savanna.seven

iTrader: (5)

The car is an S4 TII with a rebuilt stock motor. I'm getting hesitation/studdering under throttle but that is an issue for my other thread. While doing tests for that I came across the fact my trailing 1 plug is not firing.
I'm getting spark on all other plugs except T1. I've swapped wires to make sure it wasn't them and also swapped ignitors with a known working one and I'm still getting the same issue.

I searched around the forums and found some useful info but everyone else seems to be having issues with either the whole assembly isn't sparking or T2 isn't sparking + no tach.

On the coil assembly there's one 4 pin connector and one 2 pin. I tested the 2 pin and both black/yellow wires are making power. I then tested the other 4 and none made the test light go off. From what I understand one is the IGN-select whic determines what coil to fire and the others are IGN-confirmation and IGN-F.

None of them show power. Am I testing wrong or is they're maybe a bad signal at the ECU? Sorry for the long story. Just trying to understand what's going on and why its acting this way

satch

iTrader: (1)

Do you have a multimeter for you need one as the test light isn't going to be of much help. Blue/Red wire should be below 2 volts w/key to on and about 1.3 volts at idle. Brown/Yellow should be 4.4 volts w/key to on and 2.2 volts at idle. With the key to on and the engine turned over by hand using the alternator pulley to rotate the engine this Br/Y wire should alternate from 0 volts to 5 volts back and forth. Blue/Yellow wire should be 0 volts w/key to on and close to 1 volt while idling. The Yellow/Blue wire feeds the tach and if the tach is working properly then this wire should be okay.

savanna.seven

iTrader: (5)

Ok did some testing and some of my readings are way off conpared to what you listed.

Blue/Red
On - 11.93v
Idle - 13.30v

Brown/Yellow
On - 4.99
Idle - 2.57. These were close
[Spinning it by hand did nothing to the readings]

Blue/yellow
On - 0.01v
Idle - 0.01v. No changes.

So what can I learn from this info???

satch

iTrader: (1)

Make sure the coil is bolted to the fender properly as this is how the coil/igniter receives its ground. If the coil/igniter is not grounded you would get a voltage reading of about 12 volts on the Blue/Red wire so sand down the fender if need be to make sure the contact between the coil and fender is good.

savanna.seven

iTrader: (5)

Okk. I sanded down my contacts haha so there's no questioning.

My readings did change some tho :]

Blue/Red
0.98
1.3 Better

Brown/Yellow
4.29
2.2. On spot
Turning over by hand and socket didn't change from 0 to 5 at all.

Blue/Yellow
0.04
0.81

Still no spark at all from T1 coil.

satch

iTrader: (1)

How are you testing for spark on T1? The best way to do it is to remove the T1 plug from the trailing coil and place it closely against the coil bore leaving just a fraction of an inch between the plug and bore and start the car and see if there is any evidence of spark. Also go to the ECU and take a reading on pin 1U (Brown/Yellow wire) and take the voltage reading as someone assists you in helping to turn the engine over by hand w/the key to on and see if you get the same reading taken earlier at the coil. When the engine is turned over by hand the reading will mostly stay at 0 volts then only briefly jump to 5 volts before reverting back to 0 volts once again. Lastly, when spun by hand w/key to on what does the Br/Y wire read?

savanna.seven

iTrader: (5)

We used a flathead infront of the coil bore and nothing, tried arcing the spark plug and nothin, used the timing light to see if it would flash I know that's not accurate ut also swaped plug wires from t1 to t2 and back and still nothing.

The brown/yellow read 4.29v with ign on. And 2.2 with it idling. It didn't fluctuate from 0 to 5 at all turning it by hand.

I will try the ecu tomorrow. what do you think would cause the t1 to stop sparking?

satch

iTrader: (1)

Seems like you might have an issue w/the ECU. Perhaps HAILERS will chime in and give his two Yen. I would also suggest checking for spark as I mentioned just to clean up any possible loose ends.

EDIT:
And your problem might be a plug problem so check for spark like I suggested to rule that out. If you swapped plug wires w/the plug then forget about it being the plug.

savanna.seven

iTrader: (5)

Ok. That's what I was worried about. I just don't understand how it ran perfect. Swap motors with the one that was rebuilt and now its acting up.

I will deff check the ecu pin you suggested and double check the plug. I'm almost 100000% sure its not the plug but like you said its best to eliminate all loose ends

HAILERS2

http://rx7.pw.cx/guides_manuals/coll...ystifying.html

Read the above article from FC3S forum written ages ago. Then look at the attached jpg that comes from that article.

