ERROR CODES READ:
1. P0300 Random Misfire Detected
2. P1443 EVAP Canister Purge System Malfunction
3. P0402 Excessive EGR Flow Detected
4. P1401 DPFE Sensor Circuit High Input
5. P0420 Catalyst Efficiency Below Normal (Bank 1)
6. P1151 Lack of HO2S-21 Switching, HO2S Signal Low Input
7. P0174 Bank 2 Combustion Too Lean

 

sounds like you may have a stuck open egr valve, start the car, and let it idle, after 10 min or so carefully check to see if the egr valve is hot. i dont mean warm, i mean HOT. if it is it is stuck open. this can be caused by it receiving vacuum when its not supposed to, or its physically stuck, or your cats are plugged so bad that the back pressure is forcing it open. my money is on the cats as the codes say they are already not working. without being there this over the forum process of diag may take weeks, i would spend the money and take it to a QUALITY technician for diag, it will be cheaper in the long run.

 

Ok, because AZ printout said suggested fix was fuel injectors, and the guy said a tuneup instead, so I'll check that and get back to ya..

 

yeah nooo...shop looking to start with something and say "oops, that didn't fix it, it could be this (throw more money at it and see what happens" Find another shop.

 

Couldn't a faulty DPFE sensor cause the EGR to be stuck open and thus cause some if not most of his other problems? I'm just curious.

 

no, the dpfe sensor is only there to let the pcm know that the valve is actually flowing, its part of the federally mandated checks to make sure emissions equipment is operational, per OBD2 guidelines. before, in an OBD1 vehicle, the pcm didnt know and was unable to tell if the EGR valve was actually functioning