kborro01

iTrader: (3)

Okay I tried to be as complete in my description as I could. I'm hoping someone can confirm my diagnosis before I start ripping things apart to get to the ECU.

When Starting cold, the tach works and everything is fine. After 5 to 10 seconds, the tach goes to zero and I start getting a code 01 which indicates trailing coil. I shut off the card and let it sit over night and start the following tests:

-Checked to see if the plugs were actually firing - they were not
-Checked to ensure the coil body was grounded - it was
-Checked coil resistance - below 1 ohm as specified FSM page G27
-The 2 pin coil pack connector - constant 12 volts with key on
-Blue Yellow wire - cycles the between 0 and 5 volts as pulley is turned
-Blue Green wire - constant 5 volts
-Brown Yellow wire - Cycles between 0 and 5 volts as pulley is turned

I start the car and after 7 seconds the tach goes to zero and with the engine running
I do the following tests
-On the 2 pin connector both wires have constant 12 volts
-brown and yellow wire - the test light flashes(Ground signal from ECU)
-Blue Yellow wire - No test light flashes
-Blue Green wire - Constant test light
-no spark at either plug wire

I shut off the car and do the following test
-Two pin connector - 12volts constant with key turned on
-Blue green wire - Constant 5 volts
-Blue Yellow - cycles between 0 and 5 volts as the pulley is turned
-Brown Yellow - immediately after shut down constant 5 volts , after 15 minutes cooling off it then cycles between 0 and 5 volts as pulley is turned

Tried two other coil packs with the same results. The only difference I noted between the results is the cooldown and the signal on the brown and yellow wire.

I' leaning towards the ECU, but I'm not really sure what part the CAS plays, It would seem it should be working because the coil pack is getting the cycling of the ground signal which tells it to fire. I ran what tests I could think of as I have no way of actually seeing if the coils are charging and discharging, I would think that trying different coil packs would take care of that.

Any ideas before I start pulling out stuff to get to the ECU?
Thanks

satch

iTrader: (1)

How are you checking for spark. The best way is to take the plugs/wires out of the equation. Pull the plug wires from the coil bore and place the plug wire boots within a fraction of the coil bore and w/key to start check for spark. You could also test the wires according to spec in the FSM. And you could also use the leading coil plugs and wires and use them on the trailing coil to see if there is a difference. And how did you verify the grounding of the coil other than visually? Did you remove the coil and sand down the contact points in addition to cleaning out the bolt threads of dirt?

kborro01

iTrader: (3)

I tested the wires by swapping them with the leading coil and they functioned fine. Testing for spark was done the old fashioned way of checking for an arc between the plug wire and ground. This method displayed a spark on the forward, but not the trailing.
the body of the coil reads .02 ohms of resistance between the coil body and the negative terminal of the battery. So definitely a good ground. Same resistance results with a second coil pack I installed.

satch

iTrader: (1)

Then that leaves the trailing plugs as a possibility.