How Much Should I Spend On A OBD Code Reader ?


Thread starter
Mar 30, 2015
Lake Havasu City, Arizona
It turned out to be a P0456 Code. "Evaporative Emission System Small Leak Detected".

"Diagnostic trouble code (DTC) P0456 stands for “Evaporative Emission System (EVAP) Small Leak Detected.” Your car’s computer will set this code when it determines that there’s a minor leak somewhere in the evaporative emissions control (EVAP) system".

It basically doesn't mean crap. We don't require having our vehicles emission tested in this county, so I don't have to worry about failing any type of emission tests.

So I cleared it, and no more MIL "Check Engine" light.

So..... I'm glad I bought the reader. It was worth the money. It's easy to run. You basically just plug it in, then cursor around until you find what you want to do, then hit, "Enter". If you get confused, or miss something, you just hit the "Back" button. Not too much different than screwing around with the remote control on your TV.


Nov 6, 2017
When the, "Why should I buy a code reader when the local auto parts shop offers reading service" threads come 'round I often wonder how many trips (time, fuel, aggro) will it take to pay for a reader.

Plus, when you get multiple codes and clear 'em all, it can really help to have a code reader handy to track return codes.

After a neighbor caused a problem (which required driving time to clear completely) I needed to monitor the ever expanding gap between recurrences. He overfilled his oil and driving was needed to clear the cat. Each time I drove it the CEL took longer and longer to return. Finally, it didn't return. Having a code reader with me let me accurately track the CEL and easily saved 20 trips to some store.

And remember, sometimes shops have the cheapest readers imaginable.
An Advance I went to had no reader because it had been stolen and the proprietor wouldn't spring for another.
My wife used to manage a "luxury limousine" fleet and some of the readers at AutoZone wouldn't get anything off Mercedes even with a CEL present.

I sometimes glance at their parking lot readers and they can range from $20 pocket readers to fairly nice Innovas.

So yeah, relying on the corporate parts stores is a crapshoot at best.
Jan 2, 2004
I have a Carista and a ThinkDiag 2. The latter is a pro-grade bidirectional tool that uses your phone(ideally Android if you’re planning to work on Euro stuff) that is nearly but not dead-on the same as a Launch scan tool. The former is great for quick code scans.

Avoid any cheap Chinese dongles with a counterfeit ELM327. Also, if you have a newer Mopar with SGW, you might be SOL.