Bleeding Fuel System
- Thread starter mark21
- Start date
newtdidave
Well-known member
I find injectors easy, Just loosen one till fuel spurts out, then move to the next one. When the first 2 injecter lines our bled, it should start sputtering, making #3 and #4 lines a joke. I just don't know the best way for the Injection pump.
I have tried everything to get the car to start with no luck. It has been 2 hours now of figuring everything out.
What I know:
-The injectors are getting fuel because when cracked they have a nice stream out of each.
-it cranks....haha
What I know:
-The injectors are getting fuel because when cracked they have a nice stream out of each.
-it cranks....haha
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Generally, just cause fuel come out a loosened injector line at the injector, doesn't mean its good to go. Any air still in the lines will only compress and the engine will not start.
So, make sure the bled process is complete........... crank the engine long enough to "flush-out" all the air!
If everything else about the engine is okay, it should fire right up!
So, make sure the bled process is complete........... crank the engine long enough to "flush-out" all the air!
If everything else about the engine is okay, it should fire right up!
sullyTDI
Veteran Member
mighty vac the fuel filter till you get fuel, crack all 4 injectors, turn it over a good bit, enough to cycle out enough fuel to clear all the air, tighten the injectors an fire it up.....
give this a view too: http://www.cincitdi.com/videos/fuelfilter.html
give this a view too: http://www.cincitdi.com/videos/fuelfilter.html
Sip'n Diesel
Veteran Newbie
Yes old post... but I ran my audi a3 tdi out of fuel last week (gauge said 40 miles till empty). I know I should have known better since the car gets 40 - 55 mpg depending on my driving.
Anyway I am posting this as information because I Google and youtubed for hours and found all of these type solutions to be completely useless. Vacuum pumps don't work very well in my experience and did not work in this situation either.
What did work for me was to hook wires to the electric fuel pumps (both of them) and run them at the same time. I used coat hangers and jumper cables because that is what I had with me.
Remove the rear seat
Remove the plug from the fuel pump
Connect wires to the pump ground and hot pins, they are the two on the outside with the largest wire (brown wire is ground, hot is the other outside wire color varies) I just rested the tip of coat hangers on top of the pins and clamped the coat hangers into jumper cables.
The other pump is on the left side by the fuel filter.
With one hand hook a coat hanger around the positive battery terminal and touch the tip of the positive terminal of the second fuel pump
With the other hand complete the circuit for the 1st fuel pump with jumper cables on the battery.
Let these two pumps run simultaneously until the sound changes and you can tell there is no air. You could also insert a clear line on the return to see there is no air.
This took 5-30 seconds.
Next remove the fuel return hose and plug both ends.
Then completely unscrew the closest fuel injector nut
Slightly release the tension on the injector line with one hand and run the pump in the engine bay until fuel comes out (a couple seconds at most)
Tighten the nut back on the injector
Repeat for all 4 injectors
Put the fuel return line back on
Start the car...my car started in 2 cranks.
This will put much less wear on your starter battery and fuel system than these other suggestions about cranking the engine over to prime it. I tried the other methods and ended up draining the battery and having to recharge overnight
Anyway I am posting this as information because I Google and youtubed for hours and found all of these type solutions to be completely useless. Vacuum pumps don't work very well in my experience and did not work in this situation either.
What did work for me was to hook wires to the electric fuel pumps (both of them) and run them at the same time. I used coat hangers and jumper cables because that is what I had with me.
Remove the rear seat
Remove the plug from the fuel pump
Connect wires to the pump ground and hot pins, they are the two on the outside with the largest wire (brown wire is ground, hot is the other outside wire color varies) I just rested the tip of coat hangers on top of the pins and clamped the coat hangers into jumper cables.
The other pump is on the left side by the fuel filter.
With one hand hook a coat hanger around the positive battery terminal and touch the tip of the positive terminal of the second fuel pump
With the other hand complete the circuit for the 1st fuel pump with jumper cables on the battery.
Let these two pumps run simultaneously until the sound changes and you can tell there is no air. You could also insert a clear line on the return to see there is no air.
This took 5-30 seconds.
Next remove the fuel return hose and plug both ends.
Then completely unscrew the closest fuel injector nut
Slightly release the tension on the injector line with one hand and run the pump in the engine bay until fuel comes out (a couple seconds at most)
Tighten the nut back on the injector
Repeat for all 4 injectors
Put the fuel return line back on
Start the car...my car started in 2 cranks.
This will put much less wear on your starter battery and fuel system than these other suggestions about cranking the engine over to prime it. I tried the other methods and ended up draining the battery and having to recharge overnight
keaton85
Veteran Member
That would help if it pertained to the vehicle that this topic is about. Two different systems!
