New to the board - have my first question.

Last night while stopped in traffic, my 97 F150 (4.6) started idling a little rough. About 20 seconds later the Check Engine light started flashing. The truck was running a bit rough, almost like it wasn't running on all cylinders. The Check Engine light has remained on, sometimes flashing and sometimes solid. Any thoughts on something that I should check before I take it to a mechanic or should I just take it in and get it checked. Thanks for any input.

 

A flashing check engine light means the engine is mis-firing, I'd check to see if your plugs and wires have ever been replaced. How many miles are on it? Some people around here say to change out the plugs and wires as early as 60,000. In general though only a code reader can tell you what exactly is going on. Your Check Engine light will stay lit solid for 3 warmup and cool down cycles and if the problem that caused the mis-fire dose not happen again the light will then go out. If it dose not then you will have to take it in and have them read the codes to find out whats going on. Or you can always disconect the battery for 10 min and that would shut the light off however you would still have a problem nd it would most likely come back on.

 

Let me know if you come up with anything. My "Check Engine" light comes on when I'm slowing down coming to a red light. It goes off when I stop or accelorate. The vehicle still idles and runs fine and all the gauges look good. My truck is a 1987 with only 67000 miles.....

 

Bought truck about 2 years ago. Had approx. 120000 km on it then, approx. 140000 km on it now. I guess I'll get it looked at when I get back after the long weekend (Monday holiday here in Canada). Will post results when I find out.

 

Could be a whole slew of things. Bad plug. Bad wire. Bad coil. Bad IAC (Idle Air Control). etc.

The best thing you can do is get the code read to pinpoint the problem. These days, hit & miss repairing can be expensive.

 

What is a code reader, where can I get one, and how would I use it? I'm surprised my shop manuals don't even cover this.... .....

 

If this is the first time it has happened to you wait a while longer for it to do it again. If it doesn't go away check normal things like running codes to see what is you get. I have a 97' and had this very similar problem, I had bunch of yahoo's look at it and found out $1200 later that is was the computer. I had dealer look and they told me of course that I needed to replace the O2 sensors, and plug wires, plugs and a bunch of other *****. I ran codes myself and traced whole wiring harness for shorts to ground and found nothing wrong, Finally ended up being computer.

 

Well, the Check Engine light went out this morning. For the most part has been running better the last couple of days. Would it still be recommended to have the codes read or should I just wait to see if it happens again?

Thanks for your responses, both to date and new ones.