Pressure Damper problem??
06-25-2012 | 04:02 AM
#1
Thread Starter
Advanced
Joined: May 2012
Posts: 78
Likes: 0
Pressure Damper problem??
while replacing cracked vacuum hoses in my engine bay I pulled the vac line off the fuel pressure damper and when I did, I noticed it was wet , not the damper itself , the vacuum hose. As in it was wet with gasoline, so I blew it out (the damper which was apparently full) and reattached the hose and started the car for a few minutes, then shut it off and checked the damper again which was once again full of fuel .
my questions are :
1) is this normal?
2) if not , does this mean that the internal diaphragm is shot and I need to replace the damper ?
3) is this dangerous?
my questions are :
1) is this normal?
2) if not , does this mean that the internal diaphragm is shot and I need to replace the damper ?
3) is this dangerous?
06-25-2012 | 09:10 AM
#3
Rennlist Member
Rennlist Site Sponsor
Joined: Jun 2001
Posts: 6,469
Likes: 11
From: Acworth, GA
1) No. The vacuum line is only for safety on the dampeners, to prevent raw fuel from causing an engine fire. The vacuum line ensures that diaphragm failure dumps fuel into the intake system rather than on the engine. On the fuel pressure regulator, the vacuum line also enables the regulator to slightly increase ("trim") fuel flow during WOT (Wide Open Throttle) operation.
2) Yes.
3) Not really very dangerous as in causing an engine fire. It is dangerous in the sense that it will pump raw fuel into the intake manifold, which will:
- Waste fuel.
- Increase engine wear.
- Cause hard starting when hot.
- Cause poor idling.
- Cause emission test failure.
2) Yes.
3) Not really very dangerous as in causing an engine fire. It is dangerous in the sense that it will pump raw fuel into the intake manifold, which will:
- Waste fuel.
- Increase engine wear.
- Cause hard starting when hot.
- Cause poor idling.
- Cause emission test failure.
06-25-2012 | 10:24 AM
#4
Rennlist Member
Joined: Jun 2008
Posts: 4,681
Likes: 64
From: Tasmania, Australia
Just make sure that while the damper diaphragms are allowing fuel through that you DO NOT take the vac line off with the motor running, or you may have a spray of fuel from the port. From that perspective, and if you had a cracked vac line that could allow fuel to leak out on shut down, they can present a safety risk IMO.
If one diaphragm is gone you can bet the others are on the way out too, so it's good practice to replace both dampers and the regulator.
If one diaphragm is gone you can bet the others are on the way out too, so it's good practice to replace both dampers and the regulator.
