Hey guys, I going to try to discribe this so bear with me, first off I have an 01' L with most of the standard bolt on's, it's not a daily driver and has 20k on the clock, reciently I noticed that upon decelleration the truck seems to move down in RPM's in steps and almost stumbles, the truck run great, starts great but it has never done this before, it's not consistant either, I don't have a check engine light but I'd like to know what it is and don't know where to start? Thanks, Todd

 

S/C belt slip? If i recall you had an upper pulley on there. Maybe your are getting some belt slip and it's interupting the air flow pattern? Shot in the dark but good luck. Sucks whenever something doesn't seem right.

 

Mecca, The belt is about a year old, maybe 5k and still feels a little waxey. I'm still running the stock upper but your correct I did buy a 2lb upper but changed my mind. It's just a wierd problem of sorts and it's not constant which are both a bit frustrating. Thanks for the effort Mecca, Toddo

 

Mine tends to do the same thing. I think its the backpressure in the exhaust from the magnaflow. I can always get it to do it coming down one certain hill on the merrit pkwy. What you are experiencing could be totally different, also I don't know what exhaust you have. Is it after a WOT romp or just normal decelleration from a cruising speed?

 

it happens during both a wide open stomp and occationally from crusing speed, as for my exhaust kooks long tubes, high flow cats and a single muffler magnaflow cat back. I've had this exhaust set up for about a year and a half, it just seems more noticable, I was thinking the same thing maybe it's just exhaust back pressure. Thanks for the input, T

 

I've got the mid pipes w/ high flow cats, and cat back. (No long tubes though). Mine does the same thing on deceleration ever since I put in the mid pipes. You should see the a/f ratio jump all over the place while it does it! I would say it's just back pressure.