Fuel Pump Diagnostics |
|
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. |
|
Fuel Pump Diagnostics |
solex |
Mar 21 2010, 12:40 PM
Post
#1
|
Senior Member Group: Members Posts: 789 Joined: 12-January 05 From: Long Island, NY Member No.: 3,439 Region Association: North East States |
Hi All,
Need a little help to diagnose a fuel pump problem in a 75, I do not hear the pump when I turn the key to the run position. The car was running, I had a few occasions where it would not start, let it sit for a few days and it was start right up. The grounds: under the relay board, battery and transmission have all been cleaned. All fuses are good. The relay is working as I can hear it click into position. When the key is in the run position relay terminals 30 and 85 shows 12 volts. Terminal 86 show 0.03 volts and terminal 87 show zero volts. There is no voltage at either of the fuel pump terminals. The readings at the relay is counter to to what Haynes states (86 should read 12 and 85 should be ground). I not sure where to check next, really do not want to pull the tank. Any assistance would be appreciated. Thanks, Dan |
swl |
May 2 2010, 09:10 AM
Post
#2
|
Senior Member Group: Members Posts: 1,409 Joined: 7-August 05 From: Kingston,On,Canada Member No.: 4,550 Region Association: Canada |
I'm all for being methodical in trouble shooting but you know I'm beginning to think that "check the relays" should be the first step in any diagnostic process. Followed by "check the fuse" and then go to Brad's tools. Relay failure is just so common that the 5 minutes (less if you don't have to steal the relays from the headlights) it takes to check the relays is time well spent.
BTW you can take the can off the relay and expose the actual solenoid. You might be able to see the point of failure and maybe resolder the bad connection. It is the CSOB thing to do (IMG:style_emoticons/default/smile.gif) |
Lo-Fi Version | Time is now: 2nd June 2024 - 03:26 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |