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| Oregon74 |
Jun 2 2013, 08:42 PM
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#1
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
First- without the help of Admin Andy and Timothy nd 28- my 1975 1.8 L jet would not be on the road. Thank you to everyone who helped me.
NEW ISSUE I NEED HELP FINDING- WHY CAN'T THE ENGINE CONTINUE TO RUN? The engine will start. (I was having a problem with the ignition not turning the motor over- but I think I solved it with a fuse and a relay problem). Now, she starts every time, but then stops after a few seconds. It appears either my fuel pump is out or I'm not getting enough electricity to the pump to run it. I have installed a MSN fuel pump. It is high presure and worked perfect out of the box. I put about 2,000 miles on the car before this mystery started. I've checked the in-line fuel filter and it seems fine. (I do live in Southern Oregon where during the winter the area is forced to run oxigenated fuel that is known to cause problems with older cars- but since she starts just fine I think my injectors are ok.) I've pulled the relay apart and all contacts seem to hit just fine. My questions: 1. Could a new fuel pump go bad this fast? 2. If I'm not getting enough electricity, or have a bad end, where in the world do I find the wires in the engine bay? The pump is connected with a brown and a black (ground) wire. 3. Could it still be the relay? Thanks in advance of to everyone who might chip in advice. I am not experienced checking voltages- but am willing to learn. The problem with this car is: I've got the body in great shape, put a new interior kit in, and have thought about selling it to finance either an SC or a motor for my 365c, but I'm really starting to love this little car. Or as my wife calls it: The Hot Wheel. Thanks, JAA Oregon ![]() |
| rick 918-S |
Jun 3 2013, 05:59 AM
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#2
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Hey nice rack! -Celette ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 21,239 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region
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Hmmm... (IMG:style_emoticons/default/idea.gif) If it starts and idles and runs fine I would start checking connections.
Question: when it fails does it just shut off ? or run bad and stumble, miss, back fire and die? I bought a BMW 2002 off the side of the road one day. It wasn't for sale but I had been passing the car for a week and it was sitting about a foot away from the curb and plowed in by a bank of snow. I left a note on the car and the owner contacted me. Seems the car was running fine but died and he couldn't start it. I asked the same question I posted here. The owner said it just died and had been doing it for a couple weeks. He was a collage kid with no resources to keep it going. I met him at the car and bought it on the spot. After the kid left I opened the hood and started digging around. I found that someone had replace the female spade on the power lead to the dizzy. I plugged it back on and discovered the spade was too large and was loose. I deduced the loose terminal had been shorting and finally fell off. So look for the obvious. It could be as simple as a connection or a cracked relay board. With the car running start carefully moving things and see if you can find the fault. If you think it's the fuel pump try bypassing the relay and running it to see if it repeats the issue. 90% of fuel related issues are electrical. Good luck! and BTW: Nice! (IMG:style_emoticons/default/wub.gif) |
| Black22 |
Jun 3 2013, 08:16 AM
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 886 Joined: 1-November 07 From: Creswell, OR Member No.: 8,290 Region Association: Pacific Northwest |
L jet cars will do this when the AFM is not connected or having issues.
