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> New to Me 1974 914, Fuel Injection Help Plz
Picklesmack
post Jul 29 2013, 08:48 PM
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I have purchased a 1974 914 with a L fuel injection system. Cleaned out fuel tank and topped off tried to start it, got plenty of spark. Checked fuel lines and the lines were backwards..pump line going the wrong way, pulled the lines out to make sure what line was coming from the fuel pump and the motor fired right up and was running..shut motor down put fuel lines in the proper connections..and cranked motor..no fire back up...vacuum lines are a mess on the thing would like to eliminate what I can. Help with any info please?

p.s. extra info..the car has been sitting behind a garage for about the last year and this is its first startup I believe
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r_towle
post Jul 29 2013, 08:58 PM
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Ljet won't run if there are any vacuum leaks, so you need to fix all of them.
Vacuum lines are obvious.
Large rubber tube that connects to the AFM can have cracks, check it.
Fuel injectors have rubber o rings, replace them.


Rich
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Picklesmack
post Jul 29 2013, 09:09 PM
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QUOTE(r_towle @ Jul 29 2013, 10:58 PM) *

Ljet won't run if there are any vacuum leaks, so you need to fix all of them.
Vacuum lines are obvious.
Large rubber tube that connects to the AFM can have cracks, check it.
Fuel injectors have rubber o rings, replace them.


Rich

Is there any way to eliminate any of them? or is that system rely on the vacuum? Seemed totally odd to me to unhook the fuel and the thing fired up and was running..
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Picklesmack
post Jul 29 2013, 09:19 PM
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QUOTE(Picklesmack @ Jul 29 2013, 11:09 PM) *

QUOTE(r_towle @ Jul 29 2013, 10:58 PM) *

Ljet won't run if there are any vacuum leaks, so you need to fix all of them.
Vacuum lines are obvious.
Large rubber tube that connects to the AFM can have cracks, check it.
Fuel injectors have rubber o rings, replace them.


Rich

Is there any way to eliminate any of them? or is that system rely on the vacuum? Seemed totally odd to me to unhook the fuel and the thing fired up and was running..

also do you know of any websites that might have some good schematics of what it should look like with pics maybe? The guy I got it from didn't have them all hooked up and some just dont look like they should go to anything..I am new to the vacuum fuel injections... have mainly dealt with carbs in the past..er present with my 1971 boat..
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Jmedeiros
post Jul 29 2013, 09:55 PM
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porsche 914 vacuum hose diagram <<-- Google this! (IMG:style_emoticons/default/beerchug.gif)
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Picklesmack
post Jul 29 2013, 10:24 PM
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QUOTE(Jmedeiros @ Jul 29 2013, 11:55 PM) *

porsche 914 vacuum hose diagram <<-- Google this! (IMG:style_emoticons/default/beerchug.gif)

Wow..thank you!! ....
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euro911
post Jul 30 2013, 12:26 AM
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Also, check out Jeff Bowlsby's site (914 Tech Notebook). Click here and scroll down to the L-Jet stuff (IMG:style_emoticons/default/idea.gif)

You can't eliminate any vacuum lines. Check all the hose ends for cracking. If it appears that there is enough slack, you can try snipping a little (1/4" to 1/2") off the ends (past any cracks). I would recommend replacing them if they'll be too short or if they are just plain 'old' (dry, hard, brittle, etc.).

Also, (IMG:style_emoticons/default/welcome.png)
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Cap'n Krusty
post Jul 30 2013, 08:48 AM
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PM me an email address that'll accept large files and I'll send you a PDF of the VW factory troubleshooting guide.

BTW, there are TWO oil filler cap seals and you MUST have both installed and intact. I recommend having a spare set on hand. I think Pelican Parts has them, if not OE, then replicas.

The Cap'n
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Picklesmack
post Jul 30 2013, 08:39 PM
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QUOTE(euro911 @ Jul 30 2013, 02:26 AM) *

Also, check out Jeff Bowlsby's site (914 Tech Notebook). Click here and scroll down to the L-Jet stuff (IMG:style_emoticons/default/idea.gif)

You can't eliminate any vacuum lines. Check all the hose ends for cracking. If it appears that there is enough slack, you can try snipping a little (1/4" to 1/2") off the ends (past any cracks). I would recommend replacing them if they'll be too short or if they are just plain 'old' (dry, hard, brittle, etc.).

Also, (IMG:style_emoticons/default/welcome.png)

Thank you!! I ordered a vacuum hose kit today, should get it tomorrow and dig in. Thank you again very much and hopefully will have it running soon
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Picklesmack
post Aug 4 2013, 07:27 AM
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This is a picture of where I am at. I redid the vacuum lines and spark plugs gave it a crank and it started for a min.. Kinda chuga chuga almost kept running then died. Couldn't get it to recreated that again. I checked firing order and all that is good. My next step is to take out the injectors and check the and put in a new distributor condenser. Am I heading in the right direction and how could I check the functionality of the injectors when I get them out? Thank you for all your help so far


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Cap'n Krusty
post Aug 4 2013, 08:01 AM
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"Condenser"? They almost NEVER fail. Ever. If you insist on replacing it, use ONLY the Bosch part correct for the application. There are several, and the parts store books are frequently wrong, so be careful what you buy. Looks like it should be "02 074". Look at the points while you're in there. )1 011 should fit. Gap to .016", set the dwell to 47 +/- 3 degrees (go for the "-" side, 45 or so), timing is set at 900 RPM, engine warmed up, hoses off and plugged, to the red line. Reconnect the hoses, adjust the idle with the air bypass screw. The ignition system is not your problem, though, so doing all this is a waste of time 'till you fix what's really wrong, and you may just make things worse.

