Last week my 4.6L Explorer began idling very rough and finally would die. I pulled into an Express Oil change where they replaced the Idle Air Control Valve. It cost almost $200.

Well today, at idle I began getting a bad hum / rumble from the air intake. Sounds like a blower.

I have read other threads, but they all seem to said the IACV is bad, but I just replaced it.

It also has a new air filter from Express.

A car guy around here mentioned it could be the throttle body could be gunked up and that should always be done when replacing the IACV.

Ideas about what this could be and how much it might cost?? Thanks!!

 

Welcome to FTE clspruiell,

What is the mileage on the Explorer?

There are a few things to consider.

Are you able to do some mechanical work yourself? such as inspection,

Cleaning? OR do you take your vehicles in to a shop for this type of work.

Do you know if the IAC was actually replaced or just "CLEANED"?

The "new" IAC could also be a defective part too.

One thing you can do is check for loose hoses or fittings first.

Visually check for proper air filter fit too.

It is apparent that this noise/condition started AFTER the "repairs", Correct?

 

Thanks for your prompt reply.

Yes, the bad humming came AFTER a new IAC valve was put on just 3 days ago.

I really don't want to do much mechanical work myself. I have a very trusty indy guy that I like and he mentioned the throttle body and/or a vacuum hose.

 

Look for loose fittings in the upper intake area.

The auto tech may have accidentally loosened a hose or fitting.

OR

take it to the shop that did the repair and DEMAND they fix it.

Good service gets referrals.

Bad service gets lost business.

 

Update... I had Express replace with the same part, within 5 seconds, humming again. So we got advanced to bring us another brand (idk which brand) and its been working well for a day and a half.

The ONLY thing I see is sometimes it'll bog down to around 500 rpms while sitting still. It's usually quick to correct itself, but acts like it wants to do the same thing. That does not happen every time I stop at a redlight, just sometimes.

 

Some after market parts are not up to the task...
You may consider cleaning the intake manifold and butterfly.. Philip