to fire off the starting line. For example trying to get a clean getaway from traffic lights ...... I kinda have to slip the clutch more than needed to make a smooth takeoff. It can be embarrassing when the transit van next to you is pulling away quicker. After that pulling through the gears is fine, it's just 1st to 2nd.
Anyway, last year I replaced my original worn engine mounts for C4 ones (mine is a C2) and that helped alot with takeoff and gearchange, the sharpness at clutch takeup was much less and much better.
What I'm still suffering from is basically I'm accelerating in 2nd gear and if for some reason I liftoff the throttle, you can hear a 'bump' sound .... ie it feels like the transmission (or something) is moving back to front (or is that front to back), You can drive around it by being easier on how you drive the car. For anyone who has driven a LR defender, it feels like when the fourwheel drive and the props engage when accelerating...... unless in that circumstance your easy with the clutch takeup
Could this be caused by a worn mount on the transmission, and if so which one, or is there another engine mount forward of the engine that I've never heard of?
Hope you can help, and hopfully the above makes sense. Sorry for the waffle.
thegoose said:
It does sound like a gearbox mount, which is something I've had to replace on a 993 before.
Is it something you can replace without dropping the transmission ? Ie an easy fix?I thought itmight be this, but looking at the parts diagram, I was unsure if this was good only for side to side rather than front to back. (Part 23 in the parts manual comes to mind if memory serve)
A clunking DMF would have failed by now and would be making all sorts of orrible noises which you dont seem to be having.
Front mount on a 964/993 gearbox looks a bit like this:
So if its failed/failing you could imagine the gearbox would move around as you describe. There is a 2nd part to the front mount (can be seen towards the bottom of the pic) which could also fail or maybe missing - again would allow the movement you describe.
You need to get it checked out really as you dont know what the gearbox is resting on if the mount has failed.
Front mount on a 964/993 gearbox looks a bit like this:
So if its failed/failing you could imagine the gearbox would move around as you describe. There is a 2nd part to the front mount (can be seen towards the bottom of the pic) which could also fail or maybe missing - again would allow the movement you describe.
You need to get it checked out really as you dont know what the gearbox is resting on if the mount has failed.
Jevvy said:
A clunking DMF would have failed by now and would be making all sorts of orrible noises which you dont seem to be having.
Front mount on a 964/993 gearbox looks a bit like this:
So if its failed/failing you could imagine the gearbox would move around as you describe. There is a 2nd part to the front mount (can be seen towards the bottom of the pic) which could also fail or maybe missing - again would allow the movement you describe.
You need to get it checked out really as you dont know what the gearbox is resting on if the mount has failed.
Blimey, I'm guessing thats a gearbox out job then? I'm guessing a new clutch may well be fitted at the same time, or notFront mount on a 964/993 gearbox looks a bit like this:
So if its failed/failing you could imagine the gearbox would move around as you describe. There is a 2nd part to the front mount (can be seen towards the bottom of the pic) which could also fail or maybe missing - again would allow the movement you describe.
You need to get it checked out really as you dont know what the gearbox is resting on if the mount has failed.
Wozy68 said:
Do it myself do you think, I'm assuming you would have to support the transmission, all is better to leave to the pros?
Depends on your spanner skills really and yes you need to support the transmission while you remove the mount and bush.This looks like the bush you would need:
http://www.type911shop.co.uk/shop/article_6885/964...
And a few pics of the process:
http://forums.rennlist.com/rennforums/993-forum/66...
Might be worth having a good look with a torch first so you dont order parts you dont need.
Good luck dude
I had a failed DMF (about 5 degrees slack) and the only noise it made was a gentle thump when pulling away. Slowing down using the engine as a brake wound it up and pulling away exposed the slack.
Diagnosed within two days of purchase from well known but now rebranded OPC in the north-west. Not covered by Porsche warranty = no more business
Seemed fair to me!
Diagnosed within two days of purchase from well known but now rebranded OPC in the north-west. Not covered by Porsche warranty = no more business
Seemed fair to me!
Fastfred said:
I had a failed DMF (about 5 degrees slack) and the only noise it made was a gentle thump when pulling away. Slowing down using the engine as a brake wound it up and pulling away exposed the slack.
Diagnosed within two days of purchase from well known but now rebranded OPC in the north-west. Not covered by Porsche warranty = no more business
Seemed fair to me!
Mine the other way around, a thump when lifting off, pulling away is fine.Diagnosed within two days of purchase from well known but now rebranded OPC in the north-west. Not covered by Porsche warranty = no more business
Seemed fair to me!
Cheers Jevvy for your help. I think torch first and have a look. Then decide if its a specialist job....... Though I am tempted to have a go.
Edited by Wozy68 on Monday 25th February 21:49
Just to finish this off. If your 993 suffers from it, get over it.
Mine was in at the specialist and they have informed me that its old, your worrying to much and give it more welly when pulling off. They had a good look, took it for a good test drive and found nothing amiss
Well it seems I have been well and truly told, and since, for some bizarre reason the old girl seems pretty damn fine.
Mine was in at the specialist and they have informed me that its old, your worrying to much and give it more welly when pulling off. They had a good look, took it for a good test drive and found nothing amiss
Well it seems I have been well and truly told, and since, for some bizarre reason the old girl seems pretty damn fine.
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