LawrenceMathon
Member
confused
In your explanation here, are you referring to the engine running when you loosen each injector one at a time, because if there is air in those fuel lines between the injection pump and the injector, the car won't run - period.
UhOh
Top Post Dawg
Lawrence, that post that you're responding to is almost 5 1/2 years old!
You crack an injector and then crank. The injector will spew fuel, eventually. Tighten and do the next one. If at any time the engine starts, then STOP cracking injectors as there's no longer any need to since the engine is running!
You crack an injector and then crank. The injector will spew fuel, eventually. Tighten and do the next one. If at any time the engine starts, then STOP cracking injectors as there's no longer any need to since the engine is running!
Rembrant
Veteran Member
That's about the simplest way to put it, isn't it? If the engine starts, stop cracking the injectors nuts! Maybe I've just been lucky, but in the handful of times that I've had to do this, I've just cracked the one nut on the first injector. A couple cranks and fuel spurts out. Tighten nut, and a couple more cranks and the engine starts.
UhOh
Top Post Dawg
I'd never had any real problems up until I swapped out all the injectors on the daughter's wagon. Took quite a bit of cranking, but holding to the procedure it eventually fired up. It was after dusk and I was tired; this is usually when you end up doing something stupid and making a big problem for yourself!
lovetogo
Member
2006 jetta 1.9
Hey guy's, thanks for add. My neighbor sold me his 2006Jetta tdi with the 1.9, He told me leaving work the car didn't start, after many attempts it did fire. He drove it 5 ml's home then wouldn't restart, He did a fuel pressure test on pick up pump. Tested good. for some reason was on able to test pressure pump at eng. what I have done in the week I have owned the car, being he had the valve cover off. And there was some dip on one of the followers, I replaced the cam & followers with a colt cam set . after putting everything back together. tried starting, and the darn starter sounds like it's falling apart, it grabs once & awhile turning eng over but will not start. I'm thinking I need to start with replace the battery, pull the starter and check it out , and bleed the fuel system. This car has some hail damage, great looking interior , after paying 1.200 for the car, then put out 1125, for the cam kit , sounds like it needs a starter, & a new batter, and a set of tires . For now I need help on bleeding the fuel system , Thanks for all help
Hey guy's, thanks for add. My neighbor sold me his 2006Jetta tdi with the 1.9, He told me leaving work the car didn't start, after many attempts it did fire. He drove it 5 ml's home then wouldn't restart, He did a fuel pressure test on pick up pump. Tested good. for some reason was on able to test pressure pump at eng. what I have done in the week I have owned the car, being he had the valve cover off. And there was some dip on one of the followers, I replaced the cam & followers with a colt cam set . after putting everything back together. tried starting, and the darn starter sounds like it's falling apart, it grabs once & awhile turning eng over but will not start. I'm thinking I need to start with replace the battery, pull the starter and check it out , and bleed the fuel system. This car has some hail damage, great looking interior , after paying 1.200 for the car, then put out 1125, for the cam kit , sounds like it needs a starter, & a new batter, and a set of tires . For now I need help on bleeding the fuel system , Thanks for all help
Last edited:
2001BeetleNM
Member
If my beetle tdi 1.9 2001 is running but intermittently doesn't start, like when I filled up the tank yesterday. My hypothesis is that there was air in the fuel line. Can you crack the injector bolt to bleed air when the car is running?
Some background: During winter my diesel fuel pump leaked but now with plus 100 degree heat the fuel pump is not leaking so I will keep using it. Drove 500 miles with no leaking, but when I filled up gas half way the car was acting like it had air in the fuel lines. It wouldn't start for 5 minutes then it started and keeps starting. So I want to try and bleed air to be sure but can you do that with the car running? Can we crack those injector nuts quickly while the car is running to purge remaining likey small amounts of air? Thanks for any incite.
Some background: During winter my diesel fuel pump leaked but now with plus 100 degree heat the fuel pump is not leaking so I will keep using it. Drove 500 miles with no leaking, but when I filled up gas half way the car was acting like it had air in the fuel lines. It wouldn't start for 5 minutes then it started and keeps starting. So I want to try and bleed air to be sure but can you do that with the car running? Can we crack those injector nuts quickly while the car is running to purge remaining likey small amounts of air? Thanks for any incite.
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
If it is running (smoothly) there is no air to bleed out. If it is idling rough, well, there could be a number reasons, including air which will clear out in short order assuming there isn't more coming in upstream in the system.