From the jpg you can see that if the SELECT signal is going from 0-5 vdc during the rotation of the *crank*shaft, then both trail coils should be firing.

We assume that the number two trail coil is working 'cause you'd have said so if it were not working. Right? Right. Plus you tach would not be working either if both trail coils were not firing.

So pull apart the trail coil assy elect plug and do the following:

So you get your meter out and put your meters lead on the select signal wire in the Trail plug and put it on dcvolts and rotate the front pulley by hand with key to ON. You should see the meter go from zero to five volts as the pulley is turned.

The wire color is shown in the attached jpg called READTHISTHREE

IF you see the select signal going from zero to five volts or five volts to zero (your choice of how you look at things), then the CAS and ECU are good and the problem is with the ignitor in the trail coil assy OR the coil in that assy that is not working. Like the man said, the trail coil has to be bolted down to the frame with at least one fastener 'cause the guts of the trail ignitor gets its gnd from that contact. Same with the lead coil assy as far as being bolted to the frame with at least one fasterner.

JUST IN CASE: Don't get confused after reading the article. When you do the test I described, all your doing is looking for the meter to got from zero to five volts time after time as you rotate the front pulley. You are NOT looking for spark or any other thing at this time in life.

savanna.seven

iTrader: (5)

You guys are awesome. I really appreciate the help. I will check everything out after I get off work. If I run into issues ill go over a second time before I post results. Thanks for all the help!

hatemy7

Just change your coils!!! Trailing and leading! Same thing happend to me!

savanna.seven

iTrader: (5)

I've swapped coils 3 times. Even tried my friends from his running fc

HAILERS2

Did you change out the coil for the non working trail coil or did you change out the whole Trail coil assy which includes the ignitor?

Does your tach work or not?

savanna.seven

iTrader: (5)

I swapped the entire assembly 3 times. And yes my tach works awesomely.

satch

iTrader: (1)

Have you checked for spark for T1 at the coil bore yet?

savanna.seven

iTrader: (5)

Yessir. Checked on my lunch today again.I thought I heard it arc bui guess I was wrong. Let it run for 5 min waiting for any sign of spark and still nothing.

HAILERS2

Does T2 work or not?

satch

iTrader: (1)

To surmize,

He states that T1 is the only one which doesn't spark. He also has the proper voltage on the Br/Y wire w/key to on and while at idle when the readings are compared to those provided in the FSM, but the select signal wire (Br/Y) "does not" do the 0 to 5 volt pattern. He also states he has tried different coils from a known working car and the net result is the same. Wonder if the CAS could be a problem or if it is the ECU?

HAILERS2

Just off the cuff and in a hurry.....................the select signal has to be doing the 0-5vdc routine if the T2 is firing. I don't see anyway around that being the case.

satch

iTrader: (1)

What if the voltage was stuck on one of the two voltages which fires just T2? Possible/not possible.

HAILERS2

IF the voltage from the ECU stayed at either zero or stayed at five.........the sparkplug would fire maybe one time after the key was put to on and never again.

I took fifteen minutes out of my lazy day time and did this on one of my cars. The voltage stayed at five volts for what must have been the better part of a full turn, then instantly turned to .22vdc and stayed there for the better part of another turn and then became five volts and on and on and on and on the same routine.

I even turned the front pulley by hand in the wrong (ccw) direction when doing this. No need for a socket etc. Just grab that sucker with your left hand and turn in either direction. Fan blades are bothersome though scrapping against your hand.

After putting all plugs back on I pulled number one sparkplug wire out of the coil bore and layed it just at the bores front. Key on and turned the pulley by hand. After a better part of a turn of the pulley ...........SNAP! goes the spark b/t sparkplug wire and coil bore. All's well.

So if you don't get the rise and fall from zero to five vdc..........and you changed coil assy several times......swap ECU with your buddys car.

savanna.seven

iTrader: (5)

Alright. I feel like I'm getting nowhere lol. This cars soo much trouble. I drove it around again. Bogs and jerks on slight throttle and low rpms. But smooth if you get on it at above 2500. I'm gonna go over all my grounds after testing the voltage from the wiring like you said. I don't have a spare turbo ecu so ill post results when I can get a hold of another

satch

iTrader: (1)

One thing you could do is just disconnect the trailing coil as the engine just needs the leading coil to run and see if the car behaves differently. Most of the fuel injected into the rotor housing is ignited by the leading coil and any left over is ignited by the trailing coil so the trailing coils job is basically there for emission purposes.

savanna.seven

iTrader: (5)

:/ car still bogs/jerks with trailing unplugged under 3k.
Also if you are barely on the trottle it still makes a stuttering sound like it stuck. Ill post a video tonight