Fuel Problems

[colectb]

Hi, earlier I posted a thread on this, but I want to start anew. On startup, even when cold, my car functions perfectly for about 20 seconds. After those 20 or so seconds, It will cut fuel from anywhere between 2000 to 3000 rpm. It does this at idle and at load.

I have heard it is probably a fuel problem and I have:
1)Checked the in-tank pre-filter (100% clean)
2)Changed the main fuel filter on 2 occasions
3)Verified to see that it is not gelling (When I looked in the tank, it was fine, and this still happens when it gets above freezing)
4) Checked for fuel leaks, and have none.

So, I need some opinions. Someone said to install a cheap vaccuum gauge, but I don't know where to put it or what it does. Could these be symptoms of a failing injection pump?

I'm at a major loss because I'm about 80 miles from my shop, and if I can't get this fixed with BASIC tools, I need to trailer it home.

Thank you for your help and patience
-Cole

[rabbitman]

Is the wire on the fuel solenoid vibrating loose?

[arb]

Is the wire on the fuel solenoid vibrating loose?

I have a green indicator lamp on my dash connected at the IP to the stud on top of the solenoid so I know if it is getting power.

[colectb]

The solenoid is fine. So today I took the filter off again and the filter itself isn't getting fuel it seems like. I'm guessing it's clogged in one of the hard lines somewhere, I don't know. I'll try to find a shop that won't charge me $100 to blow them out with compressed air.

Unless it is just a weak IP that isn't pulling fuel.

[arb]

If you have an air leak beteen the IP and the fuel pickup in the tank, you will get the same problem.

[colectb]

Are there any common locations?

[TPW]

If you haven't checked yet, there are some rubber fuel lines that connect the metal lines right next to the fuel tank under the car.  You have to remove the protective plate to see them good.  I replaced them about six years ago when I was looking for an air leak.  The suction line may be collapsing when the IP is pulling fuel through it.  You should be able to observe this line before and while the engine is running.  Good Luck!

[RustyCaddy]

i had a hard fuel line that had some debris lodged in it and internal rust issues.  Found that out by blowing air back into the tank from the filter housing and compared that to how hard it was to move air back through the return line to the tank...which was an easy check.  Actually had a pine needle stuck inside the line at the fitting to the filter along with some plastic that looked to have peeled from the bracket that holds the in-tank filter screen.

5/16"' aluminum fuel line is pretty much a direct replacement to the steel hardline if rust is what the problem turns out to be.

you can get a feel for how well the feed pump is working by how well the pump pulls fuel through the clear plastic line (if you have that) from the filter after blowing out the fuel line from the filter to the tank and the system is repriming.

hang in there

[Rabbit on Roids]

i had a hard fuel line that had some debris lodged in it and internal rust issues.  Found that out by blowing air back into the tank from the filter housing and compared that to how hard it was to move air back through the return line to the tank...which was an easy check.  Actually had a pine needle stuck inside the line at the fitting to the filter along with some plastic that looked to have peeled from the bracket that holds the in-tank filter screen.

5/16"' aluminum fuel line is pretty much a direct replacement to the steel hardline if rust is what the problem turns out to be.

you can get a feel for how well the feed pump is working by how well the pump pulls fuel through the clear plastic line (if you have that) from the filter after blowing out the fuel line from the filter to the tank and the system is repriming.

hang in there

this must be a common problem to oregon VWs. my car had that same problem. drove me nuts looking for it. when i found it, and fixed it, it was a friggen rocket.

[colectb]

I think it was internal rust issues. We took off the line going from the fuel filter to the IP, took a shop-vac, cleaned it really well and put it on blow and stuck it on the gas cap hole. We blew out fuel and there were little rust-coloured pieces all over the top of the fuel filter. I then changed the filter, and it has ran perfectly ever since. If I get any more issues I'd definitely do the Aluminum lines. Thanks everyone for your input!

[Kudagra]

Are there any common locations?

I know you fixed your problem but Ill answer it anyway.

That worthless water separator.

[TPW]

Glad to hear "Old Whitey" is running again.

[GTD.]

Mine goes to start then dies streight away

Hasnt been ran for months since the summer really, just fitted a immobiliser and remote start (Clifford AvantGuard 4 with Intellistart) charged the battery, would start but only run for a seccond before spluttering and dieing, thought it was something to do with the immobiliser on that but theres 12v at the solinoid.

Had a look and theres big air bubbles in the clearlines... I had a bunch of briggs and stratton fuel line clips from work, that I fitted them to the fuel filter pipes as there like the vw coolant hose spring clips. I dont think there clamping the hoses tight enough I have some o clips and the propper pliers to install them I'll give them it a try again tomorrow evening