New 2008 FX4 with constant thumping sound...

[08Ranger]

I have a new (only 2000 miles) FX4 Ranger with the 4.0L and it has a constant thumping sound even when sitting still. It makes a little thump sound every couple minutes or so even when sitting still. When sitting still, you can see the idle blip a little when the sound occurrs. The sound is kind of muffled, but even passengers notice it. Any ideas what it could be? Is this normal for Rangers?

 

[85_Ranger4x4]

That isn't normal, I would take it back and have the dealer look at it.

 

[camma83]

can u feel it or just hear it? Where does it sound like its coming from? How loud of thump or is it more of a click sound? IT could be the AC pump turning on... If its an 08, u have full warranty on everything still so just take it to the dealer and have them look at it.

 

[MAKG]

I'm attracted to the A/C solution as well. You can try to pull the harness off the compressor to see if it goes away. But there really aren't too many things that thump at idle every few minutes (and that's also a long cycle time for A/C, but that depends on quite a lot of things).

Either that or you have to let the hostage out of your trunk.

 

[4x4RangerGuy]

FYI, the A/C compressors can be pretty loud on Rangers. Since the day I bought my 98 the A/C has always thumped when the clutch engaged.

 

[Jspafford]

Do you have the defrost on? The A/C will kick on and off with Defrost on.

The 3.0L seems to click the loudest comparing it to the 2.9 and 4.0. I think it is because the 3.0 is straining to get it running...

8~)

 

[Southern3.0]

Do you have the defrost on? The A/C will kick on and off with Defrost on.

The 3.0L seems to click the loudest comparing it to the 2.9 and 4.0. I think it is because the 3.0 is straining to get it running...

8~)

Or you just can't hear it over the noisy valve train.

 

[93-4.0L]

I would have to agree with it being the heater or a/c. i know on my truck that i can here the heater kick on and watch the tach jump.

Also i guess it could be something drawing a lot of power causing the tack to jump to. In my truck whenever the subs hit i can watch the needle move but then again you wouldnt be able to here a thumping noise(other than the subs)

I would definately go with heater, a/c idea first though

 

[Bent Bolt]

Mine will thump once when started and once in awhile at idle. 'tis the A/C but mine does NOT do it constantly.

 

[LearjetMinako]

I'm going with everyone else. Most likely its the A/C compressor. Mine makes a loud click noise. Like someone breaking wooden sticks under the hood. And it does drop a little in RPM's but the PCM does quickly compensates for it, just a little rougher idle.

 

[Jspafford]

Or you just can't hear it over the noisy valve train.

I have no...tick tick tick...idea what your...tick tick tick tick...talking about.

 

[91redneckranger]

Do you have the defrost on? The A/C will kick on and off with Defrost on.

The 3.0L seems to click the loudest comparing it to the 2.9 and 4.0. I think it is because the 3.0 is straining to get it running...

8~)

The 3.0 seems to strain itself when it tries to do anything....lol