Hey guys, I am trying to convert back from a 2bar/80e tune to the stock maf/80e tune that has had a segment swap applied to it. I am running stock ls2 32lb injectors, not the 24s that came with the truck.

Everything works perfectly with the 2bar tune, but when I do a write entire using the maf/80e tune and switch the MAP sensors the truck will start and idle but is extremely lean (wb shows 18ish), and if I force it into closed loop the trims go to +50 and its still slightly lean around 15. I thought the injector data might be off but they are exactly the same, both tunes have the 32lb injector data...any help would be appreciated.

Here are the files i attached on the hpt forum

thanks

 

Sounds like the injectors may really be 24#'ers.

 

Have you changed the truck at all? Or are you trying to change from SD to MAF on your current setup?

 

Then why do they work so well on 32lb injector data on the 2bar tune? The part number on them says they are stock ls2 injectors.

The only thing I change on the truck between tunes is the map sensor back to the stock one.

 

Sounds like your VE take is off. I would try to correct your table, and if you aren't happy I would go to the SD tutorial in the help section and reverse everything.

 

The two tunes that you posted on HPTuners forum are vastly different. There is much more different than just reenabling the MAF. Are you still running roced induction?

 

No, its a stock vehicle now except for the 80e swap. The only difference between the maf/80e tune and a stock tune for a 5.3 truck should be the spark table, 80e segment swap, TM stuff, and injector data.

I compared the tune I was trying to use to one I had before I did my cam (ie, stock) and the ve table is within 4% so I dont think thats the issue since trims are +50%

 

If you tuned the VE table with the incorrect injector data, you can still get it dialed in. Of course this would never work on a mailorder, but if you were doing it yourself, I could see you adjusting fuel on the VE table until it ran well. Just a thought. Easy enough to try-change the IFR tables to 24# settings and flash it. See what happens, nothing to lose.

I had a truck in the shop last week, fuel trims were +50% on bank one only. It had a bad O2 sensor(B1 S1).

 

Ill give it a try later for ***** and giggles I guess.

I would suspect O2s as well if my wideband wasnt telling me lean and they work fine on another tune...

 

Wasn't your 2-bar SD tune running in open loop? If so, you weren't using the O2's at all.