I recently installed a complete TBSS Intake, 90 MM TB, and TBSS Injectors on my 2004 Silverado. I had Wheatley update the tune for the above. I originally had an issue with the PCV system which I think I have corrected but ever since the install I have had (2) codes: P0171 & P0174 (lean, both banks). From what I have read these (2) codes together tpyically are a result of vacuum leak after the MAF. I took the intake off and all looked well so I put it back on. No change. I need help. I am looking for suggestions on what to look for. The truck seems to run well, has good power. It will at time take a bit to get to an idle during driving but other than that it is fine. Any suggestions would be appreciated!

 

Check all connections to the manifold for a vacuum leak, manifold gaskets, injector/rail o-rings, and if you can't find an issue there....

Next take a look at the inlet of the fuel rail to see if there is an obstruction in either rail, or the entrance from the fuel line on the drivers side rail.

 

Have you noticed any increase with the tbss intake... I'm gunna put one on mine here soon and was just wondering I haven't talked to anyone that has one on a 5.3


If you wanna check for a vacumm leak around the intake take some starting fluid and spray around where the intake mounts to the heads and if it revs up you need some new intake gaskets...

 

I've checked all those things with both brake clean and propane with still no luck. The truck does not act like it has a vacuum leak. It is idling exactly like it was before the swap just with a check engine light. If I had a scan tool I could really see what is going on. I may have to try and access one to solve this problem.

As far as performance, I can honestly say that I feel a pretty good gain everywhere in the RPM range. I have not really got on it much because of the above issues but I feel it was a worthwhile swap.

 

It might be that the TBSS intake is flowing much more than the MAF is calibrated for causing the lean codes....the tuning may need to be tweaked a little.

 

I am stumped. I have no clue what it could be. I have experienced an LSx engine with vacuum leak and my truck has none of those symptoms: rough idle, runs rich, drivability problems. Before I installed the above components I had Charlie Wheatly update my tune accordingly. I am wondering if there could be an issue with the tune itself. Like I said before I do not know what to do next...

 

Well, if it isn't actually running lean and there aren't any vacuum or air leaks, sounds like the tune just needs a little tweaking...sometimes it's hard to get it spot on for a mod like this through the mail

 

What size injectors did you tell him? TBSS injectors are 36lb so your tune is most likely set for 36lb injectors. If you intake came from a non TBSS like a 08 up flex fuel 5.3 then your injectors are actually 32lb and thats your problem. Ask me how I know

 

I would talk with charlie and see what he says... Maybe it is really running lean...

And I'm glad to here you say it actually gained so I won't be wasting money... Where did you get żour xlink ?

 

X-link came from Torquerush.com. I think it was $220 shipped. Came in about (1) week.