engine miss

2000 CHEVROLET BLAZER

138,000 MILES • 6 CYL • 4WD • AUTOMATIC

EARLJOEBOB

MEMBER
1 POST
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I have a 2000 blazer, running rough and setting a P0300 code and CEL starts flashing. This happened right after getting gas, so I took a sample at the fuel filter and it seems to have some water in it. It has also had a P0420 code that I have been trying to figure out since last fall. I thought my cat was plugged, so I removed the O2 sensors to relieve the back pressure but it did not help. I have checked the compression, plugs, cap, rotor and fuel pressure. The ignition coil looked like it was burned so I replaced it still nothing. I don't know what to do next. Please help!
Thanks,

May 31, 2011 at 3:48 AM

WRENCHTECH

CAR REPAIR CONTRIBUTOR
20,761 POSTS

If you have any reason to believe you have bad gas, then you have to get that resolved immediately. Remove the tank to drain it and replace the filter. The PO420 is just a bad Catalytic Converter, not necessarily plugged up, just not doing the job it was designed to do.

May 31, 2011 at 12:00 PM

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