Final tune, Need help |
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Final tune, Need help |
Morph914 |
Mar 23 2022, 12:34 PM
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#1
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Member Group: Members Posts: 435 Joined: 22-August 16 From: St Augustine, FL Member No.: 20,326 Region Association: South East States |
Ok , so I have the engine running but it needs tuning. A little background, rebuilt stock 2.0 with D Jet, running a 123 dizzy. It fires right up and idles a little rough at first then smooths out. It revs fairly well and sounds good. The problem starts under load, it starts to stutter a bit.
I have not messed with the adjustment screw on the ECU or tried adjusting the throttle position sensor, or been able to check my fuel pressure. I’m hoping to rally any troops in the north Florida area to help me get these final details ironed out. Thanks in advance, John |
Morph914 |
Apr 27 2022, 11:08 AM
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#2
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Member Group: Members Posts: 435 Joined: 22-August 16 From: St Augustine, FL Member No.: 20,326 Region Association: South East States |
Ok, so after locating the proper mps (037), and verifying that the fuel pressure is good (28-30)
I tried to start it but it would not fire. After adjusting the timing, It started up and then I fiddled with the timing a little more just by sound and feel. It is running much better now (IMG:style_emoticons/default/piratenanner.gif) Now the idle is up too high, around 1500 or so. I turned the idle screw in at the throttle body, but it seemed like it was in all the way with my fingers, so unable to get the idle down where it should be. Any thoughts on fixing the high idle? |
JamesM |
Apr 27 2022, 11:57 AM
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#3
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Senior Member Group: Members Posts: 1,915 Joined: 6-April 06 From: Kearns, UT Member No.: 5,834 Region Association: Intermountain Region |
I turned the idle screw in at the throttle body, but it seemed like it was in all the way with my fingers, so unable to get the idle down where it should be. Any thoughts on fixing the high idle? YES! Did you switch back to the proper timing map/vacuum retard on the dizzy? (and set your timing properly with a timing light) I wanst talking out of my (IMG:style_emoticons/default/bootyshake.gif) when i mentioned this earlier. Manifold vacuum at idle pulls timing which results in lower idle speeds. Beyond that, check to make sure the Aux air valve fully closes and that the crank case venting valve on the oil tower isnt letting to much air past. |
Morph914 |
Apr 28 2022, 05:32 AM
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#4
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Member Group: Members Posts: 435 Joined: 22-August 16 From: St Augustine, FL Member No.: 20,326 Region Association: South East States |
I turned the idle screw in at the throttle body, but it seemed like it was in all the way with my fingers, so unable to get the idle down where it should be. Any thoughts on fixing the high idle? YES! Did you switch back to the proper timing map/vacuum retard on the dizzy? (and set your timing properly with a timing light) I wanst talking out of my (IMG:style_emoticons/default/bootyshake.gif) when i mentioned this earlier. Manifold vacuum at idle pulls timing which results in lower idle speeds. Beyond that, check to make sure the Aux air valve fully closes and that the crank case venting valve on the oil tower isnt letting to much air past. How would I check the aux valve to see if it is closing? |
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