Touareg: 2005 V8
Join Date: Jun 2010
Location: Port Alto, Texas
Second Vehicle: Old heap
Thanked 1 Time in 1 Post
With 100K on the egg, decided to clean the fuel filter. Two months ago I got home after a 2 hour drive at high speed, unpacked the car and when starting up, car would barely run. Turn off and restarted just fine. So with time on my hands, I wanted to check the system out. First of all I canít believe the fuel rack doesnít have a fuel tap. So with a homemade setup checked fuel pressure. Noted items:
1. Opening the driverís door, primer pump comes on for a short time. Fuel pressure 60 psi. Pressure is checked in. No pressure drop noted, so check valve appears to be working.
2. Start engine and pressure is around 62 psi. To determine if fuel filter is restricting flow, the gauge setup has a pressure release button. Pushing the button, fuel filled a 12 oz. bottle in no time. I figured thereís no way with the engine at full throttle it could use this amount of fuel. Pressure drop was around 3-4 psi.
On other threads, Iíve noted that fuel pressure should be around 55 psi. So do I have a problem here?
So with this known, jumped into filter removal. With filter removed, fuel filter with 100K. Used two cans of carburetor cleaner.
With everything installed, couldnít get any pressure and started asking myself what happened but with benb2376 postís ďlessons learnedĒ when installing the O-ring/cap I also rolled the O-ring off the seated position. So note: lubricate the O-ring and cap and when you get the cap seated hold firmly until you get a couple of screws installed. Due to the filter spring, item 10 on benb2376 attachment, the spring will want to move the cap thus dislodge the O-ring. So with everything back together, opened /closed driverís door. Thought I heard the pump but had no pressure. Closed door and went and got a drink, cause I needed one. Came back opened door and got 40 psi. before the pump shut off. Started engine and pressure went to 62 psi. Hit the pressure release button on the gauge and got a little air. With everything back together, I drove the car to work today.
Another thing I learned is when the engine is cold it runs at a higher RPM and drops when engine is warm. What is noted is that the fuel pressure stays the same. On past cars the fuel regulator would lower fuel pressure during warm up and return to a higher pressure after itís warmed up. So again do I have an issue with the regulator?
Anyway attached some pictures.