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| thatguywiththedatsun |
Mar 21 2014, 01:36 PM
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#1
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Newbie ![]() Group: Members Posts: 21 Joined: 21-March 14 From: Memphis, TN Member No.: 17,144 Region Association: None |
I've been looking for a 914 for a few months now, but life has been in the way. I found one last month that seems to be a good starting point, but I'm having trouble getting it to stay running atm. Seems like it's probably the l-jet system being out of adjustment or leaky, faulty sensors, or some old corroded electrical connectors. The question is; where?
I'm getting a buzzing sound with the key turned to "on" which I initially thought was the seatbelt interlock buzzer everyone seems to be so fond of, but upon closer inspection... it's coming from the injectors..? If i unplug the noisy injector, another one starts buzzing. There's no noise from the fuel pump at this time with the key on. The fuel pump relay, and power supply relay on the board were nowhere to be found when I got the car. I went ahead and bought a few new ones to get it back to stock wiring, but I'm really having trouble deciphering the current flow diagrams. (You guys seems to have a reference system to the pins in every connector, or which specific relay you're referencing. Is there a diagram for this somewhere, or are the labels just buried under the grime in this car?) If i hot wire the double relay (86d, 88d?) to the + battery post, the fuel pump will run, but this doesn't change my "start, rumble rumble, die" situation at all. I have a feeling that there is an area in the wiring that has been altered which, if put back to stock, would rectify the problems I'm having... It's just a matter of finding it and fixing it. Any suggestions? What I have done: -compression test: 125,130,90,135 - hoping it will improve pending a valve adjustment? -tested the coil and wires for spark - checks out fine... nice and strong -tested fuel pressure - 43psi holding steady for several minutes after the test (p.o. said he'd recently had the fuel pump replaced, but didn't mention why (IMG:style_emoticons/default/dry.gif) ) -renewed all the l-jet vacuum hoses and put hose clamps on every connection -taken care of a few obvious electrical bugs (missing/rusty relays, broken wires, etc) -checked the head temp sensor spade connection, but where does the other end of that connection terminate on the relay board? -checked afm resistance. - With key on, if I move the flap by hand, the fuel pump does run, but there is no 1.5 seconds of priming with the key on, just the annoying injector buzz. Thanks in advance for the help! I'll be much better off if someone could just explain the 'pin 13/relay 74/etc. references to me. (IMG:http://www.914world.com/bbs2/uploads_offsite/lh5.googleusercontent.com-17144-1395430598.1.JPG) (IMG:http://www.914world.com/bbs2/uploads_offsite/lh5.googleusercontent.com-17144-1395430599.2.JPG) (IMG:http://www.914world.com/bbs2/uploads_offsite/lh3.googleusercontent.com-17144-1395430600.3.JPG) (IMG:http://www.914world.com/bbs2/uploads_offsite/lh3.googleusercontent.com-17144-1395430600.4.JPG) |
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| thatguywiththedatsun |
Mar 23 2014, 01:43 AM
Post
#2
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Newbie ![]() Group: Members Posts: 21 Joined: 21-March 14 From: Memphis, TN Member No.: 17,144 Region Association: None |
3.5k ohms
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thatguywiththedatsun 1.8 l-jet fires, but dies within seconds Mar 21 2014, 01:36 PM
Chris H. Timothy_nd28 is the man you need to speak to, and ... Mar 21 2014, 01:47 PM
timothy_nd28 The injector buzzing sound is very intriguing to m... Mar 21 2014, 02:14 PM
Cap'n Krusty Unplug all of the injectors. Key on, plug them ba... Mar 21 2014, 02:28 PM
