surging idol?????

[triton1]

I have a 2000 4x4 with the 5.4 in it normally it is a great working truck
but lately the idol has been rough, it goes up and down and when it isnt surging at a stop it seems to idol to slow down around 600 rpm
could this be a sensor even though there is no check engine light on?
has anyone had this trouble before and know what it could be?
I have tried injector cleaner and new plugs but nothing changed.

[rachelh19]

I have the same problem. I have a 2001 ford f-150 with the 5.4 liter. it seems to do it more after its warmed up. I will be driving and when I go to slow down it bucks back and forth. I notice more around 30 mph. I've checked the spark plugs and the coil packs and they check-out ok. I've changed the air filter and plan on changing the fuel filter. I dont know what else it could be either cause there is no engine light on.

[skibo1]

sounds like u have a vacuum leak. the pcv line is usually the culprit at the back of the intake by the iac valve. they get oil soaked and collapse, very common in the f-series. no eng light yet, but prob will come on soon. also the iac is a problem on the 5.4L about sticking, but usually that will be a no idle concern

[2.2 Straight six]

could also be a dirty MAF.

dirty MAF causes all kind of weird things. it can cause the engine to idle rough and not pass 2,000rpm or it can have the revs bouncing up and down.

clean the MAF up and see if that helps.