If you have an Android phone or tablet, for about $30ish you can get a bluetooth OBDII plug and the app Torque - which gives realtime data on the systems in your vehicle, along with any possible trouble codes or readiness indicators. You can even use it for a speedometer, tach, voltmeter, etc. It's pretty well rounded.
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1988 9C1 - Modified LM1 @ 275HP/350TQ - TH700R4 - 3.08 8.5" Disc Rear - see it at
http://www.silicon212.org/9c1!
2005 Crown Vic P71 - former AZ DPS - 4.6 liters of pure creamy slothness!
1967 El Camino L79/M20 old school asphalt raper
Remember - a government that is strong enough to give you everything you need, is also strong enough to take everything you have.