Jwalker000

I bought an '02 A4 1.8t auto Triptronic with 142k on it form the original owner that was well maintained with updates and timing belt replaced and all that goes with it at 90k. It's like new inside, everything works fine except the fuel gauge always showing passed full. However there are 2 things that concern me. There's an exhaust smell in the cab when running the A/C so I have to hit the recirculate button to kill the smell, it's not overwhelming but it's there. Also, right when I get out of the car after parking the exhaust smell is strongest at the middle of the car. I have looked under the hood for a manifold leak can't see or smell anything with the car revving. Can it be the CAT converter?

The other thing is there is a noticeable delay on acceleration from a stop. What it does is from a stop if I get on the gas normal, NOT romping it there's a delay, like about a 1 second delay before the car gets going, after that it pulls strong every gear. I tried using Trip and it's the same thing. Now I figured this was the turbo lag that comes with the territory. Well, yesterday I had to hit the gas hard to get out of a parking lot and it was like it was in neutral or I was slipping the clutch. It made the situation a close call, LOL. It felt like 1st gear was slipping as it took longer to get the car going than if I were just lightly hitting the gas. All other gears shift fine, No noises or clanking when this happens but sometimes, only sometimes it will take off from a stop fine with minimal delay.

This is my 1st turbo ride and i'm aware of the maintenance involved with it and i'm ok with that. I've ridden/owned turbo and SC 1.5L and 1.8L jetski's rated 260+ HP and yes there's a big difference in acceleration from the Turbo vs SC. I'm mechanically inclined to a degree that helps me save tons of money from stealerships.


So my question is, This delay, could it be from a clogged CAT or boost leak and that is also the smell I get when under a load? Or could I be slowly losing 1st gear? The turbo was never replaced or serviced he said so could that be the issue? Do you even service a turbo or just replace it? I've rebuilt many centrifugal SC's but never messed with turbos.

It's been averaging 26-27mpg and getting about 380-400 miles a tank on 91 pump gas if that means anything.

Sorry for my 1st post being so long but I figured i'd try to spell it out in detail.
Thanks!
Jim

GabrielCilia

I had the same problem! Finally my turbo just went capooosh! Last week

Jwalker000

Wow.. I guess I better check it out.

Thanks!

danrgleason

Any update on your trouble? I too have a serious lag in performance from stop. Needs to get to 3,000 rpm or better before strong pulling. I also had slight rattle sound and my mechanic said its the weld on inside of turbo on the wastegate flap. It kind of rattles or flutters when off gas.

Been looking at turbos on ebay but not sure of hit or miss with those or not.
Wish I knew for certain if lag in performance was turbo or not, that is why I wanted to see what happened with you.

Drove a 2005 S4 convertible (6 sp trip) on Saturday and it was embarrassing how that thing pulled compared to my car. I realize the 4.2 V8 has a lot of grunt and no spoolup time, but geesh, it made me think twice about even bothering with the whole Stage 1+ K04 upgrade path because this think was such a rocket compared to my car. Anyway, anything from you on the condition of your vehicle is welcome. Also, I only get 19 mpg so your milage is not bad considering the lag...

kalvina

Sorry but is your car CVT? If so, they all drive like that in 1st gear. Its almost drives like you are slipping the clutch in 1st gear.

westicals

Mine was doing sometime a little similar, although its manual... turned out the honeycomb in my catalytic convertor broke into pieces and was clogging the exhaust.. In addition to that it burnt my downstream 02 sensor up.. If you notice a rattle, it might be worth checking into that... Also check your downpipe from the catalytic converter, it has a flex pipe near the bend, seen a few of them rust out/break...

J4kner

When you say rattling do you mean like a bag of wrenches are in the back on the passenger side? I have that but it happens when I go over bumps so I figured bad suspension or loose tools haha.

But yeah I have that transmission problem too it is just at certain speeds 60km/h when slowing down.. its really harsh. and accelerating up to 40km/h.

danrgleason

No, mine is 5 sp manual. The rattle is like a metal flap sound when I let off gas.

Mechanic said system would ask for like 1500 mbar of boost and my turbo would only give like 1400. He said it is common for the waste gate to give on the inside of the turbo, said it was a broken or loose weld. Said it cannot be fixed. Better to replace whole turbo.

But the other day, I was reading thread where guys bought springs from home depot to help apply more pressure on the actuator valve flap. They were using it to help maintain boost at high levels, but I thought it might help keep my flap closed and not flutter. It was not a lot of spring pressure, something like 5 lbs. And the spring was like 4 inches to not restrict the flap from opening all the way, just to help keep it closed under boost conditions.

I don't have a boost gauge yet so it is hard to know for sure if mine is loosing boost between shifts, but it sure feels like it is dumping out the waste gate. I have to get back up to 3500 or 4000 after shifts to keep the acceleration going.

It will be awhile before I can get a ross tech vag-com also to monitor it in real-time. Right now I can only afford the cheap KKL USB with Vag-com lite. Wish I could see the actual boost pressure while using it.
I wanted to wait until I could afford the vent, motor driven boost gauge (ECS ~$160), and have been avoiding buying the cheap mechanical gauge for $50 but maybe I should get it just to be able to see what it going on with boost.
I would hate to buy a turbo I don't need only to find it be catalytic or flex pipe or something else mentioned on here. With little money to invest, it's hard to pick and choose what to buy...

westicals

Yes that's the sound, mine would rattle on the passenger side for a brief moment after letting off the gas... Didn't happen all the time... Might inspect your downstream 02 sensor just to see if it appears normal... Mine was burnt from the hot honeycomb rattling against it. I heard the noise for well over a year before it triggered a CEL for my 02 sensor.. I just couldn't track it down...

Jwalker000

I finally got around to investigating the problem. This car is an extra vehicle so it rarely gets driven. I found the problem on the exhaust leak, from what I've read it's typical too. The PCV mess under the intake manifold is no good. A big chunk is missing on the piece going into the block and the T section was split almost all the way around and both were pouring fumes. Also the little valve that comes off the manifold corner with an elbow, the small barb was broken off. Would this cause major boost leak & give me my sluggish performance? As for the fix, I saw the 034Motorsport silicone replacement setup. Looks nice! But all I need are the 3 sections, Is that section they make eliminating the metal tube or is there another kit I need for my setup?
Here's some links to my pics.

https://drive.google.com/file/d/0B2i...it?usp=sharing

Whait is that valve that goes in here called?
https://drive.google.com/file/d/0B2i...it?usp=sharing