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. |
Tab914 |
Aug 6 2005, 10:02 PM
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#2
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Member Group: Members Posts: 158 Joined: 25-April 04 From: Alexandria, Ontario, Canada Member No.: 1,978 Region Association: Canada |
[/QUOTE]High fuel pressure will mask very well other problems especially vacuum leaks. (tried to do the quote thing here but don't know how)
That's what I thought when I noticed the difference in how the car ran. The fuel pressure might have been set high to compensate. As for the MPS it's not that it leaks it's that I can't draw a vacuum at all. I tried with a pressure pump and guage and nothing. Took the pump off and tried sucking on the hose and nothing. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) Couldn't get any suction on my tongue. Tested the guage and pump another way and it works. So me thinks it's screwed. Probably still good to knock someone out if I threw it and hit him in the head with it. (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) Now the hunt for a replacement is on. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) |
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