Hello everyone!


Since about 18 moths ago, from time to time, my Check Engine Light is set off by following fault codes:


16555 - Fuel Trim; Bank 1: System Too Lean; P0171 -35-10- -- Intermittent.


This error usually appears with another fault code simultaneously:


17831 - Secondary Air Injection System; Bank 1: Insufficient Flow; P1423 -35-00-,


However, few days ago 16555 appeared with 17700 (instead of 17831).


The vehicle works normally, it shows no signs of wrong engine work, no signs of power loss, no engine temperature fluctuations (engine heats up to 90 C always after the same amount of time and maintains this temperature). Nevertheless, I am worried about Check Engine Light being set off regulary by the same set of fault codes. Usually, after clearing the codes, there was about one or two months long inverval between incidents, but since lately my car drives about 40 km a day, fault codes appear every few days and it is irritating.


Car is equipped with sequential LPG installation, also, an engine overhaul (piston rings replacement) was performed.


Thank you very much in advance for your help!