CPS question

[mk3sons]

hey guys i just got my rebuilt motor all installed and it has no spark . I was wondering if the cps had anything to do with not having ANY spark, or would it just screw up timing?

This is my first ever foray into any serious engine work but i checked all the grounds and i am not sure what to check next but i am 100% sure my cps in way off i just don't think it will solve my problems.

 

[hvyman]

well if the cps is installed incorrectly its not going to start.

 

[mk3sons]

well if the cps is installed incorrectly its not going to start.

i know that i but will it installed a little off (or a lot) cause NO spark?

 

[TurboStreetCar]

If the cps is working you will get spark, whether its properly timed or not, youll have spark.

 

[mk3sons]

If the cps is working you will get spark, whether its properly timed or not, youll have spark.

thank you sir that's what i wanted to know, but now i cant figure out why i don't have spark. i think its the ignitor since i have power before it and none after it. does this make sense to you guys?

 

[TurboStreetCar]

Where don't you have power? The ignitor doesn't output power, it switches ground to trigger the coils.

Check the resistance in the CPS coils and make sure its within spec, thats the only way to test it. If the coils are good, the only other CPS related issue would be the wiring witch is common. You could try rewiring the CPS to the harness if you suspect the stock connector is causing the bad connection. If you decide to do this do it one wire at a time as the wire colors are different on either side of the connector.

Wiring diagram of ignition system can be found here.

 

[mk3sons]

Where don't you have power? The ignitor doesn't output power, it switches ground to trigger the coils.

Check the resistance in the CPS coils and make sure its within spec, thats the only way to test it. If the coils are good, the only other CPS related issue would be the wiring witch is common. You could try rewiring the CPS to the harness if you suspect the stock connector is causing the bad connection. If you decide to do this do it one wire at a time as the wire colors are different on either side of the connector.

Wiring diagram of ignition system can be found here.

what the hell i am so confused! i know there is power going into the ignitor, but i have no power at all on the plugs that attach to the coils.(harness plugs not on the coil.) do you know what the problem might be?

EDIT: my ignitor passed the power source line check but failed the power transistor check. would that cause my to get no spark?

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=IG&P=15

 

[TurboStreetCar]

If your sure the transistor test was done properly then i would say its safe to say your ignitor is bad.

The momentary continuity your supposed to be seeing in the ignitor is the trigger for spark. If you don't have that "switch" theres nothing triggering the coil, if the coil isn't triggered it wont create a spark.

If you dont have power going to the coils, trace the harness back. IIRC theres two plugs that go the to ignitor, one is from the TCCS and the other goes to the coils. Check to see if you have power to the ignitor? Might have a common problem with other circuits that you have not found out about yet.

On the main plug that goes to the coils (4 pin connector) there should be power on the (IIRC) Black-orange stripe wire.

I forget how the stock harness is routed as i made my own harness for my standalone but trace the coil harness back (specificly the black/orange power wire) and see what you find. Test the connector AND the wire, a bad connector will test bad when, really the wire has power.

 

[whitemike]

If you dont have power going to the coils, trace the harness back. IIRC theres two plugs that go the to ignitor, one is from the TCCS and the other goes to the coils.

Also, triple check your ground on the coil packs! I just disconnected mine and have a fear of forgetting to re-connect it. I can just see myself troubleshooting for hours when I knew the answer in the back of my head.

-Mike

 

[TurboStreetCar]

A missing ground would appear as a possible incomplete circuit but power would still be visible at the coils.

In my experience the ground strap on the coil packs is a redundant ground and doesn't effect engine operation. I have run N/A valve covers with no place to bolt the coil packs down and no ground strap without issues. Remember this is in my experience.

 

[mk3sons]

If your sure the transistor test was done properly then i would say its safe to say your ignitor is bad.

The momentary continuity your supposed to be seeing in the ignitor is the trigger for spark. If you don't have that "switch" theres nothing triggering the coil, if the coil isn't triggered it wont create a spark.

If you dont have power going to the coils, trace the harness back. IIRC theres two plugs that go the to ignitor, one is from the TCCS and the other goes to the coils. Check to see if you have power to the ignitor? Might have a common problem with other circuits that you have not found out about yet.

On the main plug that goes to the coils (4 pin connector) there should be power on the (IIRC) Black-orange stripe wire.

I forget how the stock harness is routed as i made my own harness for my standalone but trace the coil harness back (specificly the black/orange power wire) and see what you find. Test the connector AND the wire, a bad connector will test bad when, really the wire has power.

i checked for power i do have power on the plug going into the igniter

Also, triple check your ground on the coil packs! I just disconnected mine and have a fear of forgetting to re-connect it. I can just see myself troubleshooting for hours when I knew the answer in the back of my head.

-Mike

i checked the grounds like four thousand times (i counted)


so if i understand correctly i should need a new ignitor?

 

[TurboStreetCar]

i checked for power i do have power on the plug going into the igniter


so if i understand correctly i should need a new ignitor?

Because you stated it failed the test I would believe so. What about the power to the coils? You could have a brand new ignitor but without power to the coils, You're still dead in the water.

 

[mk3sons]

Because you stated it failed the test I would believe so. What about the power to the coils? You could have a brand new ignitor but without power to the coils, You're still dead in the water.

im not getting any power to the coils i have no idea what to do now...:: angry :::3d_frown:

 

[TurboStreetCar]

If you dont have power going to the coils, trace the harness back. IIRC theres two plugs that go the to ignitor, one is from the TCCS and the other goes to the coils. Check to see if you have power to the ignitor? Might have a common problem with other circuits that you have not found out about yet.

On the main plug that goes to the coils (4 pin connector) there should be power on the (IIRC) Black-orange stripe wire.

I forget how the stock harness is routed as i made my own harness for my standalone but trace the coil harness back (specificly the black/orange power wire) and see what you find. Test the connector AND the wire, a bad connector will test bad when, really the wire has power.

 

[mk3sons]

ok nosechunks is the best! thank you, i figured it out is was a bad connector.. im so dumb.. i tried starting it and it started for little i got a big poof from the intake and it stalled im thinking timing though. so back to the cps i go!

 

[TurboStreetCar]

Sounds like timing, Throw a dab of white out on the zero line on the crank pulley, Makes a world of difference trying to find it when its light out.