[tazman2]

So shortly after I got the car I got a downstream o2 error. Bought a oem and changed a bad fuse and o2 and no more code in over 2k miles. But about 1000 miles ago I got a p0455 randomly here and there every 200 or so miles. Changed the cap to a stant and it turned on even earlier (about 35 miles) so put the original back and same thing about every 150-200 miles. Bought a oem last week from rockauto and its still kicking on every 200 or so miles. Checked vacuum hoses, etc. under the hood that I can see and nothing "fell" off. I don't smell fuel soooooo I dunno. Also when this started my mileage went from 30/31 to 25 and now that its cooler outside 23.8! =( [thumbd]

PS: This is for a 2000 ZX3 ATX!

 

[BC_ZX3]

Other things to check listed below. EVAP canister is under the car by the fuel tank.

P0455 - EVAP Control System Leak Detected (No Purge Flow or Large Leak)
The PCM monitors the complete EVAP control system for no purge flow, the presence of a large fuel vapor leak or multiple small fuel vapor leaks. The system failure occurs when no purge flow (attributed to fuel vapor blockages or restrictions), a large fuel vapor leak or multiple fuel vapor leaks are detected by the EVAP running loss monitor test with the engine running (but not at idle).
Causes:
After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
Disconnected or cracked fuel EVAP canister tube, EVAP canister purge outlet tube or EVAP return tube
EVAP canister purge valve stuck closed
Damaged EVAP canister
Damaged or missing fuel filler cap
Insufficient fuel filler cap installation
Loose fuel vapor hose/tube connections to EVAP system components
Blockages or restrictions in fuel vapor hoses/tubes (items also listed under disconnections or cracks)
Fuel vapor control valve tube assembly or fuel vapor vent valve assembly blocked
Canister vent (CV) solenoid stuck open
Mechanically inoperative fuel tank pressure (FTP) sensor
Check for audible vacuum noise or significant fuel odor in the engine compartment or near the EVAP canister and fuel tank.