kb2727

I've used this model given in an early post of mine to try and diagnosis my problem. I just can't get the car to show any signs of spark.



1. power: battery ->ignition switch -> main relay -> 12v @coils



2. signal: crank angle sensor = rpm signal -> ecu -> coils -> plug wires -> plugs



Battery is brand new and charged, when I turn the ignition switch I get 12.4V at the coils. I've put in good Coils/ignitors, plug wires, and new plugs to rule them out. I've also swapped in a good ECU and MAF. Resistance measurements from the crank angle sensor are in spec, and if I pop the cover off the crank angle sensor everything is moving as it should. What else is left? This is very frustrating.



My test setup is using a wire wrapped around the threaded portion of the plug, and grounded to the chassis. Resistance between the plugs surface and battery negative is almost 0, so it is grounded. I'm using one of the leading coil wires with a leading plug, and have the EGI fused pulled during testing.



Is there something else out there that would be causing this problem?? Sensor? Fuse? Anything?

j9fd3s

heres one for ya, ran into this yesterday.



89 na, started right up, ran good, drove it around a bit, left it idling to wash it. car dies. wont restart.



ok its prolly out of gas, it was a trade in, etc etc



we put gas in it, nothing. check fuses, all fine. check a plug, nasty, but dry. afm moves freely....



it turned out to be the CAS plug, it looks fine, but its flakey. cleaned it out, car started right up, and runs really nice

kb2727

Sounds like a good place to look more closely. I'll do that this afternoon and see what I get from it. I'm also going to double check the wires at other points to make sure there are no damaged ones. Thanks.

kb2727

Well another day of working on trying to get this thing going and still no luck. I cleaned the CAS harness as suggested.. still nothing. I also did a pain in the *** trace of each signal wire from the ECU going to the CAS, trailing and leading coils/ignitors. All the wiring checked out as good. What now? I'm desperate for any suggestions.

kb2727

WE HAVE SPARK! I didn't think this was part of the spark system, but I've been testing the spark with the EGI fuse out. As soon as I put it back in, plenty of spark. I guess no one caught that up above in my first post when I said I was testing with the fuse pulled. Next step... getting it to start.

j9fd3s

is the ecu getting power? does it do ANYTHING? can you get it to spark, with the plugs outside the engine?

kb2727

I'm getting spark now outside the engine like I said ^ .... it was because I had the EGI fuse out that I wasn't seeing any spark outside the engine. I thought it would only cut fuel and not spark too. ECU is getting power though. 12.4V measured. I'm going to deflood and try to start again tomorrow.

Dev

I having sortof the same problem!

except now I have a spurting idle

j9fd3s when you say CAS are you refering to the crank angle sensor?

kb2727

yes, CAS was referring to the crank angle sensor

hillbilly

damn man, you're hard core...