I have a b5 with stock everything, and the other week I had to follow a friend through some winding country roads. His car is a lot faster and I had to keep up, really riding the engine hard, but never redlining or coming too close. By the time we were done, about 20 minutes later, I noticed a burning smell, and when I opened the hood it looked as if there was a lit lightbulb inside my engine (this was at night, pitch black). When I looked deeper I saw that the section that the turbo attaches to was glowing bright orange from overheating. I let it cool for a few hours before driving again.

Since then my car has been driving as if it has no turbo at all. If I go above 3000 rpm my engine sounds like a vacuum cleaner and theres hardly any boost at all. I now have to drive between 2000 and 3000 rpm - and it drives pretty normally - but if I go any higher I'll notice that the turbo gets hot again (by looking under the hood and feeling the heat eminating from it).

Basically what I want is for you guys to give me all the possibilites of why this is happening so that I don't buy a new $500 stock turbo, spend 4 hours installing it only to find out nothing has changed. Can this be anything besides a blown turbo? All my belts, ignition wires/coils, plugs were replaced a month ago after my engine was misfiring badly, and since then its been running smooth until the fast-driving incident which was like 2 weeks ago.

Also, how urgently does this need to be fixed? If I continue driving carefully, can I put this off for a month? Is there anything that needs replacing in conjunction with the turbo? Can I keep the same catalytic converter, oil lines, etc?

 

you see your turbo getting hot enough to glow red is a sign of using it hard. its not necessarily a bad thing, it just happens. thats why they call it the "hot" side of the turbo. that is why you are suppose to keep the engine running for a few minutes after driving hard to let everything cool down, ie your oil will sit in there and cook if it isnt being recirculated, and that is a bad thing. i would say you can drive it like that unless you get a cel. what you do need is to get a boost gauge and post the readings.

 

yea thats your turbo that is glowing, you really shouldnt turn the car off if its red hot like that, but its hard to say if the turbo is bad, they usaully make a nasty noise when they die, maybe a cooling issue

if it is the turbo, i believe you can buy a used one for like $100-$150

mods? chip? boost gauge? vagcom?

 

Could be the cat too.

 

actually that would make a lot of sense. if he got it really hot and melted the cat, his turbo wouldnt work great once in boost because there is too much back pressure. a very deffinant possibility.

 

If I take out both the turbo and the cat converter, how can I tell if they need replacing? Is the turbo fine as long as there are no visible cracks or dents in the blades?

Since my car was going through a period of misfiring and arching, it is possible that unexploded fuel may have seeped into the converter for the two weeks that I was driving it like that. This may have contributed to possible damage when the thing got all hot.

Do I have to take it to a mechanic or can I figure this one by sight? I can post high quality pictures if it's worth a look.

 

yeah i am leaning towards your cat being shot. when unburned fuel goes through your system, it sits in the cat until it gets hot enough to burn and melt the cat down which in turn resticts the flow of air so your turbo will have too much back pressure. i wouldnt be able to tell for sure with the limited amount of info, but i would guess its your cat. of course this sort of happening would throw codes. we need them....
as long as you can turn a wrench, you dont need a mechanic. i hate it when someone bitches about how much it cost them to fix their car when it would have cost half as much had they done it themselves. you will not be able to figure it out by sight, im assuming. you could always take of the turbo and cat to inspect them. i think its nine bolts in all...

 

Another good indicator besides getting the error codes is your check engine light. Does it flash? If it does, then there's no question it's your cat. It also says so on page 116 of your owners manual.

 

When the mechanic gave me new wires last month he also reset the computer which was giving codes because of all the previous misfiring, and when I got my car inspected a week later it passed, and the light has not come on since.

I think when i have $150 I'll buy a replacement catalytic and install it. If I remove the airbox and have the front up on jack stands, remove the belly pan, will I be able to reach all the necessary bolts, and can the turbo remain in place while I remove just the cat? Are there any oil lines/fluid lines connected to the cat that might seep fluid and require topping up? In the photo I posted up is the part I circled in red the cat?

 

as far as i know its six total bolts. where simple simple procedure. just spray the bolts with pb blaster the night before or you wont get them off. plus you will have to remove o2 sensors. i would recomend changing them if they havent been yet. turbo can stay in place whole time. all you need to worr about is six bolts and two sensors. straight forward. you might not even have to take anything else off.