fuel pump surging, why?? |
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fuel pump surging, why?? |
Tab914 |
Aug 1 2005, 06:52 PM
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#1
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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. |
mihai914 |
Aug 1 2005, 08:06 PM
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#2
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Senior Member Group: Members Posts: 800 Joined: 2-March 05 From: Montreal, QC Member No.: 3,697 Region Association: None |
To me it sounds like a fuel delivery problem. The fuel pump usually gets noisy when it's either pumping nothing like air or when it's pumping and there is a blockage in the fuel system.
Doesn't really matter what type of filter you put, as long as it's designed for FI and that you follow the flow direction of the filter usually indicated by an arrow or "in" and "out markings. Also check for any kinks in the fuel hoses. To check you pressure you don't have to buy and expensive automotive fuel gauge, you can go to your hardware store and buy a water pump pressure gauge along with a nice ribbed cone fitting that will allow you to slip a fuel hose over it. I would also clean the contacts on the relay board, change the fuse and swap relays. Usually if you have air in the fuel lines, the air is eventually pushed by the fuel flow. Was it really hot when this happened, it may be vapor lock if your pump is still in it's original location in the engine bay. |
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