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Discussion Starter · #1 ·
So I bought Jetta and it had sat for 7 months and I needed a car so I wanted to work on it. My mechanic tried to put some fuel into the fuel filter to see if it would start but has trouble getting fuel In general. Could it be the injector pump isn’t primed or a bad pump?
 

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So I bought Jetta and it had sat for 7 months and I needed a car so I wanted to work on it. My mechanic tried to put some fuel into the fuel filter to see if it would start but has trouble getting fuel In general. Could it be the injector pump isn’t primed or a bad pump?
Could be your lift pump in the fuel tank. When you turn the key to the "on" position prior to starting you should hear the pump run momentarily. If you don't hear it run it is not working. Before removing it be sure to check the fuses! There is an access cover under the rear seat on the passenger side which has to be removed before you can get at the lift pump.
 

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Could be your lift pump in the fuel tank.
A 2000 Jetta with an ALH doesn’t come stock with a lift pump in the tank.
There are a few things that could be wrong. But since it sat for a while there is a possibility that the check valve in the fuel sending / pickup unit isn’t working right. This will let fuel bleed back into the tank from the send line as well as the return.
ALH engines can be fussy if air gets in the lines between the HPFP and the injectors. If you had a bleed back problem, this is a likely result. To fix and diagnose, bleed the injectors. There is a YouTube vid with Kerma doing an injector change and towards the end he demos the bleed process (cracking the line at the injector and cranking till fuel comes out). When you do the bleed you’ll be able to tell if fuel is getting to the injectors.
Also put a hand vacuum pump on the feed line to the fuel filter and make sure fuel is flowing to the filter.
Let us know how you make out!
 

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I should add that when I said “to fix / diagnose” the diagnose part is: if you don’t have fuel flowing to the injectors after trying to bleed then you still have a delivery problem. If you do have a delivery problem then work the problem on section at a time. Plenty of information out there on using a vac pump to bleed lines and filter
 

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Discussion Starter · #5 ·
I should add that when I said “to fix / diagnose” the diagnose part is: if you don’t have fuel flowing to the injectors after trying to bleed then you still have a delivery problem. If you do have a delivery problem then work the problem on section at a time. Plenty of information out there on using a vac pump to bleed lines and filter
Alright ill be going to work on it saturday so ill update you on the progress
 

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Very interesting have a 98 beetle that ran fine last year when I did a timing belt and I posed a question about fuel delivery. Was not aware of a check valve failure in the sender I bled and vacuumed the injector pump got it running then over night lost fuel again! Have a spare alh engine that I was about to can the injectors and pump. Is there a test for the check valve ie low pressure back to tank and see if it holds? Has anyone tried electric fuel pump as a lift pump? Just wondering. Good luck with your problem will keep an eye on this thread.
 

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Is there a test for the check valve ie low pressure back to tank and see if it holds?
A hand pump that can do pressure as well as vacuum will let you check the line. You shouldn't need much to see if there is a problem. I would check both at the fuel filter side and at the sender to make sure it's happening and the sender is the issue.

Has anyone tried electric fuel pump as a lift pump?
Yes, you can add a lift pump sender from a BEW MK4. I think it's only necessary if you have really big injectors / fuel pump mods (but don't trust me on that, talk to the person who is hot rodding your pump). You have to run the wires, fuse and relay from the front. I think idparts sells a kit and has instructions.
 

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Discussion Starter · #8 ·
So I'm pretty sure i found the problem. we brought the car to my uncle's dump truck mechanic since he works on most diesels and he is significantly closer to where i live. we used a mighty vac to prime the fuel system and it was all fine until we tried priming the fuel filter. before we did the filter it was flowing like butter and was almost perfect, but when we got to the filter no fuel was coming out the line to the IJ. after about 5 minutes of hand pumping we decided to take the filter out and see if it had any fuel even in it and low and behold it was dry. so what we are going to do is get a new filter and check valve (since the old filter had a built-in check valve) and we are going to see if that is the problem. ill try to remember to explain everything that happens but in the meantime thanks for all the information
 

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Discussion Starter · #9 ·
So I appears to have found another issue. I watched a video on how to diagnose nose relays on the car and I watched one where it was about the shutoff valve for the injection pump which is relay 109. The video described about how the check engine light and the glow plug light would not pop up if the relay was bad. So I pulled the relay and ordered another one. Hoping this is the issue. I’ll keep y’all updated
 

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Have you checked the 109 relay? You can crank it all day and it will never start as its the main power feed to the ecu. These can go at any time people need to keep a spare relay in the car.

Any problems search TDI Wiki as that covers write ups and forum posts.
This was a response from a moderator that was very helpful in regards to the 109 relay.
 
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