Rough idle.

[Exproblems]

Hi All,

I'm new to this site, so please bear with me. I have a 2005 Ford Explorer with a 4.0l v6 with approx 84, 200 miles on it. I am currently experiencing a rough idle either while the vehicle is in park or in gear, sitting idling at a red light. The rough idle tends to fluctuate at times, seemingly worse after the vehicle warms up or when the outside air temp is warmer, say 60 degrees or more. I am also getting poor fuel economy, 10-12mpg depending on city dfriving or highway driving, it's killing me $$$$ on fuel costs. The CEL has not come on as of yet and I have replaced the spark plugs, wires and fuel filter and have even had a fuel injection cleaning done at a Ford dealership. The rough idle is still there. I took the vehicle to a repair shop (first time to this place), they claim they did a bunch of tests on the engine components, MAF, EGR, vacuum leaks, Intake Manifold gasket leak test etc., but can't locate the problem. I am not 100% sure this repair shop actually did what they claimed on my vehicle as far as these tests, so can anyone in here possibly direct to me the source of this rough idle problem I am experiencing? Any help would be greatly appreciated, thanks!

 

[Sams01XplrSprt]

welcome

 

[swetrid]

Sounds like you have a bad harmonic balancer/ damper. They are common on 2004 and 2005 4.0L. If you reach inside the center of it you will feel a loose ring. They are a couple of threads and pictures out there.

 

[Exproblems]

>>>>>>>>>>>>>>>Sounds like you have a bad harmonic balancer/ damper. They are common on 2004 and 2005 4.0L. If you reach inside the center of it you will feel a loose ring. They are a couple of threads and pictures out there. >>>>>>>>>>>>>>>>>

Thanks for the info "Swetrid". The repair shop I took my truck to mentioned the harmonic balancer could be out of balance but he did not check anything with it. I have a question though, if the harmonic balancer is out of balance, wouldn't it cause a rough idle all of the time, no matter what temp the engine is at or how hot the outside air temp is? It seems to be worse at operating temp and when its warmer outside. Colder days you don't notice it as much except for when the engine is fully warmed up. It also has never stalled the vehicle, I forgot to mention this in my original post. Thanks again for the help and info I'll look for those HB pictures.

 

[Exproblems]

Swetrid,
could an out of balance Harmonic Balancer also cause poor fuel economy like I am currently having, 10-12 MPG? BTW, I found some info and pics on here about the Harmonic Balancer problems in Ford Explorers, thanks again for the help and info.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the stock 2002-2005 section.