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| timothy_nd28 |
Jun 3 2013, 11:19 AM
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#4
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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What a great looking 914, it would be a shame if you sold it. (IMG:style_emoticons/default/poke.gif)
Let's start backwards with this one, to help isolate your issues. You stated that you had taken apart the dual relay for inspection. Go ahead and remove the dual relay from the car. Next, disassemble the relay by removing the protective shell. With the relay's shell removed, reinsert the relay back into the car. Be very careful, without the protective relay shell it can short out if it touches anything metal. Now, with this relay re-installed, we can run a jumper from +12vdc battery post straight with pin 88d on the relay, while the relay is still electrically connected to its sockets. As soon as you apply power to pin 88d, you should hear the fuel pump turn on (either key on or key off). If the pump activates, go ahead and start the car. The car should stay running indefinitely. Again, be very careful and protect the dual relay from shorting out when it's sitting in the engine bay naked! |
| worn |
Jun 3 2013, 11:21 AM
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#5
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Winner of the Utah Twisted Joint Award ![]() ![]() ![]() ![]() Group: Members Posts: 3,560 Joined: 3-June 11 From: Madison, WI and North Bend WA Member No.: 13,152 Region Association: Upper MidWest
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First- without the help of Admin Andy and Timothy nd 28- my 1975 1.8 L jet would not be on the road. Thank you to everyone who helped me. NEW ISSUE I NEED HELP FINDING- WHY CAN'T THE ENGINE CONTINUE TO RUN? The engine will start. (I was having a problem with the ignition not turning the motor over- but I think I solved it with a fuse and a relay problem). Now, she starts every time, but then stops after a few seconds. It appears either my fuel pump is out or I'm not getting enough electricity to the pump to run it. I have installed a MSN fuel pump. It is high presure and worked perfect out of the box. I put about 2,000 miles on the car before this mystery started. I've checked the in-line fuel filter and it seems fine. (I do live in Southern Oregon where during the winter the area is forced to run oxigenated fuel that is known to cause problems with older cars- but since she starts just fine I think my injectors are ok.) I've pulled the relay apart and all contacts seem to hit just fine. My questions: 1. Could a new fuel pump go bad this fast? 2. If I'm not getting enough electricity, or have a bad end, where in the world do I find the wires in the engine bay? The pump is connected with a brown and a black (ground) wire. 3. Could it still be the relay? Thanks in advance of to everyone who might chip in advice. I am not experienced checking voltages- but am willing to learn. The problem with this car is: I've got the body in great shape, put a new interior kit in, and have thought about selling it to finance either an SC or a motor for my 365c, but I'm really starting to love this little car. Or as my wife calls it: The Hot Wheel. Thanks, JAA Oregon ![]() Don't know much about L-Jet but it sounds like the fuel pump is running off the starter circuit and is then supposed to switch over to another power source when you stop turning over the starter. That second power source is not taking over - probably because something thinks that the motor hasn't started. They generally have a circuit that allows fuel to go in when you are turning the key that is independent because you are there turning the key. Then there is a system that doesn't want to pour gas into a car that isn't running. So it has a sensor to make sure it is. |
| timothy_nd28 |
Jun 3 2013, 11:34 AM
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#6
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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First- without the help of Admin Andy and Timothy nd 28- my 1975 1.8 L jet would not be on the road. Thank you to everyone who helped me. NEW ISSUE I NEED HELP FINDING- WHY CAN'T THE ENGINE CONTINUE TO RUN? The engine will start. (I was having a problem with the ignition not turning the motor over- but I think I solved it with a fuse and a relay problem). Now, she starts every time, but then stops after a few seconds. It appears either my fuel pump is out or I'm not getting enough electricity to the pump to run it. I have installed a MSN fuel pump. It is high presure and worked perfect out of the box. I put about 2,000 miles on the car before this mystery started. I've checked the in-line fuel filter and it seems fine. (I do live in Southern Oregon where during the winter the area is forced to run oxigenated fuel that is known to cause problems with older cars- but since she starts just fine I think my injectors are ok.) I've pulled the relay apart and all contacts seem to hit just fine. My questions: 1. Could a new fuel pump go bad this fast? 2. If I'm not getting enough electricity, or have a bad end, where in the world do I find the wires in the engine bay? The pump is connected with a brown and a black (ground) wire. 3. Could it still be the relay? Thanks in advance of to everyone who might chip in advice. I am not experienced checking voltages- but am willing to learn. The problem with this car is: I've got the body in great shape, put a new interior kit in, and have thought about selling it to finance either an SC or a motor for my 365c, but I'm really starting to love this little car. Or as my wife calls it: The Hot Wheel. Thanks, JAA Oregon Ground wires are usually always brown. The black one should be the hot 12v wire |
| Cap'n Krusty |
Jun 3 2013, 11:59 AM
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#7
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Cap'n Krusty ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
What is a "MSN" fuel pump?
