Well, today was the day that I was suppose to start the car finally after building it for the last year. Go to start it up and it just turns over. I know I am getting fuel(I checked) plus I have been sorted 3 fuel leak issues over the last month. Well, I go to check spark and the rear rotor's trailing plug(top one) is not getting spark. I got out my spark tester and started at the plug to plug wire connection and got nothing. I then tested the plug wire to coil pack and got nothing. Mind you, I test all three other plug and wire and coil connections and got spark no problem. I put the test light on the connector and it working fine. Well, I had an extra Trailing 2(the one closest to the firewall) coil so I changed it out and I am still having the same issue. Can anyone think of any thing else it could be other than a bad coil? How can I check the coil itself? Finally, would one coil being bad cause the car not to start? Thanks guys.

Brent

 

The car will definitely still start if one trailing coil isnt working.

Are you sure you have the wiring harness plugged in properly? I'd check everything thoroughly, something doesnt sound right. Motor might be flooded.

P.S. The FSM has the procedure for testing the resistance across the coils.

 

+1.

I had a similar problem recently, but I was getting spark at all of them. Turned out that it flooded during all the testing.

 

Yes, I'm sure it isn't flooded and I have checked, rechecked, and checked again to ensure I have the proper connectors and plug wires plugged into the coils and spark plugs. I originally pulled the spark plugs to see if it was flooded and they were dry. What else guys?

 

Hm, are you sure you don't have the fuel feed and return line mixed up? I know you said you checked, but it's a pretty common mistake.

 

Also check the wiring connector to the coils I had a similar prob and it turned out the wire had come loose from the connector. Have you checked the plugs on the coil are all on properly? Checked the ignitor?

 

Return is closest to the firewall, middle is ventilation that goes to catch can under elbow, and feed is on the other side of ventilation... right? I thought that was right but I may be wrong. I'll check those again tomorrow.

 

Already checked the wiring connector with a test light. It is fine. All plugs are on properly. If the ignitor was bad, wouldn't that mean the other 3 coils wouldn't fire?

BTW, thanks for all the suggestions so far. I'm def. going to look up in the FSM how to ohm test the coil pack tonight.

Also, after it didn't fire, I took the PFC out and replaced it with another PFC out of a running FD just in case it might be a bad PFC... no dice.

 

I should have two stock trailing coils ,do you need one ,,, How to check ,do this unplug both trailing coil connectors and swap the coils . If the same coil does not fire then it is the coil ,, if the fail is still on the same connector then you know it is not the coil . Motorcycle trick from my younger days.

 

Haha... thats the same thing my dad said when I called and asked him... which he learned back in his motorcycle days too. I tried it on 3 different coils on the bad one and didn't have any luck. I know the T1 coil that is currently installed is working though... I guess I will try swapping it since I know that one is good. Like you said, that can tell me for sure if it is the coil or something else.

David, if it turns out that I have 3 bad T2 coils, I may be giving you a call tomorrow. Thanks.

 

I will be here in the afternoon . If you have three bad ones that would be hard to believe .

 

Ok, here is what I've got. Verified I have a working coil by plugging the connection into the front rotor trailing coil connector and put a spark tester on the coil to plug wire connection. So I have verified that it is not the coil. Now, the connector plugs. The top one is a constant power source and I have verified with a test light that the top wire of the connector is working. However, what does the bottom wire do? I know on some ignition systems, it would be a ground that would tell it when to fire. However, I have not been able to get a reading on any of the bottom wire of the connectors with a test light, either as a hot wire or a ground, but the 3 other spark plugs are getting a spark. I'm about to start searching now to find out what the bottom wire of the connectors do, but if any of you can tell me before I find it, I would greatly appreciate it. BTW, it is the green wire with a silverish white strip down it on the blue connector that plugs into the trailing going for the rear rotor. Thanks guys.

Brent

PS, if anyone needs me I'll be elbows deep in the FSM

EDIT: Ok, so they are a ground. How can I test these. I would of thought I could put my test light on a hot wire and touch it to a ground and it would light up, but I have not had any luck. I have tried cranking the car while doing this as well with no luck... on any of the connectors bottom wire.

 

Brent,

According to page Z-28 in the wiring diagram, the Light Green / White wire should be grounded to charge the coil.

However, according to page G-8 of the Service Highlights manual, each coil driver has a resistor between the coil and ground. This might explain why your test light isn't identifying it as ground.


By the way, the coil charge time is less than 5 ms (0.005 seconds) at idle, which is practically impossible to catch with your eye. For comparison, movies and broadcast TV display about 30 frames per second, which is 0.033 seconds per frame.


Your time might be better spent using your multimeter to verify that you've got connectivity between the ECU >> ignitor, and the ignitor >> coils. Have you got a known-good ignitor that you could try swapping in?

 

I should have one laying around here somewhere, but if the ignitor was bad, would it still be firing the other 3 coils?

 

This doesn't really help solve your problem, but be aware that there are only three coils -- one for each trailing plug, and a single coil shared by both leading plugs.

Just to check that it isn't a bad plug wire or spark plug, have you tried plugging the wire+plug that doesn't fire into the other trailing coil? Or plugged one wire+plug that does fire into the "bad" coil?

-Max

 

Yeah, I know how many coils there are I have already verified all of that and have narrowed it down to the connector as mentioned above.

 

Yes, I'm pretty sure you could zap one channel without hurting the others. The ignitor is basically a few high-wattage transistors mounted in a heatsink.