I bought a 2000 S4 6 speed in September, and ever since have been on this forum nonstop. The car is stock besides Stasis Track Sports and JHM shifter. But anyways this is my first post. I have a check engine light on that I just check for codes. The codes are

17861 Exhaust Gas Temp Sensor 1 (G235): Open or Short to Plus P1453 - 35-10 -- Intermittent

16805 - Shareware - P0421

16815 - Shareware -P0431

Ok, so after searching the forum, I have found that most likely I need to replace one of my EGT sensor and that my cats are bad (time for piggies?).
My Question is, is there another issue that could be causing these codes. I thought it would be strange that both P0421 and P0431 would appear at the same time. I just dont want to replace parts when it is not the real issue.

Also, Is EGT sensor 1 the passenger or drivers side?

It may also be good to tell you that the other day the car was jumpy when pressing the accelerator and letting go of the accelerator sporadically which could be a sign of a bad EGT sensor it think.

Any help on next steps here would be most appreciated.

Ryan

 

You have been here non stop, but this is your first post?

I would change out the EGT & go from there, my bet is you have other problems, & yes, both cats can be bad, & this can also cause a EGT fault.

 

P1435 is your problem ( secondary air injection (APR) short to ground ) possible fix = wiring short to ground, AIR pump relay

 

thanks for all your help so far.

Ryan