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Old Aug 16, 2014 | 09:36 PM
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Question Diagnostic Reading Help

Apologies if this is the wrong area for this, or it is covered elsewhere. I am hoping someone with some more experience with these numbers might be able to interpret them for me. (See attached screenshots.)

There are no trouble codes. The only symptoms are a less than smooth idle, and poor city or mixed MPG (14 always). I'd been thinking that idle was high, as the factory gauge points to about 900 RPM in park, and around 800 RPM in gear. It looks like those actual numbers are 650 and 550, which may explain the subtle idle vibrations. All these numbers were grabbed while in drive in the driveway, engine hot. I also noticed that the voltage drops from a healthy 13.5 to 12.3 with the A/C on MAX, fans @4. I think that is mostly due to the heavy draw of the blower motor for the vent fans, and perhaps low output from the alternator at those RPMs (voltage goes up as soon as I start moving).

The alternator is new, as is the IAC valve, plugs, wires, cats, O2 sensors, PCV hoses and PCV valve, plus other things I've surely left out. Still, I just crossed 200K mi. Maybe I'll get lucky and there will be an easy fix. Thanks in advance for any help!
Attached Thumbnails Diagnostic Reading Help-wp_ss_20140816_0002.jpg   Diagnostic Reading Help-wp_ss_20140816_0003.jpg   Diagnostic Reading Help-wp_ss_20140816_0005.jpg   Diagnostic Reading Help-wp_ss_20140816_0004.jpg   Diagnostic Reading Help-wp_ss_20140816_0006.jpg  

Diagnostic Reading Help-wp_ss_20140816_0007.jpg   Diagnostic Reading Help-wp_ss_20140816_0008.jpg  
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