oh. never mind.

 

Did you see what the idle trims are yet?

 

If your throttle blade is completely shut, unplug your iac and get it to idle where it's supposed to, then plug your iac back in. Then adjust your RAF.

 

102 RT / PTM 102 cable here. No mods to intake or TB. Tuning characteristics are completely different from what I would consider the "norm," on this setup. Basic principles still apply. The major difference is how much by pass air you get from the 4" opening / throttle blade. Conventional cable driven TB tuning dictates that you shoot for 40-60 IAC counts when fully warmed up. 78-90ish mm TBs OK, 102 different animal.

The basic principal of getting the physical set screw and "position" of the IAC valve (your RAF in your tune) lined up where the valve can do it's job and provide needed additional bypass air is entirely dependent upon understanding that first and foremost the IAC valve only has so many "useable" counts and can only travel at one speed commanded by you via the pcm in your tune.

Any preliminary adjustments to the TB set screw should only be made when the motor is fully warmed up. That's where it's going to end up and live. Everything else is accomplished by the IAC via your software.

I have found with the 102/102 combo warmed up a reading of "0" IAC counts in park is not necessarily a bad thing. Drop it into gear and I get a reading of 60 counts.

What are your IAC counts at idle fully warmed up in Park? Gear?

 

I wish I knew the secret for how my LSXRT runs so well, I just left all the tuning to Patrick G and he got it dialed in.

My cam is a 115 LSA, and I'm running the 92mm TB. Don't know if either of those makes a difference. Maybe the porting makes a difference?

 

is this a cable run throttle body? if so i fought idle problems for YEARS until i modified the throttle body.

disconnect the IAC

log your truck (while turned off) and set the closed throttle position to between (.48-.53).

now check your WOT voltage (with truck off) make sure that WOT voltage doesnt go above 4.70 (otherwise it is likely to set a SES code)

to reset the IAC valve....unplug IAC valve. turn truck to "on" position for 5 seconds. turn to "off position". plug in IAC and start the truck.

let the truck come up to idle temp and check your idle IAC counts and get back with us. check with both in neutral and in gear sitting in place.

i had to drill my blade pretty damn large before my truck wanted to idle correctly. once i got the IAC counts in the 60-80 range at idle, the tune fell into place like butter. the 247/255 cam started cold, revved and came to a stop without a single hickup. I was pissed that i didnt drill my throttle body YEARS ago. if it is physically impossible for your motor to get the air that it NEEDS with the blade closed, it is impossible to tune out an issue.

 

The issue I have other than all the other crap I mentioned, is regardless of it having a messed up idle that will kill on u 40-50 times a day (no exaggeration), if I give it a little gas it goes a little lean. If I give it a lot of gas it goes very lean.

For example, I give approximately 50% tps it goes to 20-21:1 afr with the commanded eqr set to 1.10. And 1.00 eqr set to 14.43 as stoich. As it hits that lean it spits stumbles and then the injectors "catch up" and it goes rich as commanded, then I let off and it goes Super rich.

I believe that it is a vacuum leak because of a crap unit. If the above is not an indication of a vacuum leak let me know and help me out with how to fix it going so lean. Cant tune a vehicle that changes afr at the same given tps all over the place, ve tuning makes it more lean.

Im removing it tomorrow and putting on the stock intake. Luckily without spending more on fasts fuel rails it requires u to butcher ur oe fuel rail....so thats nice and will certainly be fun to attempt to continue to use on the original intake.

Ive wasted countless days on this crap that I could have been doing something else worthwhile on...so I love that too.

 

Don't give up

 

Definitely done with it.

Its removed now. Putting back stock intake.

Probably will go with a ported gen 4 intake later.

 

these lsxrt 102 intakes are known to be warped...known to leak...known to flex/inflate with vacuum/boost....and probably the only intake on the market I would never consider running.

FAST did a complete swing and miss with this intake. when it seals, it runs great at WOT. 99.999% of the time, our street trucks are not at WOT.