New and need help.

[Greenpea]

I have a 2002 Sierra with 5.3V8, have installed Comp Cam 212/218 522/529 114LSA. Also have Throttle body spacer and shorty headers with drop in K&N airfilter. At idle I have a very bad lope as it warms up, but changes to a mild lope after it warms up. Have toyed with some changes but only made things worse so I went back to original settings. It acts like it is too rich as it warms up, and when it loads up, sometimes it trips the SES light with a code P0300 misfire. If there is anyone near me that could give some pointers, or drop a message here, that would help. Would really like to get this thing ironed out. I live near Indy, thanks.

[jimmyblue]

Lose the vortex spacer and the K&N filter sez I, clean the
MAF of any K&N oil crust and check out this snappy bit of
narrative:




Spooky, huh?

[Greenpea]

Thanks Jimmyblue, after reading your thread, today I took off the TB spacer. The MAF sensor looked ok, but I gave it good cleaning just in case. Then using some of the things you changed in your thread, I made some changes using HP Tuners, and I must say I was impressed. Never in a million years would I have guess that the spacer was the root of my problem. The engine now idles with 17 inches of vacuum, and the lope is almost all gone. Lower end has alot more guts now too. Thanks for your help.

[jimmyblue]

I don't think the spacer is resposible for all that; it just
was driving me nuts with that dog-whistle noise and
I'm against them on principle (of spending mod money
on things that don't help).

But some things are worse (like a K&N that makes
your tune degrade over time for example).