fuel pump surging, why?? |
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fuel pump surging, why?? |
Tab914 |
Aug 1 2005, 06:52 PM
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#21
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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 1 2005, 10:36 PM
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#22
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Member Group: Members Posts: 158 Joined: 25-April 04 From: Alexandria, Ontario, Canada Member No.: 1,978 Region Association: Canada |
Thanks Dr. Evil.
I will perform a fuel pressure test hopefully tomorow. I need to get pressure guage first. As soon as I have results I will post them. The PO had put in a new fuel pump and I am trying to find it in my papperwork to see if it was the proper one as I don't have the car jacked up at the moment. The TPS is brand new from 2 weeks from PP and it was installed as per the tech article on PP. I was suspecting the HTS but the ohms seem right on it. Fuel delivery has become my main focuss and hopefully a pressure test will tell us more. If the fuel pump is not the exact right one, would the engine run anyway?? Thing is this only starts happening when warmed up. I don't have a spare ECU for 2.0 lt but do have one for 1.7lt. Any possibility of it working enough just to check?? Could I be getting vapor lock from the fuel lines in the engine bay?? Tried to take it for somewhat of a spin just to see how it would react today after warm up and it just coughed real bad under load as usual. Feels like the fuel is not getting there. What do you think? (IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif) thanks again Dr Evil. |
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