I purchased a 85’ V12 motor for my 89’ XJS but it wouldn’t start once I put it in the car. The Lucas distributor’s High Tension Rotor was pointing the correct direction when at 1A ”0” as seen under the motor. On a whim, I rotated the cables on the distributor from the spark plugs 180 degrees and fired right up. However, it now surges high and low when it idle’s, but drives great. Very annoying and doubtful it will pass inspection. Any thoughts??
Look up AAV. Common to get stuck open, allowing too much air. When rpm at idle gets too high (cruising), ecu cuts fuel. Then when rpm drops, fuel back on. Bounces back and forth.
Best to rebuild the AAV.