I have a miss that I only feel when the engine is at idle......

[ukdal1]

I have 98 Mountaineer and when I am at idle it misses occasionally. It does't always miss and it's not bad but it's aggravating. No lights on or anything..... What could cause that? My aunt gave the Mountaineer to me 1-1/2 years ago and she bought it new and kept it maintained pretty good but I dont think she had the plugs or wires changed......could that be it? Also it has 100,000 miles on it. Thanks for any help guys......

 

[Turdle]

Welcome-
98 Mounty's are cool huh?

Yeah-I would change the fuel filter-plugs and wires.
Clean the MAF sensor and get a new air filter-

You might try the "seafoam " treatment before you change you plugs-

Good luck

 

[ukdal1]

whats the "seafoam" treatment?

 

[toypaseo]

Replacing the DPFE helped my idle.

 

[Turdle]

whats the "seafoam" treatment?

The search feature on this site is very powerful-
I would use the search word "seafoam treatment"

when I did this-I found this thread in the list of results--

http://www.explorerforum.com/forums/showthread.php?t=149983&highlight=seafoam+treatment

 

[ukdal1]

I'v tried the seafoam stuff with no luck.......its been getting progressively worse! could it be the pcv, egr, or plugs and wires? or something else? I'm sure whatever it is will be the most expensive route and take the most time to do HELP!!!!

 

[Turdle]

For a miss I would start with plugs and wires myself-

Does your check engine light illuminate? Do you see it when you first switch the key on?

Which engine are we discussing here? You might add i to your info--

 

[ThePhoenix]

no mention of cleaning the Idle Air control sensor? I would check that too

 

[ukdal1]

There are no lights on.....I have a 5.0 also......how do you clean the Idle air control sensor? Thanks guys....

 

[Turdle]

here you go-
notice inside the 2 noles is a sliding shatf and plunger-
try to get all the residue off the little shaft making the plunger move freely-

http://www.explorerforum.com/forums/showthread.php?t=84220&highlight=IAC+valve

Another little redneck troubleshooting attempt would be to swap the coilpacks with each other-
take a picture of them now-hooked up-and lable where each wire is connected (they are numbered) and use if for reconnection reference.There was a recent thread where a bad missing was repaired by this-

I would definitely replace the spark plugs.
You'll be pleased to know it is a 30 minute job on these trucks. Jack up the front, support with a stand-(I remove the front tire and place it under the running board-frame area for safety)) and go in through the wheel wells. very easy!!
Use a 5/8" spark plug socket.
Don't go for high dollar gimmick plugs-
autolite platinum are fine. They sell them at walmart.

 

[ukdal1]

I cleaned the IAC.....no luck. I guess I'll try plugs and wires next