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| mepstein |
Aug 13 2017, 12:20 PM
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#1
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914-6 GT in waiting ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,218 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region
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I can't get my fuel pump to run unless I jumper the plug for the DME relay. The car starts and runs with the connection jumped but the fuel pump then runs all the time. Just want to know where to look and what to do.
I'm very electrically challenged so you might need to really dumb it down for me. Thanks |
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| Spoke |
Aug 19 2017, 09:27 PM
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#2
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Jerry ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,268 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None
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Mark and Ray stopped by my house today to do some debug on the fuel pump relay issue.
We made several steps forward and a couple of steps backwards. First when trying to see what works on the car, I put the turnsignal stalk to left turnsignals and it wouldn't go back to neutral. So every time we powered the car the left turnsignal was blinking. We traced a couple of wires on the 911 harness and realized the switched power to pin 86 of the fuel pump relay wasn't connected to switched power. Once connected, the fuel pump would run with ignition power. Success 1! Next the wire to the starter from the DME needed to be connected to the 914's yellow starter wire. After these 2 connections, the car started and ran as expected. When the engine was turned off, the fuel pump would also turn off. Success 2! The step backwards was realization that the ignition switch did not switch power off. Power on fuse #8 was always on. Once started, the engine could not be turned off until it stalled on its own, or the fuel pump relay was pulled or the battery cable removed. Things to do to finish the install: 1) Figure out why the ignition switch doesn't switch off power. 2) Connect yellow wire on the 911 harness (runs fuel pump when cranking) to the 914 yellow wire to the starter bendix. 3) Fix the turnsignal stalk so it doesn't stick on the left turnsignal. (IMG:style_emoticons/default/dry.gif) Question about the starter wire from ignition switch for those who know 911 engine transplants: Where is the best place to tap into the starter wire from the ignition switch? This is the smaller yellow wire that goes from the ignition switch to the original 914 relay board on pin 1 of the 14 pin connector, to the bendix on the starter. |
| timothy_nd28 |
Aug 22 2017, 09:12 AM
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#3
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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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Things to do to finish the install: 1) Figure out why the ignition switch doesn't switch off power. 2) Connect yellow wire on the 911 harness (runs fuel pump when cranking) to the 914 yellow wire to the starter bendix. 3) Fix the turnsignal stalk so it doesn't stick on the left turnsignal. (IMG:style_emoticons/default/dry.gif) Question about the starter wire from ignition switch for those who know 911 engine transplants: Where is the best place to tap into the starter wire from the ignition switch? This is the smaller yellow wire that goes from the ignition switch to the original 914 relay board on pin 1 of the 14 pin connector, to the bendix on the starter. You are correct, the start wire enters pin 1 of the 14 pin connector. Assuming the relay board is still being used in his setup, The start wire is again present at pin 6 of the 12 pin connector. You could also use either terminals II or IV on this relay board. This would be my first choice if you need this start signal from inside the engine bay. If you need to tie into the starter wire while inside the cabin, you can find a bundle of wires under the passenger seat. It is the same color wire from the ignition switch, it's pretty easy to differentiate from the other wires. Also, depending on the year of Mark's 914, you may want to bypass the seat interlock circuit under the seat as well. |
mepstein Need 3.2 conversion electrical help Aug 13 2017, 12:20 PM
Steve You did try another dme relay? Otherwise the Bent... Aug 13 2017, 01:06 PM
Spoke I had a similar problem on my 930. Engine would ru... Aug 13 2017, 01:21 PM
mepstein Tried 4 new relays. One was solid state.
Flummoxe... Aug 13 2017, 01:30 PM
Spoke
Tried 4 new relays. One was solid state.
Flummox... Aug 13 2017, 02:04 PM
porschetub The solder joints can also fail on them too,pop th... Aug 13 2017, 01:36 PM
mepstein
The solder joints can also fail on them too,pop t... Aug 13 2017, 01:45 PM
Spoke
I jumper the plug for the DME relay.
Which pins... Aug 13 2017, 02:11 PM
Spoke Some tests with your voltmeter:
put a small wire ... Aug 13 2017, 02:14 PM
Steve This manual is awesome!!
Aug 13 2017, 03:34 PM
Steve RE: Need 3.2 conversion electrical help Aug 13 2017, 03:36 PM
Steve RE: Need 3.2 conversion electrical help Aug 13 2017, 03:42 PM
jim912928 I hate wiring...do you have the red wire (fuel pum... Aug 13 2017, 06:38 PM
mepstein
I hate wiring...do you have the red wire (fuel pu... Aug 13 2017, 06:42 PM
Spoke Looks like a pretty simple circuit:
1) Ignition k... Aug 13 2017, 07:20 PM
mepstein I know the dme is good. Runs fine in other cars. Aug 13 2017, 08:30 PM
Steve Do what Spoke suggested and put an ohm Meter on pi... Aug 13 2017, 09:24 PM
mepstein
Do what Spoke suggested and put an ohm Meter on p... Aug 13 2017, 09:46 PM
shoguneagle Do not over look the DME Relay socket itself; shor... Aug 13 2017, 10:02 PM
McMark If you've tried the DME in other cars and they... Aug 14 2017, 07:02 AM
jim912928 The AFM point is a good one. Before I put my 3.2l ... Aug 16 2017, 05:30 PM
mepstein Huge step to have the engine start with the turn o... Aug 20 2017, 08:08 AM
Cairo94507 Glad to hear you resolved that issue and will be d... Aug 20 2017, 08:23 AM
jim912928 congrats! Aug 20 2017, 10:24 AM![]() ![]() |
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