 Fuel pump shorting out, help me find the short |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
| pgeorgeson |
 Nov 23 2011, 04:24 PM
Post
#1
|
|
Newbie  Group: Members Posts: 22 Joined: 23-October 11 From: Reno, NV Member No.: 13,710 Region Association: None  |
The good news: I got the fuel pump working.
The bad news: It keeps blowing the fuse. I am fairly certain that the pump not the problem. I think I have a short. I have checked the fuse panel and cleaned up all the contacts there. The main harness looks fine as it goes into the tunnel and comes out of the tunnel in the engine compartment. I have checked the wires coming off the main harness to the pump. The plug to the pump looks fine. From what I can see of it, the wires also look good behind the dash. I am thinking the short may be in the tunnel. Any specific ideas of where I should look for a short that I haven't looked for already? If it is the tunnel, is there any way to check for a short in there other than pulling the entire harness out? |
   |
 
|
  |
Replies
| ejm |
Nov 23 2011, 04:55 PM
Post
#2
|
|
I can see the light at the end of the tunnel Group: Members Posts: 2,717 Joined: 3-February 03 From: Massachusetts Member No.: 224 Region Association: None |
Assuming you are running stock fuel injection I would check the wiring to the auxiliary air regulator which is also powered by the fuel pump circuit. If the wiring looks good unplug the AAR and see if the short goes away.
A stock '74 would have the pump in the back and none of the associated wiring goes thru the tunnel. If the pump has been moved up front anything is possible. |
|
|
|
| pgeorgeson |
Nov 23 2011, 05:12 PM
Post
#3
|
|
Newbie Group: Members Posts: 22 Joined: 23-October 11 From: Reno, NV Member No.: 13,710 Region Association: None |
QUOTE(ejm @ Nov 23 2011, 03:55 PM)  Assuming you are running stock fuel injection I would check the wiring to the auxiliary air regulator which is also powered by the fuel pump circuit. If the wiring looks good unplug the AAR and see if the short goes away. A stock '74 would have the pump in the back and none of the associated wiring goes thru the tunnel. If the pump has been moved up front anything is possible. The pump is in it stock location in the right front of the engine compartment. Please excuse my ignorance (and be gentle with me). From what I can see, the wires for the pump are joined with the main harness that plugs into the front of the fuse panel (on the left side of the front of the engine compartment). That harness then runs down and along the bottom of the front left side of the engine compartment, then appears (although it is difficult to tell) to go into a hole in the bottom front middle of the engine compartment and into the tunnel. It appears, then, that the harness then also comes out of that same hole and then goes around to the other side (right side) of the engine compartment. I was assuming that because the fuel pump is switched to the ignition, then the fuel pump wiring ran from the fuse box, through the tunnel, up to the dash, to the ignition, and then back through the tunnel to the engine compartment and to the pump. Am i wrong? Does all the wiring for the fuel pump just run from the left side of the engine compartment (from the fuse box) across the bottom to the right side of the engine compartment (where the pump is)? (I would note that all the wiring that I can see in the engine compartment looks fine). In any event, I will check the Aux. Air Regulator. |
|
|
|
Posts in this topic
pgeorgeson Fuel pump shorting out Nov 23 2011, 04:24 PM
Cap'n Krusty You are, indeed, wrong. The pump wiring comes fro... Nov 23 2011, 05:48 PM
pgeorgeson
You are, indeed, wrong. The pump wiring comes fr... Nov 23 2011, 05:50 PM underthetire Doesn't the blower motor fan run off that fuse... Nov 23 2011, 07:12 PM vsg914 I agree with ejm. Aar cinnection is shorting again... Nov 23 2011, 07:28 PM pgeorgeson So the AAR was unplugged and the white wire was re... Nov 27 2011, 10:31 PM Dr Evil As someone mentioned, the blower motor also get po... Nov 27 2011, 10:40 PM pgeorgeson Blower (on front ride side of engine compartment) ... Nov 27 2011, 10:55 PM underthetire
Blower (on front ride side of engine compartment)... Nov 27 2011, 11:13 PM pgeorgeson I made sure the red lever was all the way down, bu... Nov 27 2011, 11:39 PM SUNAB914 Pull the heater knob control and clean the ground,... Nov 28 2011, 11:22 AM 914_teener
Pull the heater knob control and clean the ground... Nov 28 2011, 07:22 PM pgeorgeson
Pull the heater knob control and clean the ground... Dec 1 2011, 12:03 AM Dave_Darling The switch grounds the wire that goes to it. That... Dec 1 2011, 12:15 AM |
2 User(s) are reading this topic (2 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 17th April 2026 - 02:04 AM |
Invision Power Board
v9.1.4 © 2026 IPS, Inc.