08 crown vic tach wire

The wiring guides I have found say to use "not red or RED / green, any ignition coil or injector" for my 08 Crown Vic. Following those instructions, when the car was remote started, the started stayed engaged after the engine was running, until the engine was killed by pressing the remote start button again. I probed several wires at the PCM for AC voltage and even tried a couple of them by making a temporary connection to the tach signal wire going to the alarm. All produced the same results as above. I installed a 454T tach signal generator but it really didn't work that well. And only made a good tach signal if the car was already warmed up. I removed the 454T and am now back to looking for wires to probe. The car has a distributorless ignition system. Is there any particular wire that can be used or do you have to use the 454T and just tweek with it until you get it right?

There should be a Pink/White wire in the PCM above the driver's side shock tower. The wire is in the connector closest to the driver's side fender. If you check it with a digital volt meter set to A/C voltage, you should see around 0.5 volts and it will increase with RPM. Also check that you have the ignition, accessory and starter wires connected correctly. Some of those cars have 2 ignition wires and 2 accessory wires.sparky

I did probe that wire. Actually two wires to be correct. I probed both white / pink and pink white for AC voltage. Neither read anything and taking a chance I also connect the tach signal wire to both to see what happened. The alarm is set to tach (not virtual tach) and it just kept cranking (started engaged) even though the engine had already started. I read somewhere else that a black pink wire was at the PCM and could be used for Tach, so I probed that as well. I also probed a black / purple wire just in case my eyes were tricking me as to which wire was actually had a "pink" stripe. The colors are all somewhat faded and dirty. The black / purple wire had AC voltage and the car remote starts perfect using that wire. I "learned" the alarm to that tach signal and all seems to be functioning correctly now.