You need to clean all the accumulated curd off the IP........ soap (Dawn) and water and a thorough rinse. If you have compressed air, blow it off. If not, allow it to dry for about a half hour. Then, start the engine and observe where the IP is leaking. If the leak is the typical top and next down seals, well, you need to re-seal it. Search for the procedure to do the re-seal. .................... Do not wash the pump if it is hot............ warm is okay.
If the shaft seal is leaking, no doubt re-sealing will likely be out of your pay grade!
Side note: I pressure wash my engines on a regular basis .......... but, I always cover the Alternator! I've never had an issue from pressure washing the engine and I use plenty of soap and water! A clean engine is appealing to work on and you can see the leaks much better.
You need to clean all the accumulated curd off the IP........ soap (Dawn) and water and a thorough rinse. If you have compressed air, blow it off. If not, allow it to dry for about a half hour. Then, start the engine and observe where the IP is leaking. If the leak is the typical top and next down seals, well, you need to re-seal it. Search for the procedure to do the re-seal. .................... Do not wash the pump if it is hot............ warm is okay.
If the shaft seal is leaking, no doubt re-sealing will likely be out of your pay grade!
Side note: I pressure wash my engines on a regular basis .......... but, I always cover the Alternator! I've never had an issue from pressure washing the engine and I use plenty of soap and water! A clean engine is appealing to work on and you can see the leaks much better.
2001BeetleNM
Member
I'll definitely give the engine a cleaning. Yes the engine ran rough and then self corrected then ran smooth. But I did notice the diesel leaking again from the injection pump. Unfortunately I cannot clearly tell where the leak is coming from. But why do you think the car wouldn't start for 5 minutes then as I'm calling for help I tried one more time and it started? I had just filled up the gas tank but only half way.
All fuel lines need to be replaced. They are old and cracking. Besides just having the car internitebly not start, is the a vacuum test or some kind of test that can be performed to know for sure there are ot leaks in fuel system?
I suspect air is getting in either through a crack in the fuel line or the injection pump seal that seems to be failing. When I first discovered the injection pump was leaking the car was idling rough. It had just turned to cold weather and the car struggled to start. Oh ya, glow plug light is on too. Probably another thread but it is all connected to the fuel system.
Thanks for the information! Hoping it's not that bottom seal.
All fuel lines need to be replaced. They are old and cracking. Besides just having the car internitebly not start, is the a vacuum test or some kind of test that can be performed to know for sure there are ot leaks in fuel system?
I suspect air is getting in either through a crack in the fuel line or the injection pump seal that seems to be failing. When I first discovered the injection pump was leaking the car was idling rough. It had just turned to cold weather and the car struggled to start. Oh ya, glow plug light is on too. Probably another thread but it is all connected to the fuel system.
Thanks for the information! Hoping it's not that bottom seal.
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
The injection pump has internal pressure when the engine is running. Under normal circumstances, I'm not sure how long the pressure lingers after the engine is shut-down. If a pump seal(s) is leaking, the pressure is likely to go down rather quick.
The last IP I resealed continued to leak. The leak was the O-ring under that big odd shaped nut between the injector pipes coming off the IP. That nut requires a special socket. Seems I did either a Thread or a Post on how addressed it. I used a 15/16" socket (24mm). The procedure is to grind out every other flat on the six-point socket so that it will fit over the odd shaped nut.
Scroll down to Post # 11 in this link to see how I modified the socket: https://forums.tdiclub.com/index.php?threads/alh-pump-leaking-fix-of-replace.512652/
Yes, I suspect your NB has black fuel hoses to and away from the fuel filter and on over to the IP. The fuel hose going to the IP should be replaced with a clear pipe. The ability to observe that pipe is very helpful in trying to diagnose air getting into the system.
The last IP I resealed continued to leak. The leak was the O-ring under that big odd shaped nut between the injector pipes coming off the IP. That nut requires a special socket. Seems I did either a Thread or a Post on how addressed it. I used a 15/16" socket (24mm). The procedure is to grind out every other flat on the six-point socket so that it will fit over the odd shaped nut.
Scroll down to Post # 11 in this link to see how I modified the socket: https://forums.tdiclub.com/index.php?threads/alh-pump-leaking-fix-of-replace.512652/
Yes, I suspect your NB has black fuel hoses to and away from the fuel filter and on over to the IP. The fuel hose going to the IP should be replaced with a clear pipe. The ability to observe that pipe is very helpful in trying to diagnose air getting into the system.
