swathdiver

Has anyone ever noticed a difference between the tune in a California car versus one with Federal emissions? For a GMT-900 with the 5.3, the Federal standard is GMXT05.3373 and the California standard is GMXT05.3381. Mileage and fuel use and emissions ratings are the same according to Uncle Sam but the California cars get a boost in their smog rating from 5 to 6.

About four years ago there was no physical differences between the cats but these days they do indeed appear to be physically different.

If someone is curious to compare them, I do have my original tune saved in EFILive! from BlackBear which is California emissions. Why they sent a California emissions car to a Pennsylvania dealer is beyond me.

wretched73

iTrader: (1)

IIRC decades back Cali cars had 4 cats when every other car had 2. A friend had a Camry from Cali and it had double cats. I think 3rd gen camaros were the same but it has been way to long since I've messed with that stuff.

dantheman1540

I wonder if they have lean cruise activated on the Cali cars. IIRC the lean cruise function was mostly active in Australia or something weird like that.

1FastBrick

iTrader: (17)

It's not active but its usually in the background and can be activated with the right software.


As far as I know with California certified vehicles, It usually jut means they paid Komifornia Extra money to certify it. In some cases like on the GMT 800 they had an EGR and Air Injection installed on the early trucks. Some times on different vehicles they may add an additional catalytic convertor. Most of the newer cars though are pretty much the same. This is Why Donald J Trump was trying to end to the Extra Certification mandated by California on car makers. The Federal certification should be the national standard that every one has agreed on. States should not impose or mandate there own restrictions.

arthursc2

iTrader: (5)

Meanwhile, more states are pledging to adopt CA standards. Like NM and MN. Huh

I have a CA compliant MR2, it had a pre-cat in the manifold and a yuge cat after it. Had

68Formula

I doubt it unless they ran air injection to reduce the increase in NOx a lean mixture would generate.

swathdiver

From what I've read, Lean Cruise was not used on Gen IV engines, it was replaced by AFM and VVT. I had not heard of Lean Cruise until this thread. Interesting stuff and sadly political.