check engine light after driving, but not idling?

[fox racer]

if i start my car and let it sit, the check engie light wont come on. but if i drive around for a while, it will come on. then if i kill it and start it it goes away. any ideas? i was told when i bought the car i needed a new map sensor, could this be the problem?

 

[stang22]

Your best bet would be to hook a code reader up to the EEC and check what code it is actually pulling instead of trying to guess. AutoZone will check your codes for free if you do not have a tester.

Tim

 

[Stang8URMPRT]

They "do it" for free after they take you in the back room and have their way with you.

 

[jrichker]

Dump the codes and see what the computer says is wrong…

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.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

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.

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 Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $33.

 

[stang22]

They "do it" for free after they take you in the back room and have their way with you.

I have heard that about the Autozones in Daytona! Someone said they saw a guy in a silver LX pull in and went to the back for hours!!!


Seriously though, jrichker is the man!

Tim

 

[Stang8URMPRT]

I have heard that about the Autozones in Daytona! Someone said they saw a guy in a silver LX pull in and went to the back for hours!!!


Seriously though, jrichker is the man!

Tim

Ya gotta do what ya gotta do ya know!! It's ok, the manager lady was Carmen Electra!

 

[Mustang5L5]

I bet it's an EGR code.

It's either clogged or not functioning properly

 

[90mustangGT]

Ya gotta do what ya gotta do ya know!! It's ok, the manager lady was Carmen Electra!

It's amazing how one day they are famous, next day they are at rock bottom. Dude, get checked out, she was with Dennis Rodman. Kind of funny how after that everything went downhill. I'd still do her, but I'd wear protection.

 

[Michael Yount]

The local Autozones here are really good about pulling the codes for you -- no obligation.

I'm guessing you've got O2 sensor issues.

 

[HISSIN50]

No need to guess - But where did FR go?