White powder from exhaust

While doing a trackday a couple of days agao, I noticed the inside of the exhast pipes covered in a white powder. Pic below.

Someone also noticed that the car gave out a funny smell. Like hot paint.

Someone suggested it was the cats on the way out, but I've only just put new Hyperflows in a few months back. Someone else said maybe the car is running very lean.

Anyone have an idea what it is?
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Have you been running any fuel additives?? Maybe do an o2 check upstream of the cats?? Lean is a possibillity, since the cats flow a bit better than stock, but it could also be the cats are doing an extraordinary job .

 

Did you buy fuel at the track? Looks like a racing fuel with benzine...

 

No question about it...... Nigel Stepney has been near your car ;-) (okay, or maybe John DeLorean)

 

I've only been using Shell V-Power (99 Octane). No additives or racing fuel.

Will check the emissions next week and report back.

 

Sy

Does look just like the 355's do when the Cats are failing

 

Same color on all 4 tailpipes, or white only on one side of your 348?

 

LOL.. I was just going to step Stepney after reading the title...

~shahedc
.

 

That's what KHPC said it could be.

All 4 tail pipes are white.

 

...don't worry Angelis, no problem.

This is a sign for a perfect combustion !

Andi

 

+1000!!!

 

Agreed, very possible your cats are crumbling internally. The powder is the ceramic material (dust). An exhaust sniffer should be able to measure your emissions and confirm if the cat has actually failed or not.

 

Does the car have any white actually coming out of the exhaust or is this just the residue that we are seeing?

Look at your plugs. Do they look new (clean)? If so there might be a crack in your head or a busted head gasket. When coolant mixes with fuel it turns into a creamy (milky) substance. This also actually cleans your plugs. If you can post pictures of the plugs it would help.

.m

 

Hmmmm. I thought Hyperflows had no ceramic.

 

+1

 

I would get a proper 4-gas analyzer on the car and see what it is blowing.

The Hyperflows are not ceramic, so I doubt they're crumbling. If the car is severely out of tune, it's possible to cook them, but I think you would have seen a Slow Down light, or CEL during the track day too. Are the thermocouples still plugged into the cats? When you popped the engine lid open during the track day, the cats weren't glowing or anything, were they? How was the timing checked during the engine-out service?

I tracked the snot out of my 348 on Tuesday of last week, and didn't see those conditions at all. HOWEVER, fellow Fchatter 'resnow' tracked his 348 alongside mine (he has straight pipe and single can muffler) produced an extremely similar white powder on his exhaust tips.

 

Will do.

No slow down lights. Thermo's are still plugged in. The right habd ECU has been disconnected as it was causing a slow down before teh cats were put in (when it was decatted).

Cats looked fine. Not glowing at all.

 

I am suspecting this may be normal on a catted car.........

 

Hi,

Maybe the damping material inside the exhaust muffler becomes too hot and caused this ? How are the spark plugs looking ?

Regards, Georg

 

Is fuel/air correct? Looks very lean.

 

Hmm!, Did you import your car from Columbia? Maybe it's had some options, so to speak, added that are not factory installed.

 

Anytime my pipes looked like that, the racers said it was runin fine...if you get this other than at a track event, you are driving way too fast through your hood. These are pre Watkins Glen. White the next few days.
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I was always told that is a sign of running too lean..

 

mine use to do that but it was the condensation/moisture. It turned white after heating up and drying off.

 

You are right and if you run too lean and all the time then you are asking for trouble.