Ford F-150 Check Engine Light Codes- Dead Battery

Question: I have a 1999 Ford F150 V6 it give a check engine code saying a misfire on cylinder 6 but it doesn’t do it all the time. When the computer code is cleared it runs great for weeks but then starts to run rough and says it is running lean again.

Answer:
I’d try and find what’s causing the misfire such as a bad spark plug or ignition wire, possibly a coil or ignition module or even a wiring problem. When it is acting up is the best way to try and find the problem.

So it wouldn’t be the computer module?

Not likely.

Ok thanks i will look into it next times it does it . I just don’t know why it doesn’t do it all the time?

Probably an intermittent condition due to a loose connection from wire to plug, or moisture, etc. Sometimes those are the hardest problems to fix. Try wiggling wiring harnesses when the engine is running to see if you can make the problem occur. Then you would know what to concentrate on.

You said it. Thanks for your Help. I will try to fix this know myself.

You’re welcome, good luck!


Battery Dies When Truck Off

Question: When my F-150 is turned off for a while the battery dies. I have changed the cables, got a new battery, and the alternator is testing good. 14.5 volts. Don’t know what is wrong and where to go from here.

Answer: Your truck probably have a parasitic draw on the battery that is discharging it after it sits. Do you have any aftermarket equipment on the truck like an alarm, or remote start, or other accessories?

No.

Ok, well I would recommend checking for a draw on the battery. Do you know how to do that?

No.

Do you have a volt meter that reads amps? You won’t be able to check for a draw yourself then. You’ll have to get it looked at. You can use a test light between battery positive cable and post, turn key off, and see if light is on dim. Or you can use a meter described below.

Thanks for the help.


Battery Draw With Key Off

Question: Why does my 1994 Ford F-250 still have power going to the battery when I turn my key off? After a while it will go dead.

Answer: Not sure what you mean that there is still power GOING to the battery. The battery is what produces the power, not receives it. If you mean that there is a power drain of the battery when everything is off, this is what is called a parasitic draw. You would need to isolate the circuit that is staying powered up by removing fuses until the raw goes away, then fix the problem.

You can check for a power drain by putting a multimeter inline with the negative battery cable disconnected and the post and look for a draw of more than .5 of an amp.  Then start removing fuses to find out what system is having the problem.

Common things are a center console or glovebox light staying on.