I apologize if this is old news but I'm stumped. My 99 Blazer seems to run good but has no power. Hills are a major challenge. I currently have P0101, P0404 and P0452 alarm codes. I have, within the past year, replaced the fuel pump and the fuel filter. The problem seems to have come on in the past two weeks. With the help of the auto parts store I'm looking at the ECM, the fuel pump again or the catalytic converter. I can't afford to start replacing things at random so I'm looking for any help I can get. Thank You!!

 

I would suspect the cat.

 

P0101 Evaporative Emission Control System Pressure Sensor Low Input, P0404 Exhaust Gas Recirculation Circuit Range/Performance, P0101 MAF sensor. Get those fixed then go through your other options as to what it could be. I would start with the easiest and cheapest things first like cap and rotor, plugs and wires etc. I also would suggest the cat because a plugged cat will do what you are talking about, but thats not A cheap fix your looking at 250-300 bucks to have it replaced

 

Thanks for the help! I finally located my problem. I got to thinking about the catalytic converter and with a several well aimed shots with a hammer to the converter, my Blazer is running good again and all my check engine alerts are gone. My big question now is whether to replace the converter or bypass it?

 

I would look into replacing it for inspection if your inspection is good run it for awhile with it bypassed but save your money to get one before your next inspection .