No power to injectors again!, Got spark, gas, at a total loss |
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No power to injectors again!, Got spark, gas, at a total loss |
surfdogskier |
Oct 7 2019, 06:22 PM
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#1
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
Oh my gosh!!!! She is back to doing this same thing all over again. I finally got her running . She ran fine one evening, parked her. Next day she would not start. No power to the injectors. I got spark. I got gas in the lines. Fuel pump works like it should. I took the distributor out and cleaned the trigger points to see if that would help. All wires are connected. MPS connected. All vacuum lines connected. I bought a noid light set up and they are definitely not getting power.
What else could it be? Something on the relay board? Bad relay? This car is driving me insane. I am about to go duel carbs and drop this piece of **** fuel injection if I can't get this thing running. |
Mikey914 |
Oct 7 2019, 06:27 PM
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#2
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The rubber man Group: Members Posts: 12,653 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
It injection is the best way to go if you can keep it running. What motor?
All 4 I suspect trigger points. Factory spacing is 23mm |
JeffBowlsby |
Oct 7 2019, 06:51 PM
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#3
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914 Wiring Harnesses Group: Members Posts: 8,490 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
I know you said “all wires” but does that include the three pair of ground wires in the FI harness?
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JeffBowlsby |
Oct 7 2019, 06:52 PM
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#4
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914 Wiring Harnesses Group: Members Posts: 8,490 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Dup post, sorry
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surfdogskier |
Oct 7 2019, 06:52 PM
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#5
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
It injection is the best way to go if you can keep it running. What motor? All 4 I suspect trigger points. Factory spacing is 23mm Sorry about that. 1.7. It is all four. I pulled the trigger points and cleaned them. The 3 wires look to be in good condition and the plug. |
surfdogskier |
Oct 7 2019, 06:54 PM
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#6
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
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JeffBowlsby |
Oct 7 2019, 07:10 PM
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#7
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914 Wiring Harnesses Group: Members Posts: 8,490 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Remove the ECU from the FI harness. Leave the harness plugged into the relay board and turn the key to “on”. Do not crank the engine. Do you get 12V between ground and the ECU connector on the harness, at pins 16 and 24? The cavities are numberd on the ECU plug, look carefully.
If no, any change if you wiggle the harness? |
Mikey914 |
Oct 7 2019, 07:25 PM
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#8
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The rubber man Group: Members Posts: 12,653 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
Check power on 16 and 24 if not possible relay board issue?
I know Brad Mayer 914LTD has them rebuilt at about $200 which is less than I paid when mine went out. |
surfdogskier |
Oct 7 2019, 07:47 PM
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#9
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
I will do that tomorrow and post back.....Thanks for the help.
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914_teener |
Oct 8 2019, 02:50 PM
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#10
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914 Guru Group: Members Posts: 5,197 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
I will do that tomorrow and post back.....Thanks for the help. Ring out the wires on the harness as Jeff suggests. Once you get the harness eliminated I'd seriously consider an electronic distributor like the 123 and never worry about it again. You can always upgrade your motor if you decide to go bigger later and just change the dip switch setting. |
surfdogskier |
Oct 8 2019, 02:50 PM
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#11
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
In order to check the 16 and 24 pin, do I have to take apart the ECU and get inside it? The wire going into it. Can this be checked at the regulator plate?
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JeffBowlsby |
Oct 8 2019, 03:51 PM
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#12
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914 Wiring Harnesses Group: Members Posts: 8,490 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Yes to the first question. No to the second.
Slide the grey plastic cover off the ECU, and pull off the plug. You may be surprised at how easy it is once you do it the first time. |
jim_hoyland |
Oct 8 2019, 04:18 PM
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#13
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Get that VIN ? Group: Members Posts: 9,272 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
Congratulations Lawrence. I loved your 914. Great looking car with just the right attitude. I am sure you will love the 911 and I wish you nothing but the best with it. The 3.0 is a terrific motor and with the limited slip 915 you should have lots of fun. I have flip-flopped back and forth between 911's and 914-6's for the last 40 years. In the end the 914-6 was the winner for me. I may buy an '89 Carrera coupe one of these days if I am around long enough. That is the only 911 I really want to share the garage with the 914-6. Cheers and I hope to see you soon. Michael (IMG:style_emoticons/default/beerchug.gif) What's going on at 16 and 24 ? Power coming inputs ? Or ? |
surfdogskier |
Oct 8 2019, 05:41 PM
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#14
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
Yes to the first question. No to the second. Slide the grey plastic cover off the ECU, and pull off the plug. You may be surprised at how easy it is once you do it the first time. Thanks for clarifying. I looked and thought I had to pry all those clips up and then bend them back.....I will go from there and post back. |
surfdogskier |
Oct 8 2019, 06:21 PM
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#15
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
I do have 12v at 24 and 16.
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IronHillRestorations |
Oct 8 2019, 06:25 PM
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#16
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I. I. R. C. Group: Members Posts: 6,716 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
Just because you cleaned the trigger points, does not make them work.
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IronHillRestorations |
Oct 8 2019, 06:32 PM
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#17
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I. I. R. C. Group: Members Posts: 6,716 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
Just because you cleaned the trigger points, does not make them work.
Where are you in east TN? I'm moving to Charleston, near Cleveland |
JeffBowlsby |
Oct 8 2019, 07:12 PM
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#18
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914 Wiring Harnesses Group: Members Posts: 8,490 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Then you have power to the ECU. Somewhere between the harness plug and the 2 wire injector connectors is the discontinuity. The trigger points initiate the voltage pulse to the injectors. The ECU processes the several engine sensors to determine the pulse width. No power to the injectors at idle could be worn out trigger points, a bad ECU, disconnected injector grounds, bad harness wiring. Maybe more. I would check the trigger points as has been mentioned, use an ohmmeter. Pull the dizzy, or check it in the car while cranking. You are looking for alternating continuity between the center pole and each of the two outer poles as the diz is rotated. No continuity, no pulse, no voltage, noid light no worky.
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surfdogskier |
Oct 8 2019, 07:26 PM
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#19
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
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surfdogskier |
Oct 8 2019, 07:29 PM
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#20
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Member Group: Members Posts: 164 Joined: 20-May 16 From: East TN Member No.: 20,019 Region Association: None |
Then you have power to the ECU. Somewhere between the harness plug and the 2 wire injector connectors is the discontinuity. The trigger points initiate the voltage pulse to the injectors. The ECU processes the several engine sensors to determine the pulse width. No power to the injectors at idle could be worn out trigger points, a bad ECU, disconnected injector grounds, bad harness wiring. Maybe more. I would check the trigger points as has been mentioned, use an ohmmeter. Pull the dizzy, or check it in the car while cranking. You are looking for alternating continuity between the center pole and each of the two outer poles as the diz is rotated. No continuity, no pulse, no voltage, noid light no worky. Not a big deal to take her out. I will pull it tomorrow and try this....Thanks again for all the help Jeff. Much appreciated. |
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