1999 A4 1.8T Quattro- Replaced Turbo Fall 2007
Catalitic Converter cracked, professionally welded two weeks ago
Exhaust / Cat has a mild but noticeable rattle, around 3,000 rpm's
Changed Spark Plugs today, noticed back plug was covered with residue
Turbo/ Exhaust Manifold/ Beginning of Cat Hot and Glows Red after normal driving

Any ideas????

 

well it depends on your driving habits, for the glowing turbo make sure all the cooling lines are good and not leaking. ive seen glowing turbos before after normal use. for the plug which part of it had residue, if it was the top it prolly was not tight enough, if it was the bottom, check the plug and the coil pack, but that would have thrown a code if it was misfireing. oh and the exhaust, it could be a heat sheld or the inside of your cat or a bracket, mine rattles to

 

Time to pull the cat off and inspect it to see if it is coming apart.

 

It's more than likely your cat that's making the sound. Your car sounds like it's burning to much fuel. Which would cause the glow, cause they are getting to hot.... I Had an S10 that had fuel issues and you could see the manifolds glow BRIGHT red after driving it. Looked Kind of cool, but then realized that's no good.&nbsp\\; I've heard of a little bit of glow not being to much of an issue. But I figured i'd throw out my Opinion. But if it is your catalytic converter, there's a reason it's no good anymore. I'd check it out for sure. Especially with the Gas prices we're gettin dicked with.....

 

and once i fix the problem.. what do you guys think about putting a testpipe on instead of the cat??

 

test pipe sounds good for off road driving only! jk

 

you don't think i could get away with it on the road

 

I have a test pipe. But I only got a C+.

 

Anthony,

The Cat is BAD, that's why it rattles and that's why it glows. A test pipe is fine on the road as long as your state doesn't do emissions testing. Change your oil immediately with synthetic. This is the 3rd turbo on this car and the red glow (high heat)will destroy the center bearing and seal again! A new O2 sensor is a good choice as well.

 

Another thought trade it in for a Volvo!!