Posted: May 22 2008 at 11:21am | IP Logged

So I installed a Gibson cat back exhaust and K&N cold air intake on my 2000 Desert Runner and so far I'm not real impressed.  My mileage is exactly the same as before, I noticed a definite drop in low end power after the exhaust but before the K&N, and now with the CAI it seems to be back to stock.  I've felt a small improvement in my 60-80mph acceleration but that's about it.  Granted, I might be enjoying the new exhaust sound a little too much and that might be why my mileage is still the same.  Also, the idle seems to be a little high.  There doesn't appear to be an official idle speed printed on the sticker under the hood- is there no adjustment on these trucks?  Anyone know what the idle speed is supposed to be?

All in all, I will say everything went on really smoothly.  The instructions for the K&N were some of the best I've encountered and everything fit perfectly. 

Posted: Jun 04 2008 at 6:07pm | IP Logged

Well here's another update if anyone cares.  The K&N tech said my high idle was probably due to a vacuum leak.  I checked in there but couldn't find anything (there's no check engine light) so I turned the idle adjustment screw in(?) 2 turns and got the fully warm idle back to normal.  When it's cold it still idles too high.  My mileage today is at 19.1, before it was usually around 18.5.  Although, last week I made a real effort to drive much slower than normal so the increase could be from that.  So far, not much improvement.

Posted: Jun 05 2008 at 9:24am | IP Logged

That's great.  Thanks Frontierguy.  I'll adjust my idle the right way this weekend.  I hope you like to post to forums- 25+ years, that's priceless.  The Gibson does not include a Y-pipe, it attaches to the flange just rearward of the Y.