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Sat Nov 15, 2008 7:18 am

So I was recently coming home from a weekend climbing trip with my 84 vanagon. It was a 3 hour drive both ways. The van drove great the whole weekend.... on the drive home, about 20 miles from home, I was coming up a small hill on the highway, and the power all but vanished. The van really started dragging ass. The fuel gauge read 1/8 of a tank.
So I'm wondering if maybe some shite from the gas tank maybe go sucked up into the fuel line or filter.
I drove it yesterday for the first time since the trip and it was really dragging .

Any suggestions??

Sat Nov 15, 2008 7:29 am

You could do a fuel delivery quantity test to see if enough fuel is passing through the system. This would be free other than your time.

Or you could start replacing things and see if it gets better. That would probably cost money and time.

Mark

ptbarnum wrote: So I was recently coming home from a weekend climbing trip with my 84 vanagon. It was a 3 hour drive both ways. The van drove great the whole weekend.... on the drive home, about 20 miles from home, I was coming up a small hill on the highway, and the power all but vanished. The van really started dragging ass. The fuel gauge read 1/8 of a tank.
So I'm wondering if maybe some shite from the gas tank maybe go sucked up into the fuel line or filter.
I drove it yesterday for the first time since the trip and it was really dragging .

Any suggestions??

Sat Nov 15, 2008 7:31 am

Probably time for full diagnostic testing. Hard to convince yourself to do it sometimes, but very easy to do.

Sat Nov 15, 2008 8:09 am

Thanks for these suggestions, but how do I go about either of them.
Can you do a full diagnostic test on your own.... I have only basic tools?
How do you do a fuel delivery test?

Sat Nov 15, 2008 8:57 am

The short answer is you measure how much fuel the system pumps by unhooking the return line at the tank and running the return hose into a container. Then hot wire the fuel pump for 30 seconds exactly. Then measure how much fuel is in the container. You should get at least 1/2 quart, 16 ounces, in 30 seconds.

To hot wire the fuel pump you need to pull the fuel pump relay out of its socket and look at the legs of it. Find the 2 legs labeled 87 and 30 with tiny numbers. Then stick the ends of a short piece of wire into the relay SOCKET holes where legs 87 and 30 would go. The fuel pump should run as long as you hold the wire there. Don't damage the holes and don't use the wrong holes!

The return line connects to the fuel tank below the van on the drivers side. You may need to plug the fitting on the tank after you pull the hose off. Then put the hose into something like an empty half gallon plastic milk jug, clean and dry is best so you can put the gas back into the tank when you are done. A small plastic water bottle holds 16 ounces so you could use that and have someone hold it in place and time how long it takes to fill it while you jumper the fuel pump on.

NO, you can't do this test on the pump side, only on the return side.

You should also test the pressure but that is a separate step.

Mark

ptbarnum wrote: Thanks for these suggestions, but how do I go about either of them.
Can you do a full diagnostic test on your own.... I have only basic tools?
How do you do a fuel delivery test?

Sat Nov 15, 2008 11:17 am

The diagnostic tests take a voltmeter and a Fuel Pressure gauge, and maybe a compression gauge if you have questions about the overall condition of the engine. The procedure is found in the FI section of the Bentley.

Can't hurt to change the fuel filter. The filter and pump inlet system VW used on the early Vanagons is poorly engineered and clogs easily. You will usually be given a lot of warning by the fuel pump though as it will whine loud and long before it quits pumping enough fuel for the engine to run. Until I changed out the fuel pump inlet system on my 83 1/2 I carried at least one spare fuel filter in the glove box, more if I was go on a trip.

Sun Nov 16, 2008 11:43 am

so the rain stopped and the cold moved in.
I changed the fuel filter and Its an obvious improvement on the flat but as soon as I start to go up even a small hill I loose power. This is making me nuts, I have someone who maybe able to help me this week do the fuel delivery test, but I'm wondering if there is anything else I can look into today.

Sun Nov 16, 2008 4:14 pm

Cut open that old filter and see if it was full of rust.