thatguywiththedatsun I'll be in the garage in the next few hours, a... Mar 21 2014, 02:30 PM
thatguywiththedatsun Email address is xxxxxxxxxx@gmail.com. One chance ... Mar 21 2014, 02:31 PM
timothy_nd28 2 manuals sent to your email address. I would re-... Mar 21 2014, 02:38 PM
Dave_Darling Here's a link to a diagram of the FI wiring ha... Mar 21 2014, 04:17 PM
thatguywiththedatsun Very useful tests! What I originally thought w... Mar 21 2014, 08:09 PM
thatguywiththedatsun Wait a minute.... You said pin 13 to ground. Lol, ... Mar 21 2014, 08:49 PM
timothy_nd28 Yep, pin 13 on the ECU plug to engine ground. The... Mar 21 2014, 09:45 PM
thatguywiththedatsun Man, you are good with this stuff. I'll try to... Mar 21 2014, 09:57 PM
69telecaster While I don't really like Rivieras, that car l... Mar 22 2014, 07:40 AM
jim_hoyland All the above info is very useful; I have on occas... Mar 22 2014, 12:21 PM
thatguywiththedatsun Interesting. I read 0V on 14 and 15, and I have no... Mar 22 2014, 06:57 PM
thatguywiththedatsun I'm not crazy about the weird cloth seats myse... Mar 22 2014, 07:08 PM
Jeff Bowlsby That's a standard 1974 1.8L FI harness. You c... Mar 22 2014, 08:53 PM
thatguywiththedatsun Man, I'm stupid. Okay, after testing the corre... Mar 22 2014, 11:00 PM
malcolm2
Man, I'm stupid. Okay, after testing the corr... Mar 23 2014, 10:00 AM
timothy_nd28 Good, what was your reading from pin 13 to engine ... Mar 23 2014, 12:51 AM
timothy_nd28 Great, just wanted to verify that you weren't ... Mar 23 2014, 09:30 AM
davesprinkle Oh yeah, the old "leave the AFM disconnected... Mar 23 2014, 12:41 PM
Chris H. Yep met too. Runs terrible with that thing off do... Mar 23 2014, 12:46 PM
davesprinkle
Yep met too. Runs terrible with that thing off d... Mar 23 2014, 03:02 PM
thatguywiththedatsun
[quote name='thatguywiththedatsun' post='2014655'... Mar 23 2014, 05:55 PM
malcolm2
That's my problem... I don't have the fa... Mar 24 2014, 08:32 AM
thatguywiththedatsun All injectors fire a nice even spray pattern with ... Mar 23 2014, 06:55 PM
timothy_nd28 So far so good. Now with your multimeter set to o... Mar 23 2014, 11:16 PM
jim_hoyland As an aside: By grounding # 1 ( forward left spade... Mar 24 2014, 07:06 AM
thatguywiththedatsun No buzzing from the injectors during the spray tes... Mar 24 2014, 06:48 PM
timothy_nd28 How far away do you live from Clark? It would be ... Mar 24 2014, 06:57 PM
malcolm2
How far away do you live from Clark? It would be... Mar 24 2014, 07:53 PM
thatguywiththedatsun Not sure. I'm in Memphis. I did see a '74 ... Mar 24 2014, 07:23 PM
timothy_nd28 If it can be had for under 5 bucks, maybe. Mar 24 2014, 07:24 PM
timothy_nd28 Pin 6 and 9 on the ECU plug show the total resista... Mar 24 2014, 09:32 PM
malcolm2 Tim, did you give him the ITINERANT link?
http://... Mar 24 2014, 09:44 PM
timothy_nd28 Black22 found that link, all good stuff. :beer2: Mar 24 2014, 10:08 PM
thatguywiththedatsun Oohlala. Definitely my cup of tea. I'll probab... Mar 25 2014, 12:54 PM
thatguywiththedatsun No dice, gentlemen. Got the afm responding reasona... Mar 28 2014, 05:16 PM
Valy I bet it dies because the fuel is cut at the injec... Mar 28 2014, 05:37 PM
timothy_nd28 Okay, so some further tests you can do. On the (+... Mar 28 2014, 07:42 PM
timothy_nd28 One last test, in addition to pin 88d being jumped... Mar 28 2014, 08:03 PM
malcolm2 so what ever happened here? Did you buy a new AFM... Apr 20 2014, 09:34 AM
thatguywiththedatsun Once again, other stuff got in the way. I'm po... May 2 2014, 02:24 PM
thatguywiththedatsun Bought a rebuilt afm from fuel injection corp. Sam... Mar 12 2015, 08:00 PM
thatguywiththedatsun Bringing a thread back from the dead here I know, ... Feb 22 2017, 02:07 AM
Tjmrfe
Bringing a thread back from the dead here I know,... Feb 23 2017, 05:14 PM
Root_Werks ECU failure is uncommon....used to be. Maybe as t... Feb 24 2017, 09:09 AM![]() ![]() |
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