Now, on to my tips. You CANNOT have ANY vacuum leaks. The fuel pump is activated by the flap in the airbox. Pull the airbox, leaving the wires connected, and move the flap with your finger (key on, engine not running). If the pump runs, you may have found your problem (intake air not going through the airbox). If not, reinstall the air box and continue with the troubleshooting. There are TWO seals on the oil filler cap. They must both be there and in nice condition. No seals, no run. Check all the hose connections, especially the little runner elbow at the AAR. Make sure the valve cover gaskets are good. PM me an e-mail address capable of accepting a largish (16mb) file and I'll send you a PDF of the VW L-jet troubleshooting guide. Make sure the address will accept the file; you get only one chance 'cause I don't have time to fiddle around with this. The Cap'n |
| timothy_nd28 |
Jun 3 2013, 12:03 PM
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#8
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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What is a "MSN" fuel pump? Now, on to my tips. You CANNOT have ANY vacuum leaks. The fuel pump is activated by the flap in the airbox. Pull the airbox, leaving the wires connected, and move the flap with your finger (key on, engine not running). If the pump runs, you may have found your problem. If not, reinstall the air box and continue with the troubleshooting. Thete are TWO seals on the oil filler cap. They must both be there and in nice condition. No seals, no run. Check all the hose connections, especially the little runner elbow at the AAR. Make sure the valve cover gaskets are good. PM me an e-mail address capable of accepting a largish (16mb) file and I'll send you a PDF of the VW L-jet troubleshooting guide. Make sure the address will accept the file, you get only one chance 'cause I don't have time to fiddle around with this. The Cap'n A liberal left leaning pump? (IMG:style_emoticons/default/lol-2.gif) |
| worn |
Jun 3 2013, 02:15 PM
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#9
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Winner of the Utah Twisted Joint Award ![]() ![]() ![]() ![]() Group: Members Posts: 3,560 Joined: 3-June 11 From: Madison, WI and North Bend WA Member No.: 13,152 Region Association: Upper MidWest
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Is the above a reference to my airport designation? |
| Oregon74 |
Jun 4 2013, 09:07 AM
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#10
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
What is a "MSN" fuel pump? Now, on to my tips. You CANNOT have ANY vacuum leaks. The fuel pump is activated by the flap in the airbox. Pull the airbox, leaving the wires connected, and move the flap with your finger (key on, engine not running). If the pump runs, you may have found your problem (intake air not going through the airbox). If not, reinstall the air box and continue with the troubleshooting. There are TWO seals on the oil filler cap. They must both be there and in nice condition. No seals, no run. Check all the hose connections, especially the little runner elbow at the AAR. Make sure the valve cover gaskets are good. PM me an e-mail address capable of accepting a largish (16mb) file and I'll send you a PDF of the VW L-jet troubleshooting guide. Make sure the address will accept the file; you get only one chance 'cause I don't have time to fiddle around with this. The Cap'n jallmand@me.com Thanks Cap'n |
| Oregon74 |
Jun 4 2013, 06:18 PM
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#11
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
Still not finding the problem. No air leaks. Can't be the pump as it does start. All the dash lights go on, so can't be the ignition switch. The relay looks fine, I'll try it again tonight.
It seems the car is getting enough juice to start then (I thought the relay) is not switching from ignition to regular fuel flow. I'm going back in my other 914 world notes. More ideas? I'm game. JAA |
| timothy_nd28 |
Jun 4 2013, 06:35 PM
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#12
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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Both the Captain and I gave you instructions that will help isolate and solve this problem. Feedback is needed from the tests to further evaluate your problem (IMG:style_emoticons/default/poke.gif)
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| r_towle |
Jun 4 2013, 08:41 PM
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#13
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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| r_towle |
Jun 4 2013, 08:46 PM
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#14
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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Unplug the airflow meter
Put an ohm meter between plug 36 and 39 Open the flapper door on the air flow meter while watching the meter Ohm meter resistance should go from infinity to zero when you open the door. This is the running fuel pump contact to activate the fuel pump when the car is running and the flapper door is open. Another simpler way to do this test is to turn the key to run. Open the flapper door and listen for the fuel pump. If no pump, it may be wiring or a fuse or the dual relay. If the air flow meter does not pass the above test with an ohm meter, you need a new air flow meter. |
| Oregon74 |
Jun 4 2013, 09:25 PM
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#15
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
