Still chasing a surge or a miss on L-jet 2056 |
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Still chasing a surge or a miss on L-jet 2056 |
jmargush |
Jul 30 2014, 07:51 PM
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#1
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Member Group: Members Posts: 458 Joined: 8-June 04 From: Goshen, IN Member No.: 2,176 |
Still working getting the 2056 L-jet to run well.
I have a surge or miss under hard acceleration 3500rpm and above. It doesn't happen every time and I think it is more likely to happen under rapid wide open throttle, but I can get good acceleration pulls sometimes. If it does start to surge and I stay in it I stay on the throttle I can hear a pfft or burp of air which I think is coming out of the exhaust. Fuel pressure (with Harbor Freight gauge) is reading 39psi under hard acceleration Timing is set to 28 dgrees BTDC@3500 rpm New plug wires and plugs Cleaned distributor and regreased (running Pertronix) Tried 2 different Bosch coils with same results Could the fuel pump volume be out of spec and still deliver pressures like I am seeing?(what are the specs for fuel pump volume test?) Should I try a different timing setting, more or less advance? Could the potentiometer in the AFM be hitting a dead spot? Or could a bad plug wire give intermittent issues like this? Starting to get old car-ed out! |
Java2570 |
Jul 31 2014, 02:26 PM
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#2
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Senior Member Group: Members Posts: 649 Joined: 7-May 11 From: Fishers, IN Member No.: 13,035 Region Association: Upper MidWest |
I can't remember, do you have an air/fuel meter hooked up in your car? If so, do you see any fluctuation in mixture at this point? I just installed all new fuel lines and fuel pump and I have a kink in one of my rubber hoses under the tank (I believe).....I have a very obvious fuel starvation at load. My AFR meter just takes a dive when this happens and is a good indicator of whether you have a fuel delivery problem.
Of course, your issue could still be related to your L Jet AFM or ? I've got D Jet so I've no experience with your setup but an air/fuel meter is good info to have at your disposal! Jon |
jim_hoyland |
Jul 31 2014, 02:46 PM
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#3
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Get that VIN ? Group: Members Posts: 9,270 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
If you are still using the L-Jet dual relay, be sure it is secured and not bouncing around. Second, double check the wire from the dual relay to the fuel pump. I has to be in there tight- it might be vibrating a tiny bit and interrupting the circuit.
You can bypass the dual relays fuel pump circuit by grounding III on the relay board, that would be the 4 spade connector in the rear left corner. |
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