no spark issue

[grandprixgtp_93]

i have a no spark issue due to no signal from the crankshaft position sensor any help would be nice i checked the sensor already and its good dont know what todo now

[bszopi]

How did you check the sensor to make sure it was good? Also, did you inspect the wiring between the sensor and ICM for damage?

[pocket-rocket]

Also check the ICM for power. It could also be a bad ICM.

[85erbirdie]

find the wire diagram check for continuity or that cuircut between sensor and harnes also doulbe check fuses first always basics first and double check the type of sensor it has so you know the correct test to use ill see if i can find it and let you know

[grandprixgtp_93]

i used a resistance check to check the sensor the spec was 800 to 1200 ohms i was at 1000 so i know thats good my icm is good i have 1.3 mega ohms through the purple and yellow signal wire tho im thinking maybe when i made my wire extensions for the relocation i might have hooked the purple to yellow and yellow to purple i know this will cause tho no spark but will it cause the resistance issue so i know thats what i need to fix?

[85erbirdie]

did it work did it work vroom vroom???

[grandprixgtp_93]

ok so after countless hours we finaly tracked the issue to the crankshaft position sensor air gap to the reluctor wheel of the crank has anyone had this issue b4? i need to get this figured out ive been trying to file down the part of the plastic that sits on the block to close up the gap

[Superdave]

That shouldn't be an issue, the gap should be about .030" but will work fine till about .050" or so.

Am i reading it right.. you extended the CPS wire? If so then that's your problem. You cannot do that. Swap in a un-modified one, i bet it fires right up.

[grandprixgtp_93]

well i mounted my coils on the metal support above the radiator so i had to extend the wires byr about 2 feet i used a larger gauge wire to compensate for resistance drop and also my low voltage issue is with the scope plugged into the back of the sensor when its in the block

[Superdave]

trust me, that doesn't work.

At the very least get 2 stock CPS harnesses and solder them together, that is rumored to work.

[grandprixgtp_93]

well i know the air gap is way to big its at about .25inches and according to my teachers who are ASE master technicians and my high performance teacher my wire extensions wouldnt cause the issue im having and redzmonte has the same coil mount system i have and he would of had to extend his wires some how for it to work

[Superdave]

well, me who is an electronics engineer and has been building these engines for the last 15 years knows better. I have extended the CPS wires in the past and I know exactly what it can do. I've seen it work and the engine run fine at idle but the timing was about 10 degrees retarded which caused a massive power loss at WOT. That may not cause your no-start condition but it will very likely cause the same problems with the CPS signal itself being retarded.


If there is a .25" gap between the CPS and the crank you have the wrong sensor. No sensor should be that far out of manufacturing tolerance. Post up a picture of it.

[grandprixgtp_93]

i dont see how a little extra wire would cause this problem concidering redz and hayes have relocated their coils and would have had to extend the wires and their cars run fine and the crank sensor is correct its exactly the same as my old one

[bszopi]

Did you twist the new wiring the required amount, like the original?

[grandprixgtp_93]

i did twist the wires i might have twisted tighter thah the original i wouldnt think that would matter would it?