when my engine is running idle it sometimes gets a little power loss like its gonna try to stall out, its been doing this a little on and off for a while now, i just recently changed out my plugs, and did an oil change. And its still happening. still need to do my fuel filter. Maybe my alternator?

i have a 97 f150 5.4 4x4

 

It could be a clogged fuel filter, dirty injectors or even the fuel pump could be on the way out. This is where I would start.

 

ok thx, im gonna change out my fuel filter tomorrow and see what happens

 

That's the best bet, always start with the simplest thing first and go from there.

 

You might want to look at your pcv hoses too. I had a idling problem about a month ago. It got progressively worse until the truck starting stalling at the redlights. I had a check engine light on too. The codes were 171 and 174, I think. I replaced some of the pcv elbows that had cracked and were sucked in. Idled perfect after that. Disconnected the battery and the engine light stayed off.

 

where are the PCV hoses located?

 

Clintc,s suggestion is a good one.
On a 5.4 it is very common for the rubber elbows on the PCV line to rot out and cause vacuum leaks. My 97 5.4 had this happen at 107K miles and caused rough idleing then eventually stalling and check engine lights.

The PCV valve is located in the passenger side valve cover, it has a hard plastic line that connects to a rubber elbow behind the throttle body..
Feel around on the line and you will most likely find them turned to goo.

The whole assembly with valve, line and elbows , costs about 20 bucks from Ford.

Another common idleing problem can be caused by a dirty Idle air bypass valve.. These can be cleaned with throttle body cleaner with good results. You have to take it off to clean it,,, and thats a pain on a 5.4 but its worth it.

 

Morning all. I am having the same trouble with my 6 cyl. I have good and bad days, but as the truck gets warmer the trouble gets worse. It will come to almost a complete stall at lights, and when I step on the gas it will choke. Occasionly I will get a wiff of gas when I park and turn it off. The fuel filter has been changed recently, but I did not think of the pvc pipes.

Have a great day!

 

EGR tubing is NOTORIOUS for leaking(97, 98), starts with a dimple, then over time melts into a huge hole, by then you get a CEL... but if it's a minor leak, you get a low/bouncy idle. See 864lightning's post to follow this up (elbow included)