Lefty
Veteran Member
2001BeetleNM
Member
You are correct AndyBees. All my fuel lines are black. I'm having hard time finding a "clear pipe" to use for replacement. I was hoping to find a kit but the best I found was this clear Teflon tubing in this link below. Do you know anywhere to just buy a kit. Not finding what I need when I Google. Thanks for the information. Iv started the deep cleaning on the engine.
forums.tdiclub.com
A4 Jetta TDI Clear Teflon Fuel Line/Injector Return Line Upgrade...
Fellas, Quite a while back I had issues with the dreaded air-in leakage effecting startability of my TDI. At that time I had the 01M transmission and from what I understand the automatic transmission equipt vehicles didn't offer the clear fuel lines from the fuel filter. Since my fuel lines...
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
If there is a clear retro kit for the NB, I am not aware.
I purchased some clear pipe off eBay over three years ago to use on the ALH in my Vanagon. To this day, it has not deteriorated and has remained clear. I went back as far as eBay would let to see if I could find the name/vendor with no luck.
If you'll PM me a ground mailing address, I'll send you more than enough to go from the Fuel Filter over to the IP.
Considering there is some pressure inside the return hose, if it was leaking, you'd certainly see it.
I purchased some clear pipe off eBay over three years ago to use on the ALH in my Vanagon. To this day, it has not deteriorated and has remained clear. I went back as far as eBay would let to see if I could find the name/vendor with no luck.
If you'll PM me a ground mailing address, I'll send you more than enough to go from the Fuel Filter over to the IP.
Considering there is some pressure inside the return hose, if it was leaking, you'd certainly see it.
2001BeetleNM
Member
Just an update. I ended up taking off the top two layers of the injection pump and replacing those gaskets. For sure they were leaking. I used the hammer mod to increase fuel pressure once everything was reassembled as I monitored everything live with the VCDS. My fuel pressure was at like 1.2 and now it's at 3.6. Like a $30 fix I think. Thanks for getting me in the right direction.
2001BeetleNM
Member
My pump appears to be leaking from the threads of the steel fitting that attaches the fuel pipes to the injection pump. Where the steel fitting screws into the injection pump is where fuel appears. Bottom left one is only leaking. I cleaned it well with soapy water let it dry and thats where the fuel appeared befor and after.
The beetle ran great through the summer but the first day it got cold it struggled to start. I'm guessing it sucked air through that fitting since that is the only place fuel is leaking.
I'm going to try tightening the fitting. Not sure there is a O- ring gasket that needs to be replaced.
I had to fix the upper and lower gasket of the pump to dial it down to this area.
AndyBees
Top Post Dawg
- Joined
- May 27, 2003
- Location
- Southeast Kentucky
- TDI
- Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
There is no O-ring under those fittings.
Break loose the one you think is leaking and then re-tighten it. But, I sort of doubt that's the leak location. In all the years (41) that I've owned and driven VW diesels, I've never had one of those fittings to leak.
My guess is this, the leak is the big O-ring under that odd looking nut/plug in the center. It leaked on my 2003 and drove me nuts trying to figure out where the leak was coming from. I did as you, washed with soapy water, sprayed with brake cleaner, carb cleaner, etc., trying to find the leak. I used a flash light at night to find it.
So, below are pics of what I did...
Below is a close-up of the modified 15/16 inch socket (24mm will work too). Every other flat side of the socket must be ground away to make it round so that it will slide over the odd shaped plug. I used a Dremil and patience. It worked great. The big O-ring should be in the kit.
Break loose the one you think is leaking and then re-tighten it. But, I sort of doubt that's the leak location. In all the years (41) that I've owned and driven VW diesels, I've never had one of those fittings to leak.
My guess is this, the leak is the big O-ring under that odd looking nut/plug in the center. It leaked on my 2003 and drove me nuts trying to figure out where the leak was coming from. I did as you, washed with soapy water, sprayed with brake cleaner, carb cleaner, etc., trying to find the leak. I used a flash light at night to find it.
So, below are pics of what I did...
Below is a close-up of the modified 15/16 inch socket (24mm will work too). Every other flat side of the socket must be ground away to make it round so that it will slide over the odd shaped plug. I used a Dremil and patience. It worked great. The big O-ring should be in the kit.
2001BeetleNM
Member
Thanks AndyBees. I think you are probably correct that its the O-ring leaking and not the fittings. I will redo my test. It takes about 5 second befor in see fuel at that #3 or #4 fitting.
Do you have to take out the injection pump to replace the o-ring? I was reading up on your old post about this and you had removed the pump. It was interesting to see the vaccum pump you made. Bet that is a helpful tool.
Do you have to take out the injection pump to replace the o-ring? I was reading up on your old post about this and you had removed the pump. It was interesting to see the vaccum pump you made. Bet that is a helpful tool.