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 2 2005, 11:04 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 |
Yeah! Learning alot about my patience.......... (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)
I found out from Gordon Luy that the heads are interchangeable though. Me thinks that someone took the engine apart for a rebuild or what not and when putting it back together switched the heads by mistake and only realised after most of it was put back together. I guess it was easier to punch a hole in the cooling tin and swap sides for the HTS then to tear down again and reswap the heads. Gord tells me that this in no way affects the HTS. I did swap the sensor today and got better results. Brought the car up in temp to the usual spot and no surging. (wasn't as warm out today though) Did get some stumbling from the engine though. I didn't drive the car today and only brought up the temp from idling and steady revs of the engine. I got some engine poping and gurgling (burping, missing, whatever) at low rpms (1200-2000) on steady revs and acceleration. It seemed fine at steady higher revs (2500-4000) Does that mean running a little rich or a bit lean?? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) Still plan on doing the fuel pressure test hopefully tomorow if not then the day after. Will also change fuel lines, filter and check screen in bottom of tank. Also fuel line to fuel pump and injectors. Will let you know of the fuel pressure and hopefully get more of your input. Thanks again. (IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif) |
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