Checked the boot tonight.. large tear alongside the clamp, likely about 1/2 of the boot is ripped... the pipe pushes in past the rip, but likely under full boost pressure it leaks. Called Audi, they have one in stock for $20 CND. Looks like it should take 15-20 mins to replace. Will pick up the part and replace it tomorrow. Will let u know how it goes.

Thanks

-Scott

 

All of TBB's failures I heard of where caused by the clamps. Make sure that the new TBB is a 356T. It replaced the old one( 356N I think)
While you are at it, try to find better clamps.

 

Installed the boot last night... 20 mins work, would have been nice if Audi would have included the clamp for the boost sensor seeing as how the factory one isn't reusable.

Car now performs like it should. No sudden power drop offs, transmission shift smooth. Was a bit suprised about the car's acceleration around 130 km/h, seems to taper off alot more than I expected, my Talon used to do that but at 160 km/h. but will take it out and play with it more when I get a nice stretch of highway.

Might have to do something about the suspension... way to 'spongy' in the corners given the performance the car is capable of. Its just got the stock suspension, not the sport. (Notice it most on on-ramps with the body roll)

Anyway, Thanks for all your help. I am sure I will have more questions as I keep the car.

 

Excellent prognosis everyone !!!
I'll keep that in mind if I ever run into this performance issue.

 

Awesome thread!

I was experiencing the same problems. I got under the hood to check the TBB and I found that the right intercooler hose was not all the way in and was covered with dirt. The left one was clean and all the way in. I cleaned of off the hose, pushed it all the way in. It runs perfect now!!

Thanx!
Bird

 

Hello,

I am new to the Forum....

I too had the same problem with the TBB, big tear around the clamp, I replaced it with a new one and this seemed to fix it for a couple of weeks, but now the boost seems to be very intermitent, I have checked for error code via VAG-COM but there do not seem to be any on the engine.

Some times the car goes like it used to, most of the time it does not seem to spool properly i.e 70% boost.

I have had the DV replaced with forge ones, I have check the vacuum hoses around them, the only problem I could find is when blowing down the dv vacuum hose both disconnected and one sealed I could hear air escaping from the metal pipe work but i cannot pin point it.

I cannot find the f-hose that people go on about although it is a 2001x pre face lift model and i have read somewhere that post 2000 models do not have one, well i cannot find it in the right place the s4's is.

Quick question with the DV should the vacuum hose be coming out on the side or facing up ??

Any help would be good before I check it into the garage.....

 

Same issues here, replaced tbb and all was well for 2 weeks, now I am getting intermittent spool, i.e 70% most of the time 100% some of the time, dv replaced Forge, maf replaced, before tbb boot split error codes, check vacuum hoses cannot find much,

DV vacuum hoses if disconnected and seal one end I can hear air escaping from what looks like the metal pipe work cannot pinpoint it though.

Any help would be appreciated.

Quick question should the vacuum hoses from the DV's be upright or side ways entry, he garage had them upright stretching the pipe, I looked at the platic originals and they where sideways, the firge dv's look the same as the original ones with the piston position,

 

I second that.

 

im having similar intermittent boost issues! but it gets worse.ive changed the damaged tbb, replaced the clamps with updated units. boost issue seems fine. the new dilemna is, every once in a while, the epc light on the dash wont come on when i turn the key on, and the car will just crank over. i let it sit and eventually, usually at least half an hour , the light comes on and it starts and runs fine.happens very randomly but appears to be getting worse, and ideas?

 

Sounds like you may have to do a throttle body adaptation.

details here http://www.ross-tech.com/vag-com/cars/throttlebody.html

The only other thing is you might have damageg the buttery fly valve or have debris in it from when the TBB was replaced.

check the connection to the Throttle valve control part J338 and throttle valve drive G186.

have you checked for any dtc's or cel i.e error codes in the ECU Via Vag-com or other software.