So about the no start issue...

pektel

pektel

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My signal to the coils is SUPER WEAK. Hopefully just a corroded ground or something. Going to do some searching tonight.

Anyone have any suggestion as to why the signal would be super weak? Hopefully not pcm related...

Also, anyone know if the coils share a common ground point? And where it might be located?
 
Ground to the coils is switched on and off individually by the PCM. The coils all have a common 12V power connection via fuse F1.12

Is your 12V power to the coils good? How have you determined that the switched ground is weak? A voltmeter would not be fast enough to catch the pulses from the PCM. An oscilloscope is required to measure the primary coil voltages.
 
Joe, I just hooked up a 2 prong test light to the wiring harness (the plug that connects to the coil).
 
joegr said:
Ground to the coils is switched on and off individually by the PCM. The coils all have a common 12V power connection via fuse F1.12

Is your 12V power to the coils good? How have you determined that the switched ground is weak? A voltmeter would not be fast enough to catch the pulses from the PCM. An oscilloscope is required to measure the primary coil voltages.
Click to expand...

To add, no the power to the coils isn't good. I didn't check the coil itself, just unplugged the harness from the coil, and plugged the test light into the harness instead of the coil. Tried to start the car, and noticed the super weak signal. The fuel injector signal is strong (by doing the same test).
 
Found the PCM ground, and the ground for the COP relay. Going to check them out today hopefully.
 
pektel said:
To add, no the power to the coils isn't good. I didn't check the coil itself, just unplugged the harness from the coil, and plugged the test light into the harness instead of the coil. Tried to start the car, and noticed the super weak signal. The fuel injector signal is strong (by doing the same test).
Click to expand...

That's not how you check power to the coils. You measure the voltage on the positive lead referenced to the chassis ground of the car, not the switched ground from the PCM. The PCM turns the grounds to the coils on and off very quickly. The test light isn't a great way to tell how it's doing. I suggest that you compare your result to a known good LS before going too far down this road...
 
Ah, I see. I am not the best at diagnosing an electrical issue. Good to know. No known good LSes in my area, either. No LSes period lol.

I will check your previous recommendation. For some reason the note about the pcm grounding the coils went over my head.

EDIT: Should I just pull the 10 amp fuse and see if I'm getting 12V while cranking?
 
Or do you think i should actually test one of the positive wires to the coil?
 
Maybe I'm not understanding it right. My understanding is that there is a constant 12v signal. The PCM blips the ground to turn the coils on/off. So I should be able to check the power to the coils...
 
The individual coils receive their signal from the PCM to fire at a calculated spark target. The PCM acts as an electronic switch to ground the individual coil primary circuit. When the switch is closed, battery voltage applied to the coil primary circuit builds a magnetic field around the primary coil. When the switch opens, power is interrupted and the primary field collapses, inducing high voltage in the secondary coil winding and the spark plug is fired..

But this happens so fast that a DVOM won't be able to read it.. That's why the oscilloscope..
 
I'm sure he checked battery voltage before he started his testing.. I hope!

Plus I had to copy all that.. Not copy and paste.. So you owe me.. :p
 
Ground for the COP relay is directly behind the passenger headlight. PCM ground is located in the passenger wheel well.
 
take that POS to the dealer or sell it on your own. either way, the car in unreliable and over engineered!!! keep beating your car, and keep repairing your car. Merry Christmas DB!!
 
taurusman97 said:
take that POS to the dealer or sell it on your own. either way, the car in unreliable and over engineered!!! keep beating your car, and keep repairing your car. Merry Christmas DB!!
Click to expand...

Go kill yourself.
 
taurusman97 said:
go back to sleeping with your sister!!! loser
Click to expand...

Quite posting useless crap..

Pete has a very amazing car and I assume it is a small problem he is having.. Diagnosis is cheap if you do it yourself but it is time consuming..

He you even looked at his car? Very amazing.. Why the fu<k would he want to sell it?

Did you sell your car and get a Prius? Is that why your so pissed at everyone?
 
Wow, someone has some serious grit in the mangina... :rolleyes:

Anyone even know who this guy is? Looks like he's been around since 08, but I don't remember him.

I must've either verbally pwned him or slept with his sister, and completely forgot about it. :gr_devil:
 
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