I've posted about this before, and, since the search engine is temporarily off line, I thought I'd bring it up again.

My car: 98 GXE Auto, 102k miles.
Idle: 600 RPM
Mods: Frankencar, Budget Y

The super-rough idle started a couple months after the Y-pipe install. It has never stalled or even appeared to stall. No one can tell me what is wrong. My mileage is good. I drive it hard in the city, but on the highway I get as much as 33 mpg.

Does God just hate me?

When I stick the sucker in Neutral or Park, the vibrations disappear. It still isn't as butter-smooth as a new VQ30DE, but it's as close as 102k would get. Anyone have any thoughts? The idel is really rough, like a vibrating massage chair (I heard someone describe it like that once).

 

im not sure either.. but you may want to clean your throttle body, check plugs, and check coil packs

 

Have you changed the spark plugs? if not change the spark plugs..... and do a fuel injection cleaning.....
Recommend this product to everyone i know. check it out buy it its only 2.99...

http://store.yahoo.com/rodi/luc10020.html

 

have the same issue here; - the flex section on budget is much shorter than OEM y-pipe thus more vibration , also clean your TB and look for any torn engine mounts - stickin some rubber erasers there might help a bit.

other than that engine with over 100k will never run like swiss watch or new VQ

Nick.

 

What concerns me is that there are other VQs with more mileage that are still very smooth. My car went from smooth to almost rocky in two months and no exceptional mileage.

Damned down search feature.

 

my 99 max se does it to and i dont know why, i thought it was the tranny but who knows. i have 147,584 miles on mine