Technical Support - Electronic Systems - EFI Troubleshooting
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Popping out of ram tubes

• Popping out of the ram tubes is an indication of two possible concerns. Either the butterflies need to be adjusted or the tip-in air fuel ratio is lean. A combination of both is possible.

• If the popping occurs at idle and can be traced to the same cylinder, then adjustment to the butterfly of the affected cylinder will be required. If you already have a copy of "Injector Manifold Adjustments", please follow the technique described. If a copy of these instructions or assistance is required please contact us.

• LOW RPM-Idle to 3500 rpm: If popping occurs during throttle tip-in at low rpm, then adjustments to the FC and MC at 1000 will be required. This condition is an indication of being lean and therefore you will turn the adjustment pot to a higher number. It is important to note that only small adjustments are necessary. If, after making adjustments, the problem still persists or you are now running too rich with possible smoking, you will then need to perform adjustments as outlined in "Injector Manifold Adjustments" page. Also, please see "Tuning By Percentage Of Throttle Opening" page of the Tuning Manual for definitions of the FC and MC circuits.

• HIGH RPM-4000 rpm and up: If popping occurs during throttle tip-in at high rpm, then adjustments to the FC and MC at 8000 will be required. This condition is an indication of being lean and therefore you will turn the adjustment pot to a higher number. It is important to note that only small adjustments are necessary. If, after making adjustments, the problem still persists or you are now running too rich with possible smoking, you will then need to perform adjustments as outlined in ”Injector Manifold Adjustments" page. Also, please see "Tuning By Percentage Of Throttle Opening" page of the Tuning Manual for definitions of the FC and MC circuits.

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