Little thumping while idling

2003 Taurus wagon,24 valve DOHC,Duratec
Has anyone encountered a periodic rumble/burp/thumping while idling in gear.RPM gauge fluctuates slightly.
Could it be clogged fuel injector or maybe a sign of something more serious on the horizon.
Thanks for any and all help with this.

Welcome to the forum!

Sounds like a misfire. When was the last tune up performed? What year is your Taurus, and which engine does it have?

-Rod

It's been a while since the last tune up.I replaced the wires and 3 of the spark plugs when the car had 30,000 miles on it,it now has 74,000.
Do you have to remove the OH cam to replace the 3 rear spark plugs?
If so probally time for a professional tune up.
Thanks for the fast response.

You certainly won't have to remove the cam to change out the last 3, but it would likely be an easier job if you removed the upper intake manifold. I haven't worked on a 2003 Taurus, but even on my V6 and V8 SHOs where I did remove the upper intake, after the first time it took less than an hour hood up to hood down to change out the bank 1 (rear) spark plugs and wires(V6)/Coil on Plugs(V8).

-Rod

Thanks Rod,
Not sure what I was thinkin',that's just it I wasn't thinkin'.
Intake manifold that's it.
Would you recommend a slightly knowledgeable amateur tackleing the job?

Again, I don't have experience on the 2003, so I'm not sure how much more difficult they could make it than the mid to late 90's engines. If you have a pretty wide selection of sockets, extensions, and wobbles, patience, and are mechanically inclined, I don't think you'd have too much difficulty performing the job.

-Rod