I’ve had a 2005 2.3 ranger for a little now and it runs great, well besides one thing. Pretty much everyday I drive down the highway it starts to randomly lose power, and I have to downshift for maybe 4 seconds until it gives in and goes again. I got so used to downshifting now every time it loses power. If I don’t downshift, the rpm’s keep getting lower and lower and knocks start to occur sounds like it’s coming from the firewall somewhere…

what I have done was replaced spark plugs, and Oil change, fuel filter, fuel pump replaced. I have no cel but the light does work.

I have read similar issues and could it be the cat converter? Im all out of ideas…

 

Welcome to the forum

The "knock" is not good, unless you mean spark "knocking/pinging" which is still not good but would point to a Lean Issue

I would invest in a Bluetooth OBD2 reader, under $20
You can then watch Live Data, see what the computer is doing, and what the computer is "seeing" from all the sensors when the problem occurs

O2 sensors are the ONLY sensors that wear out on a time line
12 years or 100k miles
After that they are costing you money as MPG slowly drops because computer "thinks/sees" that engine is running slightly Lean, but a false lean, and they won't set a code until they are WAY WORN OUT, and have cost you 5 to 10 times their cost to replace with lower MPG

So same as spark plugs need to be changed, so do O2s
Is that your problem, probably not, but certainly wouldn't hurt, 2005 should be on its 2nd set of O2s, unless its over 200k then on its 3rd set

Yes, could be clogged exhaust, Cat or muffler breaking up inside, can use a vacuum gauge to test for that, but that tends to effect highway speeds above a certain RPM and doesn't go away
Tap on cold cats and muffler with rubber mallet or piece of wood and listen for internal rattles

 

Thank you, yes my mpg is terrible I’m getting about 14mpg right now. I tried tapping the cats but couldn’t hear anything too noticeable. I can’t tell if the knocks are backfiring or not? I will invest in that scanner thank you for that! And I will also look into the o2 sensors

Also something interesting; this seems to happen over a certain hill I go up on the highway and once I go over the hill and start driving downhill it begins the power loss. Don’t know why it’s almost guaranteed on this certain hill…

 

Bluetooth OBD2 reader will work on ANY vehicle sold in US or Canada 1996 and up, its "the Law", so a good tool to have in the box

If cash is tight, when isn't it, lol, just change the front(upstream) O2 sensor for now, but do it sooner than later

Need a 22mm or 7/8" wrench, 22mm is spec, 7/8" works

Bosch O2s were OEM(Ford used them)

You should be in the 23-25MPG range
Loss of power after going up the hill, high fuel demand, could be caused by flooding out engine when demand drops, failing upstream O2 could cause that

 

here are my o2 sensors I just replaced them both with Bosch and so far on the first drive it went smooth! Hopefully this was the issue but I will update!

 

Solved!!

it was indeed the o2 sensors. Drove it for a while now and I no longer lose power, thank you Ron!

 

Good work

Thanks for posting THE FIX