it started a month ago while driving my 06 I was going up a steep hill and it lost all power the check engine light was blinking rapidly. I got over to the sholder and threw it in to N restarted the the thing and went stragt to auto zone as soon as i got in the parking lot the check engine light went out, there were no codes.

now I tried to start my truck to go to work and the battery was compleatly drained

the alternator was tested and its putting out 14.48 DC volts-0.00AC volts
the battery is holding 12.84 volts the battery is 1 year old
their is a power drail of .40volts while off
13.75 @ battery while running
14.48 @ alt while running

what could be causing my power issue

 

the flashing CEL means you re having misfires that would ruin the CAT. I am not sure if your issues are related. it is stange that when you went and had the codes read that there was not a "pending" code......

 

update on the issue everything started ok today but halfway through my shift (between deliverys) I gased up my truck went to restart it to go back to the shop the battery was drained again all i got was clicking checked the volts still 12 volts somebody with a different multimeter checked the amps and found i had only 6 amps on the battery so i need a new battery. still no codes the jack @$$ at autozone still won't check for codes because my CEL is not on. I need to get my own code reader

 

12 volts on the battery, says it's at less than 50% soc.

Leave the gas cap loose on the drive to the autoparts store & that'll turn the CEL on, so they'll scan it. Any port in a storm.....Right!!!! lol

Not sure what you mean by the battery only having 6 amps????

Maybe try another parts store & ask for their test guru to do an electrical system load test, using their portable electrical system tester.
It can properly load test the system with everything in the vehicle & expertly used would be able to spot problems like shorted or leaking battery cells or leaky or shorted alternator diodes, or excessive parasitic drain from things that aren't timing out & turning off.

As powersmoked said, a flashing trouble light indicates misfires & there should have been codes stored.

Misfires sure won't do the cat converter any good, as it'll over heat from having to process all the unburned fuel.

With it misfiring under load on a hill, I might suspect a weak spark problem, maybe excessive spark plug gap, or if the battery or it's cable connections are loose or corroded, a weak B+ feed to the engine sure won't help it run well.

Anyway maybe try another store for the load test & computer scan & post All of the code Numbers found.

 

lol ok ill try that method but i got one prob with it tho when i leave my gas cap off the gas cap light comes on not the cel. I will check the b+ on the coil pack to see if there is an issue

just had the battery replaced after the autozone put there battery tester on it and it failed.

question on the spark plugs do i really need to replace them with platnum or can i use copper core because i just went to 4 auto parts places and none have platnums all they have are the coppers($1.99x6) and Iridium($12.99x6).

 

My experience with trying other brands and copper/Iridium has been not acceptable. I now only use Autolite or Motorcraft Double platinums in my 5.0 and my 4.0

 

Does your Ranger have a coil pack? (not COPs)
If so & your truck has a wasted spark ignition system, then you probably should use the correct Motorcraft plugs or their equivalent (Autolite double platinums?).
DON'T USE ORDINARY SPARK PLUGS OR SINGLE PLATINUM PLUGS WITH "WASTE SPARK" DIS IGNITION SYSTEMS

 

martin_csr thanks for the article that answered my question so i will be spending 50-100 for sparkplugs since its that time I'm about to hit the 100k mark

 

Well you could leave somethig else loose, like the IAC, or EVR electrical connector & they should turn the CEL on, if leaving the gas cap loose won't do it.

On the spark plug question, yah you could use non platinum plugs, but in our "waste spark" ignition system, that works the plugs & wires Twice as hard as the old single coil/distributor system, but the electrodes are going to erode fast & the spark gap will open up such that in 30K miles or less they'll be ready for replacement.
Look in our "Tech Info" thread atop this forums thread listing page, for more info on "Why Double Platinum Plugs.

Right now Autolite has a $2.00 rebate per plug, on their best fine wire iridium enhanced center electrode & platinum pad side wire, plugs.

I recently caught them on sale at Advance at 1/2 off & with the rebate, they came out to something like $2.50 ea.
So maybe print out the rebate at the Autolite site & look around on line at one of the forums sponsers for a much better deal than the $12.50 ea price, or shop more locally!!!!