1971 914-4 Frankenstein, w/ 912E 2.0 L-Jet FI? |
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1971 914-4 Frankenstein, w/ 912E 2.0 L-Jet FI? |
mikesjunk |
Dec 20 2015, 05:39 PM
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#1
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Member Group: Members Posts: 71 Joined: 29-November 15 From: goddard, KS Member No.: 19,423 Region Association: None |
Ok so I'm working on a 1971 914-4 which from another thread it appears to have a 75-76 2.0 912E L-Jet FI system on it from the PO.
I have plumbed new fuel lines through out the car, cleaned fuel tank and it has fresh gas. I went through the dual relay and redid it all which I did find one wire on the wrong terminal from the diagram I had. The previous symptom was that it would start and then die when the key was released. So I threw a battery in it and yep that's what it does. It will fire and run momentarily then die. First issue is that I don't hear the fuel pump run. It's currently wired from the original harness with some PO adds ons like a fuse. It is not wired to the dual relay but back into the harness that runs to the relay box. I put a meter on it while testing and didn't ever see any voltage. So to make sure this wasn't the issue I hot wired it to run off the battery while I tested that. But that didn't fix the main issue. Next item is that the ignition switch looks like it's from the movies and has been hot wires. Of course they did it through and around the knee pad so I'm digging into that now. I unwired it so I could remove the knee pad. From the ignition switch area there looks like 4 wires. red, red/black stripe, a black and a gray. The gray one wasn't hooked to anything. (IMG:http://www.914world.com/bbs2/uploads_offsite/www.mikesjunk.com-19423-1450654793.1.jpg) From the harness there were 5 wires. The Black/Yellow and Blue/Yellow weren't hooked to anything. (IMG:http://www.914world.com/bbs2/uploads_offsite/www.mikesjunk.com-19423-1450654793.2.jpg) I'll start researching the wiring diagrams but anyone want to post a response to short cut this would be appreciated. Also the key/cylinder feels pretty bad so anyone recommend someone who can go through it? I saw a guy on ebay listing this but looking for recommendations as it will need something eventually. |
timothy_nd28 |
Jan 3 2016, 04:50 PM
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#2
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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 |
The last test was to help isolate a fuel delivery vs a spark related issue. I was hoping you could of kept the engine running indefinitely with the ether, being that you can't leads me to think you may have a spark related issue. The Ljet ECU uses ground pulses from the points in the distributor to generate a injector firing pattern.
I'm not condemning your fuel injectors. Knowing the spray pattern is good info to help piece this puzzle back together. In addition, the injectors are specific to the ECU, which yours is a 77 or 78 ECU. I wonder if the injectors you have are even compatible with that VW bus ECU? Remove each fuel injector from the intake but leave each fuel injector connected to the fuel rail. Also, try to post the part number stamped on each fuel injector. Then get your fuel pump to activate the way you have been in previous tests. Once you are holding 35 psi of fuel pressure, remove the ECU connector and jump pin 14 to the negative battery post. You should hear a click and fuel spray out from one injector. It would be good to have a catch can under each injector. After pin 14, jump pin 15 then 32 and 33 the same way. Be observant of the spray patterns and report back what you see. **Forgot to mention that you will need to keep 88a and 88b jumpered to the positive battery post while performing this spray pattern test. |
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