runs normal a/f at idle but very LEAN when driving. no coolant guage reading

[DSMTyson]

Yesterday i was driving home and all of a sudden, while crusing, my a/f ratios went from oscillating at 15.6:1-17:1, to staying at 17.5:1 and LEANER sometimes not even reading on my AEM wideband and just staying on the last red bar. is going on.

I woke up this morning, changed the o2 sensor, Started her up and it still runs just as lean. I'm going to hook up link in a minute and run a log, and post it up.

I thought it was a bad coolant temp sensor but wouldnt that make me run rich?

My log is further down the page when i replied to Colt4G63

 

[Colt4G63 also]

Wiggle the plug on the single wire temp sensor. How is the A/F ratio with the new O2 sensor?

 

[DSMTyson]

a/f ratios are still the same. I'll see if wiggling the wire on the cts will work, but i doubt it.

 

[Colt4G63 also]

The CTS for the gauge is not the same CTS that the ECU reads.

 

[DSMTyson]

Oh, i see. well when i hook up my datalogger(link), if the ecu is reading coolant temps then it should show up on there.

heres the log. looks like i have a boost leak. what do ya'll think?

logs