I'm looking at the workshop manual and it says you just open the engine cover and it is there. I looked all over the exposed fuel rail and can not see any schrader valve cap. The provided diagram is not helpful at all.



If there is not, can anyone recommend the best method and location to run a fuel pressure test?



My issue is cylinder 1 is misfiring 0.5% of the time and the engine is running rough at idle or while driving. There is no trouble codes. I have so far changed all the spark plugs, spark plug wires, removed and inspected the coil pack for any cracks, sprayed water in the dark to check for arcing, removed and double checked the gap for new cylinder 1 spark plug.

 

So the answer is yes, there is one.

The workshop diagram fails to picture the stuff directly above it.

Anyway, so I replaced the fuel filter (original, 18 years old, 80,000 miles) and it fixed the misfire. I took it for a test run and my van now runs much quieter, better acceleration, no more rough running, and starts in 2 cranks instead of 3, It even feels slightly smoother at 70mph. The filter was not badly clogged at all, but I guess even a slightly clogged filter will cause a lot of issues.

But replacing the fuel filter caused a new problem. Before the change it held the fuel pressure perfectly at 28psi for 30 minutes. Now it drops rather quickly and hits 0 within 30 minutes. I guess it is something else to look into.

Also, here is a tip on getting the old filter out. The "easy" part is removing the line coming from the gas tank. The impossible part is removing the line going to the engine. After a lot of frustration I thought about just removing the line at the engine and pulling the whole thing out. But all it took was unclipping part of the line. With this part unclipped you pull it so far that the other clip is even easier to access than the fuel tank one. See the picture below where the fuel line unhooks.

It was a bit difficult to get it back in there. I wedged a small piece of wood between it and the heat shield to push it back in.