Problems after replacing Fuel Lines

[wyomingriviera]

I finished replacing my fuel lines earlier this week. I used the German Supply kit for my '77 2 liter GD case engine. Pretty much everything went smoothly, until I went to start it. The full details can be found here:
http://www.thesamba.com/vw/forum/viewto ... highlight=

My problem is that the bus will only run for a second or three before dying, like it's running out of gas. I've got a few theories:

1)Bad Fuel Pressure Regulator: I smooshed the sides in a little bit trying to get it out. How fragile are these? I read a post about yellow jackets crawling in, not causing problems

2)Clogged Gas Tank: Could there be rust or other schmutz blocking the gas tank outlet? It ran fine before I drained the tank

3)Electrical Connectors to Injectors: If I shorted out a wire when removing the injector, would that make the bus start, but then die two seconds later?

Would these problems cause the above symptom?

Prior to the fuel line replacement, it's been a solid, easy going bus. What went wrong? Is ignorance bliss? thanks, ---W

[vdubyah73]

Starting up and craping out within a second or 2 is usually a vacuum leak. Check your work and any of the pieces not replaced, like the big rubber intake between the AFM and the throttle valve, often called the "S" boot. Check the elbow on the aux air regulator or "AAR" . Make sure all the connections are tight.

[vwlover77]

I saw Randy in Maine's post on the other site, but no confirmation from you that you checked all those items. Start simple. The common cause for a "start-die" situation is forgetting to plug the big connector back onto the AFM, or a loose air hose connection to the S-boot.

[wyomingriviera]

Thanks for the quick replies: I've checked and rechecked the vaccuum hoses, as well as the electrical plug on the AFM. I had really wished the AAR valve was the culprit, but it was connected.

Could squeezing the Fuel Pressure Regulator break it? How about a weak electrical connection on one injector? Thanks, Will

[Amskeptic]

Thanks for the quick replies: I've checked and rechecked the vaccuum hoses, as well as the electrical plug on the AFM. I had really wished the AAR valve was the culprit, but it was connected.

Could squeezing the Fuel Pressure Regulator break it? How about a weak electrical connection on one injector? Thanks, Will

By the sound of your symptom, you are getting fuel pressure at start through the double relay, then losing it when you release the key. This strongly suggests the connector at the AFM, not only must it be secure, which you established, but all the little blades in the connector must be flush with each other. I see a #36 or a #39 terminal.

You can test by carefully but firmly remove the black rectangular plastic cover on the AFM, turning on the ignition, and moving the wiper arm gently in a CCW direction. You should hear the double relay click and the pump turn on. If it does not, look at the little copper contacts that touch when you move the wiper. These are responsible for turning on the fuel pump after the starter releases. If they touch, then you have a wiring issue most likely the above scenario. You can easily peel back the boot and re seat any terminals that have slipped. Install the connector with your fingers pushing the wires in the whole time. Reseat the boot, and start the engine.
Colin

(p.s. - you'd really have to dent that regulator to unseat the ball permanently, if the above does not fix the problem i.e. the pump is runs when you advance the wiper) try pinching the return hose under the car with pliers and see if the engine will run longer. Shut it right down within seconds of establishing that the engine will actually run now, you do not want the excessive pressure that this test creates)

[wyomingriviera]

Thanks for all the replies, guys. really good info. Unfortunately for me, I tweaked out a disk in my back last week (again,) and can't bend over to work on the bus. Also unfortunately for me, I am a complete moron, and don't wanna eff up anything more. When I feel a little better, I'll head over to the Porsche shop to see if they know much about the l-jetronic setup.


***EDIT 6/08***my buddy came over and found a vaccuum line disconnected, duh. I swear I checked 'em many, many times, but just needed a second pair of eyes to proofread my work. I do love the easy fixes!