check engine lite

[D]

I'm going to have to run some codes, but I've been so busy i yet had the chance.but this is what's happening.i can drive the car all around my city with no prob 15mph to 50 mph.but i soon as i get on the high way and go 70 then come off the and go normal speeds the c.e.l basically goes on and off in till I shut the car down and start it back up.
The wired part my sho has never ran as good as it is now..any help with my prob would be great!

 

[wuzzzer]

My 93 used to do the exact same thing. More than likely you'll need your oxygen sensors replaced. There's 2 of them, make sure to replace both.
You'll probably notice a little better gas mileage after you replace them, too.

 

[sdpatt]

Just for information, here is a good site describing the EEC test. The 2- and 3-digit codes are available as links near the top of the page.

http://www.dalidesign.com/hbook/eectest.html

 

[Sho Nutz]

My car did the exact same thing you are describing right after I bought it, and just like Wuzzzer said, it was the o2 sensors. One was Slow to respond, the other was zero response.

I replaced them with the OEM part and the problem has never returned....