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hey. so i have 3 wires for the crank sensor.
Ground
Battery +
Signal
Here are the steps taken to test crank sensor.
1-ignition key on
2-battery volt 13.0
3-disconnected coilpacks
4-meter to DCV
5- red probe to crank signal wire
6- black probe to ground (from the crank harness)
7- manually turned the motor and i get........
0.03 when crank wheel is not in-between crank sensor.
0 when wheel is in between sensor.
the crank is a hall effect sensor. that should only be 0-5V right?
So, yes, you should have 5v on that crank signal wire... brown with a green tracer. With the KOEO and the sensor unplugged check the signal voltage. If 5v, the problem is the sensor. No 5v, problem is in the wiring as you appear to have some resistance on that signal wire. I have a crude wiring diagram which I'm looking at. It shows pin 43 at the ECM as the 5v for the crank. The crank, cam and air temp sensors share the same ground. Check for 5v at pin 43.
Forgot to mention... use a good block ground for your meter for all your testing, not the sensor ground wire.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
i made a mistake.
i had the signal wire cut and tested it that way which gave me a bum reading of .03.
fixed the wire. got a 5V reading from signal wire.
so. cam sensor reads good, crank sensor reads good.
started the car and it is still on 2 and 3 cylinders.
still no spark at 1 and 4.
what is next to test?
signal wire for 2 and 3 reads .7-.8v
signal wire 1 and 4 reads .4.-.3
Good work... this puts us back at square one. You have tested the 1-4 coil circuit. Test the 2-3 coil so we have comparative values to look at. Use a good block ground point for your meter ground and test each wire KOEO plugged in and unplugged.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Ok... based on everything done to date, the engine should run on all 4. If coil 1-4 fires with the driver from 2-3 then the coils are good and so are the grounds. If the ECM checks Ok and works in another Evo8 then the drivers for both coils are good. Only other thing is you ran a proxy wire from the ECM pin 10... the schematic i'm looking at says pins 11 and 12 are the coil drivers, and no joy. This zero's me in on the pins within the connector at the ECM and the coil for the 1-4 signal wire. Check them extremely close for bent or corroded pins. Check the female pins for drag, that is the male pin is firmly seated within the female pin and the male pin pins don't back out when the connector is connected to the ECM and coil. I mentioned it before, you can splice the 2-3 driver wire into the 1-4 and have the single driver work for both coils. You'll be up and running but it would be better to fix the problem.
If you get the chance, I believe the signal wire has a bias voltage on it, unplug either coil and with the KOEO let me know what the voltage is on the signal wire. Thanks.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Hello.
Thank you for the suggestions honestly this is my last hope. everyone else has failed to help me.
Also a learning process for me.
If i splice 1 and 4 to 2 and 3. would is safely be able to drive? this would cause misfire on 1 and 4 correct? i want to be able to take it to my shop so i can get to test more often.
If it was my car, I would continue to work on the fix. I offer the suggestion only as an alternative to try. I would surely test the work around before going out with it. IMO I see no reason it won't work as a temp fix. With a little more work you will find that wiring issue. The signal is there it just has to get to the coil via the signal wire.
I'll continue to think about this and offer help.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
i will try to jump the wire and see how the engine takes it. shop is 20 min away. the signal is low compared to coil pack 2 and 3.
i just dont know what would cause that other thn the ecu.
Thank you!!!
Correct.
I also tested both ecu my own way.
maybe you can tell me if its accurate or a good way to test.
KOEO i disconnected the ecu connector.
pin for 1 and 4 read 6v
pin for 2 and 3 read 6v
Alright so i got the car towed to my shop where i can now run any test to fix the issue.
I jumped the signal wire from 2&3(spark) to 1&4(no spark)
Looked at the coil pack 1&4 made sure it got spark by connecting a extra spark plug at the end of the coil pack. It sparks.
Put it back in the motor and made no difference to the motor. Sounds the same.
Whats the next test. Cam and crank sensor are tested and working.
When you swap coils, do you leave the plug wires attached to the coils or plugs. Trying to make clear, are the plug wires always attached to the same coil when you move them?
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
I had nothing but time so i went ahead and tested all coil packs i had. i have 2 sets of 4 coil packs and they all sparked. I feel better when i see the spark myself.
definitely not coil packs.
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