ignition problem PLEASE HELP!

[perna00]

My 96' 2.4 dohc engine wont start. i tested everything and found that the ignition module has a +12 volt output but is not sending a negative pulse to either of the coil packs to engage a spark. the only problem is that i already replaced the ignition module, both coil packs, coil pack housing, wires, plugs, cranksensor, and pcm/ecu. any help would be very appriciative. thank you.

[scrt79]

did you get yur pcm re-programmed?... maybe the eprom is pooched ???

[dave1627]

You might want to check into your antitheft system. Ever since my Cav was recalled for the ignition problem starting the car or even turning the key was very inconsistant. However the problem hasn't resurfaced for about a month it seemed to fix itself. The problem was rooted in the anti theft system for the ignition. Just a thought.

[perna00]

the pcm was reprogrammed by the company that made it. they took all the information and the vin. suprisingly the pcm/ecu was only $119 programmed and everything at autozone. as for the antiftheft system, the light is not blinking on the dash with the key on that shows that it is disabling the ignition. any more suggestions?

[scrt79]

check your pass-lock sensor, sometimes they just start failing every now and then, or your ign. switch itself.... or just get someone to run the codes.. that normally shows about EVERYTHING there is to know...

[perna00]

everything is getting power. even the ignition module is putting out +12volts to the coil packs. the problem is that the ignition molule is not sending the negative pulse to the coils making them send voltage to the plugs

[scrt79]

hmmm....have you gotten any codes off of the vehicle?

[scrt79]

Crankshaft position (CKP) sensor activity (7X reference)--The CKP sensor generates a signal to the ICM which results in a reference pulse, square wave signal, being sent to the PCM. The PCM uses this signal to calculate crankshaft position, engine speed and injector pulse width. The engine will not start or run if this circuit is open or grounded.
Reference Low-- his wire is grounded through the ICM and insures that the ground circuit has no voltage drop between the ICM and the PCM which could affect performance. The PCM compares voltage pulses on the 7X or reference input to those on this circuit, ignoring any pulses that appear on both. A pulse that appears on the reference low circuit alone is assumed to be caused by radio frequency interference (RFI).
Ignition control (IC) 1 & 2--The PCM sends the ignition control pulse to the ICM on these circuits. These signals are similar to the 7X reference pulse square wave except that the PCM uses sensor inputs to determine the pulse timing to control spark advance. When the PCM receives the 7X signal, it will determine which pair of cylinders will be fired (1 & 4 or 2 & 3). It then tells the ICM which cylinder to fire through the ignition control circuits.

[perna00]

nope, no codes. that latest info should help. i'm going to try testing all the wires now. i'll reply and let you know

[perna00]

can anyone tell me if the ohms should vary between 750-850 for the crank sensors reading?

[scrt79]

The CKP sensor should output a voltage near 1100-1300 mV as the crankshaft turns. It is possible to trigger the ICM with a voltage as low as 200 mV. If no voltage is produced, a poor sensor connection or faulty sensor is indicated.

[scrt79]

ckp = cranksensor