please help,have a 2000 imprz outbk sport.wcodes p0301,p0302 still after complete tune up does it after 5-10 mins drive time runs like poop and smells like sulphur

Have you had your catalytic converter tested for flow?

does the CEL flash? (1 and 2 share a coil , could be bad but ....)

 

what was done in the tune-up?

 

miles and history, condition of car ????

Edited June 9, 201510 yr by 1 Lucky Texan

Unplug and pull out the pre-cat O2 sensor, see if it makes a difference. Or, if your flange is before the cat, you can do it there too. Make sure to unplug both o2 sensors when doing this test. It will help see if you have a plugged exhaust.