What is the Best OBD-II scan tool

Who or what is the best OBD-II scan tool?

I would like one that can display real time data on my laptop, and that is compatible with Jeep and Fords for collecting and displaying sensor data.
DTC only scanners are just too limiting for diagnostics.

I bought the $99 one at Wallyworld, thinking about taking back and getting something better that can display real time data on the scanner or a laptop.

Since my wifes Nissan Frontier popped the CEL light on, I've been looking at them myself. The light went away on its own so I haven't been in a big hurry. Here what I came up with so far.

If you want nice with laptop hookup, both the AutoTap and Auto Enginuity stuff is a couple hundred but looks very capable and tons of features. Going to a laptop setup gives you some upgradability and usually the ability to record live data, pull codes from and talk to the other computers in the vehicle, such as the tranny or body computer. I saw a few other laptop connection setups for $100-$120 range but didn't look too hard at the features. Some of them were OBD protocol specific and didn't do all vehicles unless you bought the extra cables..

Most of the tools out there can talk to the 4 common OBDII protocols. A newer protocol (same connector) is CAN which is being used on many vehicles since 2003. The list of CAN vehicles includes the Jeep Grands and a bunch of Fords. Depending on what you have, you should make sure the reader can talk CAN as well. Also it seems Audi, VW, and some BMWs require a unique reader as they are still non-standard.

Here's what I think I'm buying for $42 plus shipping. It does the basic reading and reset, shows what the code means, and can display live data. It doesn't do CAN, but I don't have a vehicle that needs it. It's korean made, but has decent reviews.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=110201101942


This one does do CAN and has a few more features for $99.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=110200165876

Here's a couple of links to help determine what OBD protocol your reader needs to support. http://www.scantool.net/searchCV.html http://www.scantool.net/support/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=3

Another option is buying just the adapter and using one of the free open source software packages.
http://www.scantool.net/products/index.php?cPath=8_6

genisys by otc/spx. we use it at school. the best ive ever seen or used.

genisysotc.com

Consider this...pick up a used autoxray scanner off of ebay....and a 10 MHZ or higher, used oscilloscope ...I did it with little effort about a year ago, and total cost was less than $200 including shipping...you spend a little time learning how to use a scope, and will have that knowledge for a lifetime...plus a scanner for the easy stuff...There is nothing like clipping your wire piercing scope probe on the Crank Position Sensor signal line that goes to your PCM to "see" if it is doing it's job, while your engine cranks over but won't start...Years ago, oscilloscopes woud cost big bucks... (thousand's), but now you can pick them up on Ebay for chump change. . .(I got a good two channel unit for $55 plus shipping) ..if that doesn't float your boat, buy a Digital Volt Meter with a RS232 output to connect to you laptop serial port, and the free software they give you with the purchase of the meter will turn your laptop into a cheap oscilloscope..cost less than $200... you won't use the scope that often...but a good DMM with RS232 output is really worth the investment....here is a unit I recommend in fact...$100 plus shipping...

http://www.multimeterwarehouse.com/MS8220Rf.htm

McQue

I highly agree on the multimeter and scope skills. You can do quite a bit with a $20 meter and some basic troubleshooting skills. I also have an older 100 MHz scope which I've occasionally drug out to the driveway. Very handy to look at the ABS and CPS sensors. Last time I used the scope on the car was to settle a debate whether adding a small capacitor across the CPS sensor would boost the signal. Turns out it would but too high of a cap caused the signal to distort enough the engine would start stumbling.

What's the sampling rate of the pc-connected multimeter? Is it fast enough to be useful as a scope?

www.aeswave.com.

They've got PalmOS-based and PC-based stuff. I've not used it myself (yet,) but they make a good noise, and I likely will once I have the dosh (since we bought the 2005 Verona for her. Before, I just didn't need OBD-II capability...)