Bellyman
Veteran Member
Hoping maybe you guys can give me a few clues on this one.
First off, my serpentine belt tensioner is bouncing like crazy when at idle. I'm assuming I need a new alternator pulley.
I get some vibration from it at idle, as expected.
But I seem to be getting a lot of vibration at higher speeds and I was trying to decide if it's related or a separate issue.
New cam went in about 700 miles ago. And it runs smoother than it did before, especially in the 1200 to 1500 rpm range.
The "sound" from the muffler at highway speeds seems to be a nice steady note, just like I would expect, not a "missing" kind of sound.
Acceleration seems to be very good, lots of "umph" when pressing on the go pedal.
Fuel economy seems to be doing about like always, 46 or 47 mpg, which is about what I normally get.
I'm in the middle of a trip and not close to any tools or anyone I know so much more than a cursury glance under the hood is about all that's likely to happen.
I seem to be getting a lot of vibration at engine speeds between about 2000 rpm and maybe 2500 rpm, which seems to work out to the area between 60 and 70 mph. Honestly, the last few hundred miles have felt like I've been riding in a giant orbital sander.
It definitely is tied to engine speed and not vehicle speed. The vibration doesn't go away when letting off the throttle completely but it is made more intense by heavy throttle.
I can understand how the bouncing serpentine belt tensioner can cause some vibration at idle. That's pretty obvious with that thing bouncing like it is. But would that translate to severe vibration at higher speeds?
It seems like if I were having an injector issue, I'd be going through extra fuel. I'm not. If it were a DMF issue, I read a lot about clanks and clunks and rattles, none of which are present. I can hear just a bit of valve noise in the 1500 rpm range but nothing abnormal. There are no warning lights lit on the dash.
I forgot to check backpressure with a hand over the tailpipe but even though it sounds a lot like an exhaust leak, it doesn't let up when letting up on the throttle and I can't recall an exhaust leak causing so much vibration.
Just thought maybe I'd run it past you guys and see if some of you may have already been down this road and found the "aha" moment.
Thanks for any thoughts.
Brian
P.S. It's an '04 TDI Jetta wagon, 5 speed manual, 110,000 miles.
First off, my serpentine belt tensioner is bouncing like crazy when at idle. I'm assuming I need a new alternator pulley.
I get some vibration from it at idle, as expected.
But I seem to be getting a lot of vibration at higher speeds and I was trying to decide if it's related or a separate issue.
New cam went in about 700 miles ago. And it runs smoother than it did before, especially in the 1200 to 1500 rpm range.
The "sound" from the muffler at highway speeds seems to be a nice steady note, just like I would expect, not a "missing" kind of sound.
Acceleration seems to be very good, lots of "umph" when pressing on the go pedal.
Fuel economy seems to be doing about like always, 46 or 47 mpg, which is about what I normally get.
I'm in the middle of a trip and not close to any tools or anyone I know so much more than a cursury glance under the hood is about all that's likely to happen.
I seem to be getting a lot of vibration at engine speeds between about 2000 rpm and maybe 2500 rpm, which seems to work out to the area between 60 and 70 mph. Honestly, the last few hundred miles have felt like I've been riding in a giant orbital sander.
It definitely is tied to engine speed and not vehicle speed. The vibration doesn't go away when letting off the throttle completely but it is made more intense by heavy throttle.
I can understand how the bouncing serpentine belt tensioner can cause some vibration at idle. That's pretty obvious with that thing bouncing like it is. But would that translate to severe vibration at higher speeds?
It seems like if I were having an injector issue, I'd be going through extra fuel. I'm not. If it were a DMF issue, I read a lot about clanks and clunks and rattles, none of which are present. I can hear just a bit of valve noise in the 1500 rpm range but nothing abnormal. There are no warning lights lit on the dash.
I forgot to check backpressure with a hand over the tailpipe but even though it sounds a lot like an exhaust leak, it doesn't let up when letting up on the throttle and I can't recall an exhaust leak causing so much vibration.
Just thought maybe I'd run it past you guys and see if some of you may have already been down this road and found the "aha" moment.
Thanks for any thoughts.
Brian
P.S. It's an '04 TDI Jetta wagon, 5 speed manual, 110,000 miles.