1998 GMC Yukon Q&A

1998 GMC Yukon Question: failed emmissions codes

Does anyone out there know what these codes mean? The emmissions place did not know?? P0155 and P0300? Trying to get an idea b4 I go to mechanic so they tell me the truth! Thanks! -
Answer 1
Here is some info abou both codes: http://repairpal.com/OBD-Code-P0135-and-P0155 http://repairpal.com/OBD-Code-P0300 -