Engine diagnostic code scanner

Also, you will see a wide price range in scanners. The most basic will let you see and clear a code. As you go up in price and features you will be able to get more information from the system. I have one that I about at Oriellys for about $150.00 I give data as you are driving about what is going on in the system such as o2 sensor, map sensor tps and on and on.

It even went into more complex stuff that I'm getting rusty on and wont describe accurately. Fuel counts etc ??????

One example

AND depending on what you buy be sure it covers your year. obd2 is universal but my old Actron will only go up to the year that it was built in. Obviously it was impossible for them to build into the future but there are probably testers out there for sale that are too old for your vehicle.

There are many different scanners/reset tools on the market. Codes can be found on the internet but remember that if you get a code for example say a heated o2 sensor. It doesn't always mean the sensor is bad, it can be something else in the circuit. A common code was for o2 sensors and one fix was to remove and clean the connectors/relays in the power center as the ecm was reading an incorrect resistance in the circuit.

It doesn't always mean you can fix the problem but a reader is very handy and with a little code searching you can at least have a better understanding of what is going on even if you do take it to a shop.

This is just one example of sites with codes.

Codes

Edit:
as jrs says, a common code is for loose gas caps but it again can be anywhere in that system. Emmision systems not only monitor and adjust what is coming out the tail pipe but also control smog from fuel evaporating into the atmosphere.

So you could have a loose filler neck hose or a cracked or rotted hose somewhere else. If you are hands on you can start snooping around, fix the hose, reset the ecm (erase the code), drive it again and see if code returns.

It's common to take a vehicle in multiple times for codes like that if they dont have the equipment to properly trouble shoot it. The equipment in this case would be the machine to "smoke" the system. It feeds a smoke into the system and the tech can see where the leak is.

You dont have the equipment either but with the scan tool and a visual inspection you may be able to fix it for just the price of a $2.00 connector elbow.

I agree with locster. Plus, it is worth the price just to know a little bit about what is likely to be the problem, even if you still intend to take your vehicle somewhere to have the work done 95% of the time.

My personal experience has not been that good, but I am probably the exception. I had an analyzer specifically targeted for certain year Ford products, including my 1989 Mustang. Long story short, it gave bad info.

More recent experience with my Cummins' diesel was that a emission service code did not show up even though I was getting a warning on the dashboard that something was wrong. But the emission service code did show up at the dealer. Naturally they have the best equipment.

My son had a check engine light problem on his Pontiac, and it was attributed to the infamous loose gas cap. Well, you needed to put the car on a hoist to figure out that the problem was not with the cap but with the filler tube itself. So this type analyzer pretty much told him about the problem, and that it was not major, but the exact root cause of the problem took some snooping around anyway.

I see the the greatest values as being that when you get the check engine light warning you can have some idea whether or not there is a really serious problem lurking around the corner and it gives a person a chance to do some homework on the issue even if they are going to take their vehicle to a professional anyway.

You can get an OBD II Bluetooth scanner from Amazon. Plug it in your OBD port and read everything off of your smartphone. No need to decipher any codes. Works on multiple makes and models. All for a fifth of the price of an actual scan tool from an auto parts store.

Consider the ScanGaugeII. It not only reads the codes but also gives you many engine and transmission data instantly. It does cost more than a plain OBDII reader.
Codes are readily available on the internet.