loosing boost? how long do stock diverters valves last?
03-20-2007, 09:00 AM
#1
AudiWorld Super User
Thread Starter
loosing boost? how long do stock diverters valves last?
hae3 78k on the car, it seems to be slowing down, has the stock valves still. non chipped. any easy way to tell? also where is the best place to tap the vac line for a boost guage?
03-20-2007, 09:14 AM
#2
AudiWorld Uber User
Join Date: Mar 2000
Posts: 66,965
Likes: 0
Received 0 Likes
on
0 Posts
Take the valve out and test it.
push the piston on the bottom side, put your thumb over the vacuum side nipple. If the piston snaps back to it's resting position once you release it, there is a hole in the diaphragm, and it needs to be replaced.
03-20-2007, 11:58 AM
#4
AudiWorld Uber User
Join Date: Mar 2000
Posts: 66,965
Likes: 0
Received 0 Likes
on
0 Posts
Well, it's helpful in that it helps you determine if there is a leak in the
internal diaphragm. But for aftermarket valves, you can have other situations like a sticking piston, which you may not discover when performing this test. I'd say it's definitive when dealing with an OEM/Bosch valve, but not definitive when dealing with aftermarket valves.
03-21-2007, 10:23 AM
#7
AudiWorld Uber User
Join Date: Mar 2000
Posts: 66,965
Likes: 0
Received 0 Likes
on
0 Posts
Unfortunately for you...that's a very basic question which won't command a response.
You'll need a vag.com (www.ross-tech.com) in order to log block 115 which contains the aforementioned values. Take a full throttle run in 3rd gear while logging that block from 2K rpms on up to 5K+rpms.
Plot the resulting logs in a graph and look for significant deviation (indicating the ECU is requesting boost, but the actual values differ greatly).
A simpler way would be to hook up a boost guage (fuel pressure regulator has a vac line you can run a "T" fitting off of), record peak readings, and compare them to "the norm" for the level of modification your car has.
Plot the resulting logs in a graph and look for significant deviation (indicating the ECU is requesting boost, but the actual values differ greatly).
A simpler way would be to hook up a boost guage (fuel pressure regulator has a vac line you can run a "T" fitting off of), record peak readings, and compare them to "the norm" for the level of modification your car has.
Thread
Thread Starter
Forum
Replies
Last Post
SilverisFaster
S4 / RS4 (B5 Platform) Discussion
4
01-17-2002 07:30 PM
chisilvertip
TT (Mk1) Discussion
2
05-02-2001 11:40 AM