[hatzie]

People seem to think that OBD II scanners are super expensive...
You can build a 7" Android tablet based OBD II scanner for $135 or a 5" phone based scanner for $105.

The 8gb Amazon Fire 7 tablet is $50. You can get a 5" Android cell phone at Wal Mart for $20-$30. No cellular data plan needed on either. The build quality of the Fire Tablets is much better than the ElCheepo cell phones. You don't need to connect either of them to anything but WiFi and you only need that long enough to connect to Google Play or the Amazon app store and download Torque. You can do that on free WiFi. I use ElCheepo brand $20 Walmart Android phones for Bluetooth DRO displays on my Lathe and my Milling machines and they're not connected to any cell network at all nor have they ever been.

Software cost? Torque is free... Torque Pro was under $5 IIRC. Not super pricey for the full version and it's a lifetime license.

You don't need GMLAN CAN capability so you can find a good old fashioned J1962 (OBDII) bluetooth interface. It's the most expensive part of the tool. You can buy the cheap Chinese ones that might work or just get an OBDLINK MX for $80 on Amazon that will work every time you plug it in and won't screw up your PCM.

If you figure you can't afford to buy one think about how much it'll cost to pay to have the vehicle diagnosed or to swap a bunch of parts you don't need to replace til you fix whatever is causing the problem.