I was out driving and noticed that my idle RPM rose. Usually it hovers below 800, but then just started going to close to a 1000. I also noticed my battery light on (which was replaced a few months ago) at the red light. However when I gave it gas and moved, the light turned off.

Today it was fine going to work, then this afternoon for lunch same thing. Higher than normal idle plus the battery light on that turns off when giving it gas. Not sure what the issue could be.

I don't have the factory alternator as it was replaced when it died out a few years ago, just in case that's relevant. I've also checked all cables that I can see and they are snug. And ideas what it could be? It's an '04 FX4.


Ray

 

Sounds as if its the alternator. Have the battery and alternator load tested.

 

Maybe the alternator is the issue. Not sure how that works, but it would make sense for the truck's computer to increase the idle in order to provide enough power output from the faulty/weak alternator.

 

I will go get it tested. Thanks for your advice, as always.

 

Well the alternator tested bad, so I went ahead and started to replace it. When I went to loosen the tension on the belt, the damn belt tensioner thing snapped. More specifically, the part where the 1/2 inch ratchet goes in to loosen it. Just sucks.

 

Not sure how strong you are... most automatic tensioners I monkey my arm in and grab it and move it enough to take the belt off no tools required.

I've done this on a lot of vehicles. Then again, I weight lift/body build... so that might have something to do with it.

I've done a few 5.4's and if I recall correctly, I just get the new belt on all the pulleys then pull down on the tensioner from underneath the truck on that particular engine. Haven't done one in a while... but I believe I crawled on the ground to get at it.

I know on my 4.7l V8 on my Dodge, I do it from up top and pull the tensioner upward, and on my 4.2l F150 I do it from up top and pull it upward too. My 2.4l World in the Jeep I push to the side, and is really easy because it's a lighter tension, probably because its a smaller engine.

Edit: I just re-read your post... I don't like using that 1/2 inch hole. I use the actual nut on the on the pulley if I can. But in this case you can't because it's turned. So I remembered that I used the tensioner arm like a handle and yanked down on it. I remember doing it from the bottom though. It wasn't hard.

 

It's not that you can't do it that way, the question is: why would you? The tool costs $5-10 at most big box stores, or they rent them for free at most auto parts stores. Why take a chance on busting up your knuckles/forearms trying to move something with brute strength when you can use leverage to your advantage? It's like using a 1/4 drive socket wrench to remove lug nuts on your wheels.

 

Yeah I don't have that arm strength. lol

 

Yanked on it is kind of exaggerating a bit... I found out the first time working on a car a while back that I left my tool sitting on the table, and got curious and pulled up on it, and man, this is a hell of a lot more convenient than using the tool.

Yes, I'm strong... and I know my limits, but if I can do it without tools, and haven't busted my knuckles, why stop while I'm ahead. Besides, if it don't move when I tell it to... then I bust out the heavy artillery.

Personally, I feel more comfortable using my hands doing the process because I've got complete control and not having to worry about the tool slipping off and getting my finger stuck under a belt accidentally.