check engine light is on

[catman]

Hi there, I am new here and have a 91 240 SX at w/140K it runs graet gets 31mpg on the hwy, my problem is a check engine light comes on and off and sometimes stays on and sometimes I can get it to go off if I run it at 70mph for a while. What can I do to fix this. I took it to a dealer they said the light never came on and they can't help me unless the light is on, you know the car knows that too....Before you say check the engine codes I don't know how to do that or where I can find them, can anybody help me?. Thanks

[LiU]

when the system detects something wrong,it turns the CEL on. However, after 3 drive cycles (I tihnkit's 3, not sure of exact #), if the problem doesn't persist, it turns the CEL off.

a drive cycle = turning car on when it's cold, runing it until it heats to operating temperature.

when the next time it is on, take it to autozone and get the CLE checked, they do it for free.

[catman]

Can you explain what a CLE is or a CEL? I am confused also this light has been doing this for 9 months, when it happanes the car needs more peddle and it feels like it is not getting enough air, from reading the other threads I thought it sounded like some sensor or O2 or something might need replacing.

[M2-BM]

my bros eclipse had that.... check your spark plugs. i think that was the problem

[kamikazestorm420]

go check your ecu to see what code its throwing out.

my cars CEL used to go on and off and i checked it and it was the egr valve and the o2 sensor.

[ricebike]

catman,

here's how to check for codes:

http://www.240sx.org/faq/index.html

http://www.240sx.org/faq/artic...h.htm

post what u get from your car's pc...

[catman]

Thanks guys for all the help, I have been a little slow responding, I will follow the suggestions, hope this solves the problem.