Autotap

I finally broke down and bought the AutoTap Express. There's a special deal
till 12/20 for $50 off.
Check out www.autotap.com
If they don't have it on the website still, use coupon code GR8DEAL

Comes out to $99 plus shipping.
OBDII to USB adaptor, software and runs on a laptop (computer not included).

Oppie

 

Got the unit yesterday. A little odd that the engine has to be running to
connect between OBDII and the laptop computer. Haven't tried key in the run
position but engine not turning.

No diagnostic codes were showing but the engine was not running smoothly and
the traction control had shut down. Traction control turns off when engine
is not running correctly.

Found that the coolant temperature was only about 150 which is too low. This
compares with a unusually low heater discharge temperature. I tend to
believe the CTS and will replace the thermostat. Also saw the bank 2 short
term fuel trim wildly fluctuating. This is likely a bad O2 sensor or a
vacuum leak. Sure enough, I found a cracked vacuum hose. Fixed the hose,
reset the ECU; engine runs better and traction control is active again.

Probably the reason that no DTCs were set is that the engine didn't get hot
enough to validate the codes. Many of the codes are set only when several
conditions are satisfied like the engine is at operating temperature. This
avoids phantom codes that might pop up on cold start.

The AutoTap Express device only diagnoses the engine. Will not show any data
for the other modules (Transmission control, body control). Haven't
confirmed that it will at least display codes from other modules.

Oppie