hey brothers need your help.today i tried to pass emission test but i failed.i have an 8 but with 9 turbo(untuned yet),run on E85,all bolt ons minus intake manifold.got 3 codes p 0134,0171 and 0403. i think 0171 system too lean but i have wide band and i know i never run/idle too lean,code 0134 bad front o2 sensor but i changed it like 6 months ago.now code 0403 that i done know.
2 years ago i had same modifications minus 9 turbo and i was running on 93 octane and i passed.i live in Illinois.what do you guys think?

 

P0134 - Could be a few other things besides a bad O2. Could be leaky Throttle body, could be egr issues.

P0171 - Could be a leak somewhere in your intake plumbing , IC plumbing. I think I go this code after a bad vacuum leak.

P0403 - EGR issues.

Noticing a theme here. Do you still have the EGR system in place?

 

After searching for a few I think this thread might help you.

https://www.evolutionm.net/forums/la...401-arg-2.html I think your EGR system is the culprit. And possibly a bad throttle body gasket.

 

thanks man for quick reply.yeah i still have egr system in place.the funny thing is i have no cel.as for the leaks i have an appt next week with Boostin for dyno tune and the procedure starts with boost leak test.

 

did dyno tune recently and tuner found nothing wrong witg either codes.he tuned the car and took care of the codes.and yes,he did boost leak test,it was solid.