2003 Passat GLS Wagon emits loud hissing sound

jcriepe
0

Asked by Jul 23, 2010 at 10:25 PM about the 2003 Volkswagen Passat GLS Wagon

Question type: Maintenance & Repair

The sound sounds like high pressured air being released like the air brakes on a tractor trailer, but it goes on for 4 or 5 seconds. It only happens when I start to drive after the car has been fully cooled down. The loud hissing stars after I have driven about 25 yards. What's going on?

1 Answer

Blake Bergeron
35

This is most likely the SAP or (Secondary Air Pump). All VW/Audi cars have the same pump which was installed for emissions starting somewhere in the 90's. On the "newer" ones, the rivets break loose and the pump begins to leak and become VERY loud in some cases. The pump will only turn on immediately when you start the vehicle after it has been parked overnight and it will come on from time to time until the car is fully warmed up. NOrmally it is quiet and you can barely hear or feel it running. All it does is send unburt gas vapors through the intake pipe to make sure they get burned up. THe cost for replacement is high at a mechanic. If you have a few hours and can do the work yourself, check out this VW FORUM SITE for the Do It Yourself. VWVORTEX.COM/Forums. I have fixed one of these pumps and it was very easy to drill out the rivets and reseal the sucker with bolts and locktight. Just getting to the pump and replacing it was the long part. Good luck.

3 out of 3 people think this is helpful.

Your Answer

Add photo

Related Questions

Search Volkswagen Passat Questions

Volkswagen Passat Experts

#1 Tom Demyan
Tom Demyan
Reputation 880
#2 tenspeed
tenspeed
Reputation 720
#3 littlehorn
littlehorn
Reputation 700
View All

Related Models For Sale

Used Volkswagen Jetta"
464 Great Deals out of 32,574 listings starting at $995
Used Honda Accord"
549 Great Deals out of 73,681 listings starting at $1,495
Used Toyota Camry"
932 Great Deals out of 76,354 listings starting at $1,000
Used Nissan Altima"
747 Great Deals out of 83,536 listings starting at $1,200
Used Audi A4"
263 Great Deals out of 11,665 listings starting at $1,500
Used Honda Civic"
465 Great Deals out of 59,582 listings starting at $1,500
Used BMW 3 Series"
1,049 Great Deals out of 41,307 listings starting at $1,350
Used Nissan Maxima"
260 Great Deals out of 25,835 listings starting at $1,500
Used Volkswagen Touareg"
37 Great Deals out of 2,667 listings starting at $2,200
Used Audi A6"
112 Great Deals out of 7,315 listings starting at $2,495
Used Volkswagen GTI"
121 Great Deals out of 7,174 listings starting at $2,495

Used Cars For Sale

2016 Volkswagen Passat For Sale
8,271 listings starting at $19,995
2015 Volkswagen Passat For Sale
32 Great Deals out of 3,750 listings starting at $10,995
2014 Volkswagen Passat For Sale
41 Great Deals out of 1,809 listings starting at $9,999
2013 Volkswagen Passat For Sale
85 Great Deals out of 2,762 listings starting at $7,995
2012 Volkswagen Passat For Sale
48 Great Deals out of 1,371 listings starting at $6,995