California and Stratified Stage 1 Tune

[RBYM]

Has anyone tuned their fiesta st in California with a stratified stage 1 tune and went back to stock tune using their accessport and passed a STAR CERTIFIED SMOG legally? My only mods currently are a Cobb drop in filter, cobb rmm, coilovers and wheels.

I want my car to pass smog legally year after year as long as I can revert back to stock tune and pass smog check and Star certified smog.

 

[Dialcaliper]

Yes, you can go back to stock (Stage 0) as long as you drive it for long enough to reset all the OBD system monitors, which you can verify in the Accessport.

You can also pass with Cobb Stage 1 or Stage 2 tunes, which are CARB approved and will pass the ECU check.

You will *not* pass with the Stratified tune loaded

 

[RBYM]

Yes, you can go back to stock (Stage 0) as long as you drive it for long enough to reset all the OBD system monitors, which you can verify in the Accessport.

You can also pass with Cobb Stage 1 or Stage 2 tunes, which are CARB approved and will pass the ECU check.

You will *not* pass with the Stratified tune loaded

Thank you.

 

[RBYM]

Yes, you can go back to stock (Stage 0) as long as you drive it for long enough to reset all the OBD system monitors, which you can verify in the Accessport.

You can also pass with Cobb Stage 1 or Stage 2 tunes, which are CARB approved and will pass the ECU check.

You will *not* pass with the Stratified tune loaded

How good are the Cobb stage 1 and 2 tunes? Will they damage the engine?

 

[Grsemky]

Yes, you can go back to stock (Stage 0) as long as you drive it for long enough to reset all the OBD system monitors, which you can verify in the Accessport.

You can also pass with Cobb Stage 1 or Stage 2 tunes, which are CARB approved and will pass the ECU check.

You will *not* pass with the Stratified tune loaded

He might be able to pass if he opted for the economy map with the tune

 

[Dialcaliper]

He might be able to pass if he opted for the economy map with the tune

He won’t pass the ECU checksum test California finally implemented as of Jan 2025 with a non-CARB approved tune.

The COBB tunes are decent but quite conservative and lack the refinement of better aftermarket tunes. You can also run them fairly safely on the eco-map even with a hybrid turbo, as long as you’re just driving casually and not pushing the car into boost

 

[RBYM]

He won’t pass the ECU checksum test California finally implemented as of Jan 2025 with a non-CARB approved tune.

The COBB tunes are decent but quite conservative and lack the refinement of better aftermarket tunes. You can also run them fairly safely on the eco-map even with a hybrid turbo, as long as you’re just driving casually and not pushing the car into boost

Can I get a stratified tune and then revert back to stock or Cobb tune to pass smog?

 

[Dialcaliper]

Can I get a stratified tune and then revert back to stock or Cobb tune to pass smog?

Yep. Load the Cobb tune and leave time to drive around with it until the readiness monitors are all checked off and you should be smog legal.

 

[RBYM]

Yep. Load the Cobb tune and leave time to drive around with it until the readiness monitors are all checked off and you should be smog legal.

Thank you!