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I’m stumped. Key to the on position, not running, coil is sparking
Ok, I’m confused and my brain hurts. I’m sure I will get it today after I had a good sleep. But just because I’m gonna see if I’m just missing it.
1995 Camaro Z28. Lt1 6speed.
I had it running on the first crank after a rebuild. Security system then went stupid, got that figured out. Then the starter would crank the second I touched the positive cable. Was just a stuck solenoid. Now, I turn the key and I hear it ticking. Fuel pump primes for a second, turns off and fans crank on. Check engine light makes them turn on. I unplugged them to just give a listen to what sounds are coming from the engine bay. It’s ticking. Thought it was the icm, unplugged it and still have the tick. Noticed that my rpm needle bounces every tick. I’m like I got it, single wire to coil. Nope. It stopped when I pulled both connectors but when I plug in the 2 wire connector the ticking comes back. Pulled the coil wire as it’s ticking and numbed my whole arm. Forgot how bad that sucks when the coil gets ya. Happens sometimes lol.
so my queastion is, what would cause that to spark, and really consistent, like you can set a watch to it? Spark is good off the coil unless LT1 sparks harder than most and should have took me down. But the shock was fairly the same as any other coil that got me.
gonna throw an old one on and see what happens. It was good when pulled and I always keep good parts for just in case. I have the 1995 service manual. Also going into that again to see what I’m missing. I feel like I’m totally missing a ground somewhere. If anyone would be able to save me a major headache, and help a guy out great. If not I will be updating this until I get it. I sure this will help someone else in the future.
got fuel to prime a sec
test wire day fuel pressure is well
laptop will no longer connect and neither will any scanner I have?????
all wiring to pcm is good. Tested twice because sometimes I forget things
dlc connector gets power, grounds, and no blown fuses
relays are being checked today, and I will be putting in a computer out of a 1995 firebird 5.7 and seeing if the computer is bad. It’s really the only thing that makes sense. If the computer frooze or locked itself I can’t scan. So would that make the coil ark with key to on position??
sorry for the major huge post. Trying to provide as much info as I can
Re: I’m stumped. Key to the on position, not running, coil is sparking
Yes, ses light is on. But I can’t get my laptop or scanner to connect. I un plugged the Opti wire, and still heard the ticking. That’s when I pulled the 3 coil wires off and it stopped. Put them on and it started ticking. Thought the coil wires where arcing, that’s when I pulled the coil to Opti wire and got the best turbo charge ever. Called it a night after that lol.
oh and my rpm gage was bouncing with the ticks. The rpm signal wire would bounce, no ticks plug the other 2 wire connector in and it sparks. It’s leaving me to think I missed a ground wire somewhere, or pcm, or Opti. I have the old one so I might just throw that on Because that is a free check for Opti issues. And I have a pcm from another 1995 6 speed lt1. First I’m going through this wiring. My laptop read the pcm so I know I had a connection. Pulled no codes at the time. Then I started it. Ran pretty solid for a mild cam tune with stock injectors. Then went to connect again to adjust for 36lbs injectors and bigger cam, and all the other goodies and got nothing.
Re: I’m stumped. Key to the on position, not running, coil is sparking
If unplugging the Opti didn’t stop the sparking, it isn’t a problem w/ the Opti. It was a reasonable check because the PCM uses the pulses from the Opti to time the firing of the ICM/coil, and to drive the tach.
Did you try disconnecting the ICM plug. The white wire from the PCM to the ICM tells the ICM to fire the coil.
I recall you have used Scan9495 in the past. But it would not connect this time?
And I'll move this from “CamaroZ28.com Podcast”. I wish the site owners would close that forum. I'll never understand why people post tech questions there. Just makes more work moving things around.
Re: I’m stumped. Key to the on position, not running, coil is sparking
It did not. I did unplug the ICM, I can’t remember if it made it stop. At the moment I’m going through the wires. I put some thought into that but wasn’t sure. After I get it all back together I will give that a try again. Was dead tired last night and after getting the shocker I just can’t remember. Would make sense if that had a short of some sort sending just the right signals to make it spark. I will let you know how that turns out.
Re: I’m stumped. Key to the on position, not running, coil is sparking
I got this wrapped in black duct tape. One goes to the ICM ( which has me like sweet ) and the other to the block. But if the ground is popping in and out from a bad connection, that might be it. Was all most like peeling dust. Uffff.
Re: I’m stumped. Key to the on position, not running, coil is sparking
I think the drags slicks are gonna be on hold. Fresh wires might keep me from burning her to the ground. That loom I never went through during install of the fresh motor. Now I want to check the wiring to the tail lights and rest of the rear. Only new wires are for the fuel pump
Re: I’m stumped. Key to the on position, not running, coil is sparking
Thank you for the help once again injuneer. I will get her fired up tomorrow and find out for sure if the ICM is also bad. But I threw the other computer in and when I turned the key and fuel pump primed for a few seconds and no fans. I was happy. Laptop read pcm, and loaded the original Camaro tune. So tomorrow I will give a 2nd look to the first time she will get with many more till she’s a 10 second beast lol.
And a note for everyone. When buying a pcm from random people and they tell you it’s from a 95 firebird/trans am. Kick them in the testies. You end up with a Buick road master pcm. Oh well, it’s now a Camaro pcm.
Re: I’m stumped. Key to the on position, not running, coil is sparking
Originally Posted by WhiteWS6
Any update on the issue? Did the PCM end up being bad?
Yes, the pcm was bad. Car runs and laptop and scanner both connect. Gonna data log today, she seems like she runs lean. I just got to remember which way to go with injector size. Up or down. Oh well. That’s what datamaster is for. Logging and tuning. Well tuning with tunercat
Re: I’m stumped. Key to the on position, not running, coil is sparking
Also I will try to make a short video of her running. This is the first motor that just fired up after you turn the key. Maybe 1 crank, and she was a complete tear down.
Pcm was bad from either a short in wiring, or my laptop did something stupid. Either way, if the computer or scanner won’t connect. It’s a bad pcm. I did get a 95 Camaro service manual. I read that it led to replace the pcm, I thought no way, everything works how would that be. Well once again I learned the hard way. When some dude/lady makes the plans, you should probably listen when it says replace pcm. But having the spark off my coil??? That was the crazy thing. Like it thought it was running. Guess what, it don’t do that anymore. And yes, that coil blasted my *** because I’m a nerd and don’t think right so I grabbed the wire and found out the hard way. Coil works lol
most times I use the scan9495. With all the data on the first screen, it makes it easier I think to see the problem. I plan on using the scan9495 For the first log.
08-01-2020, 09:11 AM
