Well i bought my first Audi a month or so ago and i really love it, but from day one the car seems really sluggish, like it is not coming onto boost. I have driven turbo cars before and am pretty mechanically inclined so i think i would know whether its boosting or not, but it just doesnt feel like it? i was just wondering maybe because the turbo is so small that you wont feel the boost as much?
Anyways thats my problem and to get to the wastegate rattle, everytime i let off the throttle there is a loud rattle, like metal clanging, and its coming from the wastegate, i know because i put a screwdriver on it and it is clear as day.
Well just thought maybe somebody might have some suggestions, o and my car is a 98 b5 1.8T, 5spd. Thanks.

 

well i have the wastegate rattle as well.. but my car boosts normal.. its stock ECU mapping with a KnN intake and forge DV.. but my boost gauge reads 5-8 psi under normal and hard acceleration which from what i hear is the stock levels for our cars.. alot of people say the rattling can be attributed to the loose nut on the actuator arm of the wastegate, and it rattles.. i wanna tear my front end down to fix this problem just havnt gotten around to it.. makes my car sound like garbage! haha.. hope this helps a little. also check for boost leaks if you havnt, they are the most common reason for the sluggish feeling and loss of boost.. there are DIY checks you can find thru search im sure.. if any or all of this doesnt help the issue then it might be a dead wastegate but it sounds like that isnt the problem.. good luck man!

 

Yes adjust the arm nut to be tight again.

Yes it is a small turbo but you should be able to feel boost. You might want to check the vac line that goes from the intake mani to the diverter valve. When I bought my car that line had holes in it but becuase of the outer housing I couldn't see them. if that line is chewed up then your diverter isn't closing and therefore not giving you boost. Start by replacing that line.

 

Thanks man, i have checked for boostleaks, i made up a abs cap with a valve stem in it and clamped it in the intake tube. But that wont tell me if my dv is gone because it charges both sides of the DV. Im pretty sure i have a problem, have to get a boost gauge to be sure, put it this was, i have a 95 civic hatchback si and it is alot faster than my A4, to me that shouldn't be???

 

Thanks Bishop, i tried that already, when i first got the car i did ALOT of reading and went over the car before i even really drove it much, just to see if i could find anything in comparison to what i had read.

 

OK so i am getting that same thing with not having a lot of boost and getting a rattle when i let off the throttle. The thing is that my boost gauge is still saying that it is making 12 pounds of boost. In these cars a big problem with them tends to be the waste gate actuators (already replaced one) so i just ordered a upgraded one from Forge Motorsports through horsepower freaks which will hopefully fix this issue. I will let you know...

 

The other problem is that it could be the wastegate flap itself inside the turbo (yes mine made the off-throttle rattle). When I replaced mine is was very loose, and I don't know if there is any way to fix it since it's basically a giant rivot. You can see in the pic by the shadow that mine was loose.

 

Well im wondering if mine is the actuator or the flap because i was reving the car while under the hood and the wastegate does move the actuator, i just cant tell if it is hooked up or the flap is broken. Would it still read boost?

 

It depends on the type of boost gauge you have... mine runs into the fuel regulator hose. So mine says that it is making 12 pounds because it is going by how much fuel the engine is calling for. But i can tell you from experience that it is not actually making any boost at all (the first year i owned the car i did not have a functional waste gate actuator so the turbo was spinning but the waste gate was open so no boost pressure could build up). Also i have a friend of mine who widened the hole around the waste gate and that helped with his problem somewhat...

 

That doesnt really make any sense to me, hooking up to the fpr vac line shouldn't tell you anything about the fuel. Hooking up to any vac line should read the same output, boost or no boost? am i wrong?