408 Stepside 01

I changed my buddies cam in his ss camaro. And i had no problem tuning L-Trims with his air mass sensor. However on my tuck no mater what i do with the injector flow rate table and the MAF table. It doesnt seem to change what so ever. It goes a little lower at first then proceeds to clim to 25. I also tried to change my fuel psi at idle, while watching my short fuel trims. Nothing changed. Any idea why it wont change. By the way if it makes a difference i have a electronic tb from the factory.

FrankSS

iTrader: (18)

i think i changed my VE tables and a little bit on the IFR tables to bring mine down from around +10. maybe your O2 sensors are shot?

XLR8NSS

iTrader: (4)

The first thing that comes to mind is that you have an air leak someplace, either at the intake after the MAF or on the exhaust before or close to the O2 sensor.

Is your PCV system still stock? It is a closed system normally so if you have a breather on it your trims will show a lean condition.

My bet is you have an air leak someplace.

felton316

Sounds like an air leak

408 Stepside 01

thanks i will check it out.

SmaknaSS

iTrader: (1)

After I changed out my cam my L-trims went to the rail(+25%), I changed out my O2 sensors and all was fine after that. I think the oil and coolent messed up my O2 sensors after removing the heads. But all's fine now.

Cal

iTrader: (1)

You can use an unlit propane torch to find intake leaks; engine will rev up when you blow propane on the offending area.

408 Stepside 01

My 02's are probably bad. I know with my last motor i kept hiting the grams per/sec limit and basicly torched off one of my 02's. I have sinse replaced one 02 and the other one is still original. My L-trims are also always differnt from one another until they get to 25. How ever i do know that my intake might have a small leak through the egr tube. Not to sure.

FrankSS

iTrader: (18)

get some starter fluid and spray around the intake to see where your leak is, the engine will rev...