Volkswagen's fourth-generation Jetta isn't any another prone to hoover leaks than any other machine -- and probably a portion less than most. On the contrary embryonic failures can and arrange happen, and the eight contrary engines offered with this vehivle hog their detached participation of vacuum lines and implied leak points.
Vacuum vs Boost Leak
Turbocharged engines have been a Jetta staple for many age straightaway and the 2005 Jetta is no exception. Many Jettas left the Wolfsburg works with VW's exceptional 1.8-liter four-cylinder turbo, which changes the air leak equation a bantam bit. With a natural vacuum leak, the engine Testament suck additional air in througha leaking hose -- or, else viable, hose becoming -- and the engine Testament drop slim. Turbocharged engines have pressurized intake tracts, so leaks Testament completion in air blowing absent from the coercion generated under boost.
Leak Detection Pump
Oh, those Germans -- they determine assume of everything. The Jetta depends on engine vacuum to perform dozens of at variance functions, not least of which to function the brake booster and to deal in rogue fuel vapours from leaking absent of the vehivle. It is for these reasons that the Jetta uses a supplemental vacuum pump that speeds vacuum buildup at startup, provides vacuum when called for and helps the pc to detect leaks. The pump kicks on whenever vacuum is lower than it should be; whether the pump runs when the personal computer says it shouldn't, the personal computer Testament trigger a vacuum-leak warning decree.
Vacuum Diagram
All of the Jetta's discrepant engines uses a unique vacuum tube arrangement, and VW was kind enough to assist you -- or their mechanics, anyway --in tracking them down. A sticker that details the location, routing and purpose of every vacuum line on the engine can generally be found on top of the radiator support of every Jetta. Have an assistant briefly start the car, and spray the line where it connects to the engine with a two-second burst of brake cleaner or ether starting fluid. If you hear the engine suddenly rise in rpm after spraying the connection, then you've found your leak. Keep working along the line, spraying every connection until you find the leak. When you get to the end of the line, pick another and start again.
You'll refer to this diagram on a regularly when tracking down leaks; just go by the diagram and check line-by-line till you find the leak.
