I recently got my 01 blazers 4.3 rebuilt and ditched the whole A/C system because some backyard mechanic tried to fix it way before I got it. I deleted the A/C with a dorman A/C bypass pulley and pulled the A/C relay and fuse I just tucked the A/C connectors back and zipped tied them to the rest of the harness. Only problem is I have the check engine light on now. I’ve read that misfires are common on these but I replaced the cap and rotor so I don’t think it’s the ignition system throwing the code. Any help before I go and buy a scanner would be much appreciated.

 

Can’t do much without the codes. An auto parts store can pull them for you but you can get better capability than them for a modest investment. I can’t think of any reason why the AC delete would cause a code, I don’t think the system monitors the compressor circuit.

George

 

Thank you for the reply. I went out and a scanner and ran the code today it out to be a P0418 secondary air injection system relay. I thought I would have to replace the air injection system but I did some further research and I believe that I’m just going to have to replace the relay. It’s a $25 part at autozone that I’m going to get tomorrow before work.

 

There is more than one possibility:

https://www.obd-codes.com/p0418

If you want to rule out the relay, swap with another identical known good relay from the fuse box if available.

George