spark plug firing WITHOUT engine turning over
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spark plug firing WITHOUT engine turning over
I just rebuilt the engine and changed a bunch of parts. It has NOT ran yet. The problem is that when I turn the car to the RUN, (not start) position I hear the spark plugs firing all at once. I pulled a wire off, inserted an old plug, and grounded it to confirm this and the plug constantly (continually) fires WITHOUT the engine turning over. I checked one from the other bank and same thing. Only thing I can think is bad (new) Crank position sensor. Also, I tried to hook two different scanners up to the port and they both said "unable to establish link" and the dash says "reduced power mode".
Thanks in advance.
Thanks in advance.
Last edited by Talons24; Aug 5, 2020 at 05:48 PM.
Thread Starter
Intermediate
Joined: Aug 2014
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Thank you for that!!!!!!! I will see if my injectors were also firing and check my grounds and sensors. I think I got all grounds back on but I will double check. I am leaning towards the computer as I cant even connect to the obd port but I guess I have a day of work in front of me lol.
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Joined: Sep 2013
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Thank you for that!!!!!!! I will see if my injectors were also firing and check my grounds and sensors. I think I got all grounds back on but I will double check. I am leaning towards the computer as I cant even connect to the obd port but I guess I have a day of work in front of me lol.
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Well, I checked all the wires to make sure they were on the right thing. They were. I disconnected everything I connected, Crank sensor, cam sensor, Oil sender, Knock sensors, oil temp, Intake, starter, Alternator, oil level, and one coil bank. I didnt disconnect transmission or differential. With EVERYTHING front end disconnected, it still constantly sparks without the engine even turning. Run position only. Only thing left is PCM I think. Sooooooo, I will change that when it arrives and hopefully that solves the issue.
Thread Starter
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just noticed that the tach is not moving on cranking the car over. so, I am definitely leaning towards bad CPS. I am 99.995% sure I have the timing marks lined up correctly on the timing chain and crank gear. I have built MANY motors in my day.
Last edited by Talons24; Aug 16, 2020 at 01:20 PM.
Thread Starter
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Joined: Aug 2014
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It was a bad Crank position sensor. I replaced it when building the engine but apparently the new was bad. So I replaced it with another one and it started and idled first crank. Damn car was driving me nuts. Now it feels like a raped ape. Squealed the tires at a touch off idle. This is gonna be fun!!!!! lol
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Joined: Jul 2010
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It was a bad Crank position sensor. I replaced it when building the engine but apparently the new was bad. So I replaced it with another one and it started and idled first crank. Damn car was driving me nuts. Now it feels like a raped ape. Squealed the tires at a touch off idle. This is gonna be fun!!!!! lol
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