What went in this hole in my M113 V8 CLK Exhaust ?

[tjamesbo]

Exhaust suddenly starts blowing and i found this hole ,something was here a blanking plug perhaps ? It doesnt look threaded but hard to see inside
was it a facility for a sensor on american / export models and was blanked off for uk ?
engine is running fine no faults on the dash computer no loose wires or a sensor hanging loose
best way to restore it / blank it
mercedes blanking plug ???
not sure if welder can get in there
bolt and washer glued in with gun gum
Any further suggestions welcome
Boyd

 

[RogerSausage]

Yep, it was a blanking plug to go where US spec cars have an extra lambda sensor.

It happened to my car too and I got a cap welded over it.

 

[Jobsworth]

.

 

[noogieman]

dealership don't they sell cap with bolt to plug ratholes like this?

 

[RogerSausage]

dealership don't they sell cap with bolt to plug ratholes like this?

In all honesty I don't know, I've never enquired. The exhaust place I use just made up a little cap out of stainless steel and TIG welded it on nice and neatly. I don't have an "after" photo unfortunately.

 

[noogieman]

In all honesty I don't know, I've never enquired. The exhaust place I use just made up a little cap out of stainless steel and TIG welded it on nice and neatly. I don't have an "after" photo unfortunately.

Our C43's have oxygen sensors in front, rear oxygen sensors threaded holes are plugged.
Only NA market cars had 4 oxygen sensors.

Did one of your plugs come off just like that, from vehicle vibrations plug unscrewed itself and fell off the exhaust?

 

[RogerSausage]

It didn't unscrew, it just kind of "spat" the middle out where the material is a bit thinner. Just corrosion I assume, although the rest of the plug looked solid. It was quite strange.

 

[noogieman]

It didn't unscrew, it just kind of "spat" the middle out where the material is a bit thinner. Just corrosion I assume, although the rest of the plug looked solid. It was quite strange.

I shouldn't expect this "spat" the middle out where the material is a bit thinner. Just corrosion I assume from not driving my car in winter?

How did you notice this plug was missing?
Did you notice any strange exhaust tones from the car?

 

[RogerSausage]

How did you notice this plug was missing?
Did you notice any strange exhaust tones from the car?

I first noticed it in a multistorey car park, I could hear what I thought was a leaking gasket. The telltale "tick tick" noise. Once it was on the ramp the source became apparent!

 

[noogieman]

I first noticed it in a multistorey car park, I could hear what I thought was a leaking gasket. The telltale "tick tick" noise. Once it was on the ramp the source became apparent!

The tick tick noise comes from stainless steel exhaust when it's really hot metal expanding.
I have heard this tick tick noise after sometimes not driving in legal speed and the exhaust was very hot after.
Damp in the exhaust system cooks which is good.

On normal driving I never hear any tick-tack from the exhaust

 

[RogerSausage]

This "tick tick" noise was from the exhaust gases escaping from a tiny hole, the same as when an exhaust manifold gasket leaks, a bit like a rattle.

 

[noogieman]

This "tick tick" noise was from the exhaust gases escaping from a tiny hole, the same as when an exhaust manifold gasket leaks, a bit like a rattle.

so this is different compared to when hot exhaust system ticking after a spirited drive feeling all AMG ponies?
Stainless steel exhaust systems always ticks when they are really hot after shut down standing next to the car.

 

[RogerSausage]

so this is different compared to when hot exhaust system ticking after a spirited drive feeling all AMG ponies?
Stainless steel exhaust systems always ticks when they are really hot after shut down standing next to the car.

Yes mate, this was whilst actually driving the car. I noticed it in a multistorey as it was echoing off the walls and I had the window down.

 

[noogieman]

When the exhaust is unplugged with the cap fallen off, did your car run worse?

 

[RogerSausage]

No, no discernible difference at all, just an annoying noise!

 

[noogieman]

No, no discernible difference at all, just an annoying noise!

Came to think about another thing?
With the plug missing from the exhaust, could fumes seep out entering cabin and slow poisoning people causing headache?

 

[RogerSausage]

Came to think about another thing?
With the plug missing from the exhaust, could fumes seep out entering cabin and slow poisoning people causing headache?

I'm not sure it's any more risky than say, side pipes on an SLR McLaren or a Cobra etc. Where the bung is, it's in-line with the front of the transmission oil pan, so behind where the ventilation system draws fresh air in.

 

[noogieman]

it's pretty safe then.

exhaust fumes are sneaky which could make you sleapy.