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-   -   All I Want Is A Spark! (https://www.nopistons.com/2nd-generation-specific-17/all-i-want-spark-36541/)

annuerysm 03-31-2004 03:42 PM

I have a 88 SE and Im in the middle of reinstalling a motor I rebuilt. As stated above I can get the spark plugs to fire. I have replaced the coils from a parts car (87 GXL) I have and I have seen those coils make a spark before so Im fairly sure the Coils/Ignitors are ok. Im starting to suspect the ECU but when the one from my parts car is a different model (N326) instead of N327 so I'm not sure if I can test it just by swaping them. However, I took the ECU out and looked at the PCB and it seem to be in good shape none of the electrical components seemed damaged and I seemed to have a good voltage at the pressure sensor of pin A2 (above 4.5 volts). If it isnt the ECU what else could it be? is there a fuse or something that I am missing? and helpful insights would be much appreciated. Thanks.

-Dan

Cosmo Donk 03-31-2004 04:31 PM

I think you meant "can't" instead of "can" in the body of the text.



Check for power at the coils. If there is power place the plugs by a ground, a bolt or something, and have a buddy crank the car. You should see sparks. Don't worry about it if the trailing don't fire for now. If you are still not getting spark from the coils make sure all fuses are good and then there is a way to check the coils if they are good but it involves splicing the trigger wire to the coils and touching it to ground with the power on.

1Revvin7 03-31-2004 07:30 PM

Check for power at the coils 1st as mentioned.

annuerysm 03-31-2004 10:38 PM

I have voltage at both the leading and trailing coils I just checked. I dont think the ignitors are getting a signal? what is the best way to check this?

Cosmo Donk 04-01-2004 08:56 AM

Well, there is a way described in the FSM but you need a special tool. The way I know of involves splicing the trigger wire, the wire next to the power wire (pink or tan, I forgot). It is the one we use to hook up the Haltech. If you were to cut that in half you could then quickly and shortly ground that wire with power to the coil and it will spark.

annuerysm 04-01-2004 09:27 AM

Thanks Cosmo Donk for that trick Im going to try that, but I'm going to disconnect that wire from the coil at the little nut instead of cutting the wire, and run another wire to the ground to test it, is there anything wrong with this logic or do I have to splice it? Also does anyone know what the difference is between the N326 and N327 ECUs?

Cosmo Donk 04-01-2004 10:14 AM

Nothing wrong with that logic, although I don't know the nut you speak of. Just as long as the trigger wire goes directly to ground and you do it quickly.



Dunno about the ECU's.



Hope it works and please post your results.

1Revvin7 04-01-2004 10:18 AM

Now you have to check if the CAS is within spec. The fsm lists the resistances it should be within. Then you have to test if the cas is sending its signal to the ecu and if the ecu is getting it.

annuerysm 04-01-2004 01:05 PM

I tried Cosmo Donk's ignitor testing trick by cutting the Pink wire on both of the leading coils I own. I briefly touched the now exposed ignitor wire to a ground wire that was attached to the negative battery post. the coil had power when I did this test and I tried to ground out the spark plugs on just about everyplace I could thing of in engine bay. Still no spark! Is this test conclusive that both my leading coil/ignitors are FUBAR? because I know that the leading coil from my parts car was able to make a spark. Could something else be causing the ignitors not to fire? or what could be killing my ignitors?



I checked the CAS and the resistance is within spec.



also what is the best way to check if the CAS is sending signal to the ECU? can I just check continuity?



BTW Thanks a lot for the help Cosmo Donk and 1Revvin7

rx7_re 04-01-2004 01:26 PM

1 Attachment(s)
yea, you can go to the pins at the ECU. I got the picture somewhere. Lemme find it. Anyways, you just ring the wires to each other, meaning that you just measure the resistance between the 2 wires. this will tell you if the signal from the CAS is getting to the ECU. Basically you are checking the wires in between for a short.



There, test pins N and P, and then pins T and Q. Just check with a multimeter set to ohms.



Ohh yea. To find the pins you are looking for pull the big plug of the ECU. The pins are lettered looking at them from the wire side, not the side that plugs into the ECU. To find those pins you start counting from the top right. This is A direcly under it is B and to the left of A is C. Just count until you find the pins you need.


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