hollow ringing sound under load

[Dudeland]

I don't know what piston slap sounds like in a 2002, but by playing your video at half speed it seems like it is breaking up a bit at the top end. 

 

If you have a Stahl, chances are you may have a 02 bung installed.   Perhaps a 02 sensor would tell you if you are running lean under load. 

 

A longer video of it being under load and not may help with the ear+armchair diagnosis. 

 

All the suggestions above are good. 

 

 

[Rob Zaeos]

 

8 hours ago, Dudeland said:

I don't know what piston slap sounds like in a 2002, but by playing your video at half speed it seems like it is breaking up a bit at the top end. 

 

If you have a Stahl, chances are you may have a 02 bung installed.   Perhaps a 02 sensor would tell you if you are running lean under load. 

 

A longer video of it being under load and not may help with the ear+armchair diagnosis. 

 

All the suggestions above are good. 

 

 

Thanks! I’ll try to take a longer vid. I have an o2 sensor and it is around 11 at idle, slight throttle sometimes goes lean up to 14.5… medium - full throttle is all around 12-13.. 

I’m starting to suspect an exhaust leak somewhere near the o2 sensor. Looking at it it seems there is a short section of pipe between the header and exhaust that holds the sensor… instead of being welded directly into the header. 
Another clue that may be related is a slight pop/backfire when I let off the throttle at times… 

[Rob Zaeos]

Longer vid for my armchair friends.. 

if you put your phone to your head you can hear the ringing.

 

[jp5Touring]

My old ears can't hear anything.  I had installed a used header that got tweaked in shipping.

Two of the header runners would touch under load causing a ringing did drive me crazy.

I found it by sliding a small piece of thin cardboard between the header till it wouldnt fit.

Then tweaked it with a pry bar to get a little more gap ringing gone. 

Long shot I know If you even have a header ? 

[Dudeland]

11 hours ago, jp5Touring said:

My old ears can't hear anything.  I had installed a used header that got tweaked in shipping.

Two of the header runners would touch under load causing a ringing did drive me crazy.

I found it by sliding a small piece of thin cardboard between the header till it wouldnt fit.

Then tweaked it with a pry bar to get a little more gap ringing gone. 

Long shot I know If you even have a header ? 

I can see that making a clanging sound for sure. 

[Dudeland]

I hear it now.  It kinda sounds like the time the bracket that attached my oil pump to the main bearing cap area came loose. 
 

Perhaps check the alternator bracket bushings. To my ears it is coming from something that is rotating rather than rattling. 
 

I am on my phone.  I will listen to it on my good headphones and re-assess. 

[Clevis Woodruff]

If the sound is what I think I'm hearing in your video clips, it reminds me of a rope slapping against a flag pole or a chain clanging against a tether ball pole.  I'm thinking it sounds like something tapping against something metal that rings such as your exhaust pipe or a front brake rotor, or perhaps a rear brake drum if you still have drum brakes.

 

A couple of questions / suggestions to help isolate what might be causing it:

 

Can you hear it if you are coasting downhill at idle and hitting bumps?

 

Can you hear it during both acceleration and deceleration, and while braking?

 

Perhaps tap on various metal parts around the car with a screwdriver handle and try to duplicate the sound?

 

Just some thoughts.  Squeaks, rattles, buzzing and that stuff drives me crazy.

[Son of Marty]

Look for clearance where the exhaust pipe goes over the rear sub frame, remember it will shift under load and may be just hitting.