Pulling Codes?

[miksax]

My 91 Hatch has 156k miles. I doesn't run bad, but I know it is getting tired, doesn't have the power it should, and doesn't run as smooth as it could. It is stock except for o/r H Pipe, 2 chamber mufflers, cold air intake, timing boost, and a king cobra clutch.

I am trying to get it back to where it should be, but I'd hate to spend a lot of money replacing stuff that may not have a positive impact. I have heard that pulling the codes can be beneficial. My check engine light doesn't come on, can these codes still tell me what may be happening?

If so, how do I get these codes? Do shops have the tools to hook up to my diagnostic connection? Or is this not an appropriate first step?

 

[fastford91]

you can go by a code puller for about 30$ at your local auto parts store! there is away to pull the codes without a code reader ! you can do it with a paper clip! im sure that way will be posted for you soon! i prefer to buy the proper tools when needed! that way you aways have them! but if you cant afford the 30$ the paper clip method will work fine! just not my cup of tea! just because your check engine light isn't on doesnt mean there arnt any codes there! they can still be present without the light being on! dumping the codes would be a good way to start! if you buy the code reader it will also come with a book to tell you what the codes are !! if not you'll have to post your codes on here and someone with a book will have to post for you what the codes mean!! hope this helps you!

 

[miksax]

Do you know the name of the code puller? or any brand I should look for?

 

[fastford91]

doesnt matter the brand as long as it will work with the make and year of your car! you can spend 200$ or 30$ either way they all tell you the same thing!

 

[jrichker]

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See http://www.troublecodes.net/Ford/

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/pc-7208-90-equus-digital-ford-code-reader-3145.aspx – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.

 

[TrickFlowd]

This thread helps me out alot too! Thanks again jrichker!