Nuke

You'll be happy to know that you're in good company. This happens quite often.

2010Knight_Ryder

Returned the car to stock tune, drove for about 300 miles (or complete drive cycle). Check engine light came on stating "Catalyst exceeding threshold" or something along those lines. I cleared the code and drove the car another 50 miles and the car passed inspection.

adj86

@Knight Ryder

Are those cats that come with the Kooks listed as high flow? I have Boost Brothers longtubes with Thunderbolt High Flow cats and I have the P0420 and P0430 for the catalyst operating below threshold, on a stock tune with stock airbox and I can't pass emissions. Also what type of gas were you running during the testing? 93? This is really wearing me out.

adj86

@knight Ryder, clutch post man. Did the same thing you did today and I passed emissions after 3 tries.

TPony

Hey thanks, I just returned my stang to stock and completed the drive cycle. Scan tool shows all sensor at ready. Will take to station tomorrow we'll see how it goes.

2010Knight_Ryder

No prob guys, any time.

TPony

Well...it passed emissions, no problems. I went home and re-uploaded the tune again and presto, back to performance.

2007bluestang

My place just looks at the mileage and gives you a sticker Haha

adj86

Yep, I loved Mississippi's Inspection.

Me: Hey I need an inspection

Local Oil Change Guy: Cool, That'll be $5.

Me: Here you go (hands $5 bill to LOCG)

LOCG : Cool ($5 goes into pocket), here's your sticker.

Me: Thanks.

TPony

^ Amazing.