What is a "MSN" fuel pump? Now, on to my tips. You CANNOT have ANY vacuum leaks. The fuel pump is activated by the flap in the airbox. Pull the airbox, leaving the wires connected, and move the flap with your finger (key on, engine not running). If the pump runs, you may have found your problem. If not, reinstall the air box and continue with the troubleshooting. Thete are TWO seals on the oil filler cap. They must both be there and in nice condition. No seals, no run. Check all the hose connections, especially the little runner elbow at the AAR. Make sure the valve cover gaskets are good. PM me an e-mail address capable of accepting a largish (16mb) file and I'll send you a PDF of the VW L-jet troubleshooting guide. Make sure the address will accept the file, you get only one chance 'cause I don't have time to fiddle around with this. The Cap'n Flap good Both seals good AAR- now tight. I thought that might be the problem, but didn't seem to be. Did the hot wire Tim suggested. Will write in his post now. Thanks again for the L-Jet guide A liberal left leaning pump? (IMG:style_emoticons/default/lol-2.gif) |
| Oregon74 |
Jun 4 2013, 09:27 PM
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#16
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
What a great looking 914, it would be a shame if you sold it. (IMG:style_emoticons/default/poke.gif) Let's start backwards with this one, to help isolate your issues. You stated that you had taken apart the dual relay for inspection. Go ahead and remove the dual relay from the car. Next, disassemble the relay by removing the protective shell. With the relay's shell removed, reinsert the relay back into the car. Be very careful, without the protective relay shell it can short out if it touches anything metal. Now, with this relay re-installed, we can run a jumper from +12vdc battery post straight with pin 88d on the relay, while the relay is still electrically connected to its sockets. As soon as you apply power to pin 88d, you should hear the fuel pump turn on (either key on or key off). If the pump activates, go ahead and start the car. The car should stay running indefinitely. Again, be very careful and protect the dual relay from shorting out when it's sitting in the engine bay naked! Once Again Tim, you've got it running. Did all you suggested- carefully- and she is currently running. I followed all the Cap'n suggestions also. Found one potential leak and fixed it. So, now that its "hot wired" whats next? Man I owe you a six pack of something Oregon. |
| Oregon74 |
Jun 4 2013, 09:28 PM
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#17
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Newbie ![]() Group: Members Posts: 44 Joined: 13-October 12 From: Oregon Member No.: 15,035 Region Association: None |
Unplug the airflow meter Put an ohm meter between plug 36 and 39 Open the flapper door on the air flow meter while watching the meter Ohm meter resistance should go from infinity to zero when you open the door. This is the running fuel pump contact to activate the fuel pump when the car is running and the flapper door is open. Another simpler way to do this test is to turn the key to run. Open the flapper door and listen for the fuel pump. If no pump, it may be wiring or a fuse or the dual relay. If the air flow meter does not pass the above test with an ohm meter, you need a new air flow meter. This is great. Will report back. Got it running on a wire fix from Tim. |
| timothy_nd28 |
Jun 4 2013, 09:34 PM
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#18
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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My test was never meant as a permanent fix. I just wanted to rule out a few things. Give me a few minutes, so I can write out the next test procedure.
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| timothy_nd28 |
Jun 4 2013, 09:46 PM
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#19
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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Okay, remove the jumper wire that you installed on pin 88d to the battery. Leave the relay installed, I would like you to install a jumper in a different location to test the Air flow meter fuel contacts. Locate pin 88a on the dual relay, and carefully attach a jumper on that pin to the positive battery post (dual relay still inserted in their connectors). Now, remove the plastic cover on the air flow meter. With your fingers, twist the armature counter clockwise about 45 degree's. You should hear the fuel pump turn on.
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| timothy_nd28 |
Jun 4 2013, 10:20 PM
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#20
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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Unplug the airflow meter Put an ohm meter between plug 36 and 39 Open the flapper door on the air flow meter while watching the meter Ohm meter resistance should go from infinity to zero when you open the door. This is the running fuel pump contact to activate the fuel pump when the car is running and the flapper door is open. Another simpler way to do this test is to turn the key to run. Open the flapper door and listen for the fuel pump. If no pump, it may be wiring or a fuse or the dual relay. If the air flow meter does not pass the above test with an ohm meter, you need a new air flow meter. This is great. Will report back. Got it running on a wire fix from Tim. BTW, store that procedure in your memory banks. If you ever get stuck on the side of the road, jumping pin 88d can limp your car back home. |
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