fuel pump surging, why?? |
|
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 surging, why?? |
Tab914 |
Aug 1 2005, 06:52 PM
Post
#1
|
Member Group: Members Posts: 158 Joined: 25-April 04 From: Alexandria, Ontario, Canada Member No.: 1,978 Region Association: Canada |
Another one for you guys...........
Here is the problem I am trying to fix. Whenever the needle in the temp guage gets to about 1/4 the fuel pump starts surging. This causes the idle to start to go up and down in rythm with the fuel pump. Also when under load the car stutters and shudders and kinda wants to choke. Before the car gets up to that temp. it runs nice and smooth, strong on acceleration and no poping or backfiring on decel or anything. Just sounds great and runs fine. Idle is where it should be and fuel pump does not surge. Here is what has been done. -Valve adjustement -Dwell adjustement -Timing adjustement -Tested MPC as per proper ohms. Parts I have changed- coil, plugs, ignition points, trigger points, condenser, rotor, cap and wires. Questions:- what could make the pump surge like that? -does it make a difference how the MPC wire goes into it's conector? -How do I properly check the head temp sensor. -Could the intake temp. sensor be the cause. I am at a lost. Feel like I am going in circles. (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) Has anyone had this kind of problem?? Desperate for advice. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) Thanks, Dominic. forgot to add. car is a 1974 2.0 with stock fuel injection. |
Tab914 |
Aug 1 2005, 07:33 PM
Post
#2
|
Member Group: Members Posts: 158 Joined: 25-April 04 From: Alexandria, Ontario, Canada Member No.: 1,978 Region Association: Canada |
Thanks guys! Ya I meant MPS. (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)
Mihai! What I mean by the fuel pump surging is that I can hear it change sound. It kinda whirrrrllllss and then nothing and then whrillllss again and so on. Dave! I will try cranking down on the knob on the ecu and see what happens then. As for a vacuum leak, I have all new hose installed but I guess that is still possible. I don't have a pressure guage. I remember putting on a new fuel filter but only one that looked liked the previous one and never by actual product #. That bad?? Also in the engine bay are plastic fuel lines (which I know I should change and will) and in the lines I can actually see air gaps when the fuel is just sitting there (engine off) and it never seems to be full solid of fuel when running. (air bubbles) This is probably a stupid question but....... is that bad?? How do I fix. I'm guessing I would need to drain all the fuel but then how do I get the air out of the lines. Thanks again. |
Lo-Fi Version | Time is now: 6th June 2024 - 02:33 PM |
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 ... |