VWDieselParts.com

Your place to buy VW Parts
It is currently Mon Jul 28, 2014 7:32 pm

All times are UTC - 5 hours




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: Excessive vibration in gear at idle, but not neutral. Why?
PostPosted: Tue Jun 26, 2012 3:15 pm 
Offline
Cetane Booster

Joined: Sat Oct 15, 2011 7:26 pm
Posts: 94
So, my 83 rabbit seems to idle fine. If I put it in gear, I get some vibration that seems a little excessive. If I turn the AC on, it sounds/vibrates like its a helicopter getting ready to take off. :/

If I put it in neutral with the AC on, its nice and smooth. I changed all the motormounts about a month ago, so I don't think that's it. I also turned up the idle a little. Driving its nice and smooth.

The other threads here on vibration didn't mention a difference between being in gear or not, so I thought I'd mention it and start a new thread.

Ideas?


Top
 Profile  
 
 Post subject: Re: Excessive vibration in gear at idle, but not neutral. Wh
PostPosted: Tue Jun 26, 2012 4:02 pm 
Offline
Turbo Charger

Joined: Tue Nov 08, 2011 12:04 am
Posts: 302
Location: Grants Pass, OR
I've got a little bit of this too, mine is no doubt because of the long belt stretched up to the alternator with the AC compressor removed. One example is when I first start up and the alternator hasn`t engaged yet, its smooth. Once the revs pass 950 rpm or so the alternator kicks on and the vibrations start. They really aren`t out of control but I think the issue is in the belts/accessories systems for you.

Did this start after all of the work you recently did to the accessories? Is it really in the engine compartment or just your dash vibrating like crazy? My dash vibrates a lot more with the knee pad out (while working on stuff), and with the passenger door open. These cars rely on the knee pad and the closed doors for a lot of the structural rigidity.

Someone else will probably come along with a lot better explanation and solution though.

_________________
Image
1979 Rabbit NA 1.6 250k
WANTED list


Top
 Profile  
 
 Post subject: Re: Excessive vibration in gear at idle, but not neutral. Wh
PostPosted: Wed Jun 27, 2012 8:57 am 
Offline
Turbo Charger

Joined: Wed Jun 20, 2007 1:44 pm
Posts: 4670
Location: Green Bay, WI
Is this an auto trans you're talking about, or manual trans? When you put it in gear, is your foot on the clutch pedal or is the vibration when you're letting the clutch out?

When you redo motor mounts, you will take a sloppy mount and tighten it up, so you can potentially take any vibrations that the sloppy mount let the engine flop around and as the engine is held more secure, the vibration will go into the chassis.

_________________
Everybody else lists their cars here - but not me.

I have too many to count


Top
 Profile  
 
 Post subject: Re: Excessive vibration in gear at idle, but not neutral. Wh
PostPosted: Wed Jun 27, 2012 12:54 pm 
Offline
Cetane Booster

Joined: Sat Oct 15, 2011 7:26 pm
Posts: 94
I have an automatic tranny.

Its just weird to me that putting it in gear and stopped it vibrates so much. The AC being engaged with the tranny in Neutral is nice and smooth.

I don't know what the vibe was like before the work I did, because it wasn't running prior to that. I could have waited on the motormounts and maybe that would have shed some light.


Top
 Profile  
 
 Post subject: Re: Excessive vibration in gear at idle, but not neutral. Wh
PostPosted: Wed Jun 27, 2012 1:31 pm 
Offline
Turbo Charger

Joined: Wed Jun 20, 2007 1:44 pm
Posts: 4670
Location: Green Bay, WI
Is there a solenoid anywhere or other provision that raises the idle RPM when the engine has the AC turned on? If it does, that's probably the reason why it idles smooth when the AC is on. Maybe you can hotwire that solenoid so that it's manually operated (along with auto operation with the AC) or that it's always on??

_________________
Everybody else lists their cars here - but not me.

I have too many to count


Top
 Profile  
 
 Post subject: Re: Excessive vibration in gear at idle, but not neutral. Wh
PostPosted: Tue Jul 03, 2012 9:38 pm 
Offline
Turbo Charger

Joined: Sun Nov 11, 2007 7:28 pm
Posts: 216
Location: Ottawa , Canada
just a suggestion:

try turning the idle DOWN .... as the rev's increase, the auto tranny engages the clutch packs ( starts to lock up ) and transmits the engine pulses to the drive train.

_________________
1992 Jetta (gasser to TD 1.6)
2000 TDI Jetta
1990 Jetta (Gasser RIP @ 875,000Km)
1976 Rabbit (RIP)
1972 Superbeetle (RIP)
1971 Fastback (type 3 RIP)

A pessimist is a well informed optimist


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 4 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group