2003 Tahoe 4x4 Z71 5.3 Vortec Flex Fuel. ODB 2 codes P0300 (Multiple Misfires) and P0134 (O2 Sensor low or no voltage) 56,000 miles, regular unleaded fuel.
On changing spark plugs, discovered that all plugs on passenger side had good burn but all 4 on driver's side were carboned up. Seems like mix is too rich on driver's side. Where is the problem? Common factor to those cylinders is fuel rail. Is it a fuel regulator or some other air/fuel mix valve problem?
No other codes on reader occur and it happens intermittently that the milage drops to ridiculous, engine runs rough, and Check Engine light starts a flashing.
have the same problem?
Monday, January 9th, 2006 AT 1:09 PM