Emissions fail questions

[Budiceman]

Sorry if this post is long but want to include all info so I cant get HELP. Started with Evap emissions system code and CEL on. Replaced purge valve solenoid and hose to canister and disconnected battery. CEL went off and has not come back on. No codes on scanner and have driven and driven but still wont pass Readiness for cat, O2 sensor and O2 sensor heater. Last time I went for test noticed that odometer is not working but speedometer is. Found post that said thermostat replacement because of engine not reaching temp...my temp gauge was never going past a little over the "c" no matter how long I let it idle. Just replaced Tstat and now temp gauge goes up drove around a while but still fail. Should I have disconnected battery when doing Tstat and then drive or can my odometer not working affect computer not "thinking" miles are put on to reset the drive cycle. Already have 2 very expensive tickets for expired tags so I appreciate any help.

 

[Budiceman]

Update

Disconnected battery and drove some more maybe close to 100 miles. Tough to tell with odometer not working. Back to emissions. They just check readiness for me now been there so many times. Fail again but now 4 things..catalyst, O2, O2 heater and EGR. ANY HELP?!!!! appreciated.

 

[albi1cnobi1]

The catalyst was probably the t-stat, disco the battery and that should clear. The O2 heater is either a bad connector or a bad O2. O2 sensors don't work well at low temps so they have heaters to bring them up to temp faster. The EGR is most likely just clogged with carbon. If it's been running cool for a while that'll do it.