Questions and Answers
Jetta Fuel Pressure Regulator
Q. Hello Mr Ciulla, I've been reading a lot of your stuff on About.com, I'm very impressed with everything, I love your site. My question is, it takes me 2 turns of the key, sometimes 3 to start my car. I have a 1995 VW Jetta GL, 2.0 liter, manual transmission, 124,500 miles, fuel injection etc.
I just got a 90,000 mile service tune up done, which I badly needed, since I'm at 124,000. My car runs awesome, after I get started. The autoshop told me I needed a "fuel pressure regulator", to fix my turning of the key twice to start. I'm willing to get it, I just want to get a 2nd opinion. They quoted me $200+ and I've seen them a heck of a lot cheaper than that. Please help me.
Thank you in advance.
A. It does sound like you are losing fuel pressure. Turning the key a couple of times before starting will build it up to the point where the engine will start.
Inside the fuel pump is a check valve that prevents fuel from draining back into the tank and maintain fuel pressure over night, actually fuel pressure will normally be maintained for several days. The fuel pressure regulator is the cork on the other end of the bottle. Either one of these being bad will cause the fuel pressure to drop and make starting more difficult.
It is pretty easy to determine which is bad. What I do is hook up my fuel pressure gauge, start the engine and let it run for a minute to stabilize the fuel pressure. Then I shut the engine off and make sure the pressure does indeed drop. Then I start and run again, shut it off and crimp the fuel return line. If the pressure still drops, I have a bad fuel pump check valve. If it doesn't, then the fuel pressure regulator is bad.
The final test is to build up fuel pressure and crimp both the intake and return lines. If the pressure drops, then I know I have a leaking fuel injector.
I'm sure the mechanic who tested the system did the same thing so it is quite possible the fuel pressure regulator is bad.