The Cap'n.
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type47
post Aug 4 2013, 08:14 AM
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QUOTE

... and how could I check the functionality of the injectors when I get them out?


Remove the injectors from the intake runners; easy to remove: 6mm nuts and gently pull from runner. Then locate the injector over a small container that will hold the gas that (hopefully) will squirt into the container when you turn the engine over. For safety sake, disable spark (I think just remove the coil to dizzy wire). When you engage the starter by turning the key, you should, theoretically, get fuel squirting out of the injector. There is another way of doing this by bridging terminals in the ECU plug; I have done this on an L-Jet Vanagon which should be the "same" as an L-Jet 914. Actually, you could do the "bridge on the ECU plug" with the injectors still mounted but all you will get is a click of the injector and not see if it squirts gas.
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Dave_Darling
post Aug 4 2013, 09:12 AM
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If it runs with the fuel pump unplugged (however briefly), that may mean that it was getting way too much fuel before.

Look for unplugged wires, especially near the #3 spark plug on the right-hand side of the engine. There's a single wire that comes out of the engine tin there, and if it isn't plugged in the mixture will go so rich that the engine won't run.

--DD
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timothy_nd28
post Aug 4 2013, 10:17 AM
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I like to know what the fuel pressure is at starting and again when running.
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Cap'n Krusty
post Aug 4 2013, 04:46 PM
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QUOTE(Picklesmack @ Jul 29 2013, 07:48 PM) *

I have purchased a 1974 914 with a L fuel injection system. Cleaned out fuel tank and topped off tried to start it, got plenty of spark. Checked fuel lines and the lines were backwards..pump line going the wrong way, pulled the lines out to make sure what line was coming from the fuel pump and the motor fired right up and was running..shut motor down put fuel lines in the proper connections..and cranked motor..no fire back up...vacuum lines are a mess on the thing would like to eliminate what I can. Help with any info please?

p.s. extra info..the car has been sitting behind a garage for about the last year and this is its first startup I believe


Wait a minute. Tell me the part about swapping out the fuel lines again. I'm not clear what you did. The CENTER hose from the fuel pump goes to the right fuel rail. From there the line goes across the top of the engine via the cold start valve and into the left fuel rail. Next stop is the fuel pressure regulator, and then on to the right side of the engine compartment and connects to the tube that goes to the "Y" next to the fuel pump. The "Y connects the pressure relief (return) fitting on the pump and the return line to the tank.

The Cap'n
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ConeDodger
post Aug 4 2013, 06:12 PM
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(IMG:style_emoticons/default/welcome.png)
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Picklesmack
post Aug 10 2013, 03:16 PM
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QUOTE(ConeDodger @ Aug 4 2013, 08:12 PM) *

Thank you!!
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Picklesmack
post Aug 10 2013, 03:17 PM
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QUOTE(Dave_Darling @ Aug 4 2013, 11:12 AM) *

If it runs with the fuel pump unplugged (however briefly), that may mean that it was getting way too much fuel before.

Look for unplugged wires, especially near the #3 spark plug on the right-hand side of the engine. There's a single wire that comes out of the engine tin there, and if it isn't plugged in the mixture will go so rich that the engine won't run.

--DD

I don't see any unplugged wires..but will clean up the conx and see
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Picklesmack
post Aug 10 2013, 03:21 PM
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QUOTE(Cap'n Krusty @ Aug 4 2013, 06:46 PM) *

QUOTE(Picklesmack @ Jul 29 2013, 07:48 PM) *

I have purchased a 1974 914 with a L fuel injection system. Cleaned out fuel tank and topped off tried to start it, got plenty of spark. Checked fuel lines and the lines were backwards..pump line going the wrong way, pulled the lines out to make sure what line was coming from the fuel pump and the motor fired right up and was running..shut motor down put fuel lines in the proper connections..and cranked motor..no fire back up...vacuum lines are a mess on the thing would like to eliminate what I can. Help with any info please?

p.s. extra info..the car has been sitting behind a garage for about the last year and this is its first startup I believe


Wait a minute. Tell me the part about swapping out the fuel lines again. I'm not clear what you did. The CENTER hose from the fuel pump goes to the right fuel rail. From there the line goes across the top of the engine via the cold start valve and into the left fuel rail. Next stop is the fuel pressure regulator, and then on to the right side of the engine compartment and connects to the tube that goes to the "Y" next to the fuel pump. The "Y connects the pressure relief (return) fitting on the pump and the return line to the tank.

The Cap'n

Yes the fuel is pumping in and out of the "right to left" lines ..I didn't check the fuel pump visually as it had no problem pump fuel from one side of the pit to the other.. I will check the return lines though and am gonna check the nozzles and replace o rings on fuel spitters
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