Radix idle issue update
 

I made reference in a couple of threads about my idle being erratic since I installed the Radix. It had been fine for the last year and never has died on me. Well since I installed the Radix, its had a hard time idleing properly. It often seems like its gasping for air and idle falls very low and its dies several times. This is usually when in gear coming to a stop or doing a slow take off. I turned up the rpms and some of the idle airflow values in LS1 Edit, which seems to have helped a little. I need to work with it more though.

Blownchevy said I should look at my fuel pressure regulator because it wasn't keeping fuel pressure built up for very long after shutting down. I bought my kit used and it already had a regulator installed when I got it. Here is what I found:

New O-ring on left, pinched O-ring on right
(sliver of rubber was sitting at the bottom inside the fuel regulator housing)
http://z71.net/oring.jpg

I installed a completely new regulator with super lubed up O-rings. Fuel pressure issue is gone, but idle issue is still there. Its not an high idle problem like an intake leak, its more like not enough air is getting past for a good idle.

Sounds like one problem is fixed and another showed its ugly head. I would look at idle tuning.....did you check the TB gasket?

It was a new gasket. I havne't pulled it off yet, but thats next.

K....if you need a new one I have the part number, or I can send ya one ;)

I do a lot of tuning and have installed a few mods since the radix. My truck idles low, searches for idle very regularly after the changes. Has always disappeared after a little driving. Have you allowed time for the pcm to "learn" to idle again?

Its typically gotten a little worse after learning. I put 100 miles on the last tune and it was OK. Next morning, it stalled twice in the grocery store parking lot.

The thing I find funny is that the tune had not changed and the idle was fine for over a year. What would give it this stalling problem? Is it a lack quick of air flow through the radix compared to having the TB mounted directly on the intake?

Anyone have a base superchips LS1 Edit read for an 03 truck?

Check the routing of your vaccuum hoses,it sounds like you crank case vaccuum hose is plugged.

You havent serviced and over oiled the K@N filter Have You? , if the oil creeps up the air tube into the MAF all kinds of weird stuff will happen, Just use contact cleaner or Brake clean and spay off the electronics and that will fix that problem, If that is what happening.

Have you rechecked the wire connections where you had to extend the wires for the electrical connectors on the throttle body? I didn't crimp one of mine enough on my 01 to the idle air controller and it had idling problems.

Sounds like a vacuum issue to me. Since you bought the kit used, the intake could've been warped during removal, not allowing it to seal properly. Checking all your fasteners, clamps and hosed is a good idea, and it couldn't hurt either.

Do you have a vac/boost gauge? If so, what is it doing while the truck idles bad and stalls? That will tell you a lot about vacuum leaks and such.