New motor. Car cranks, but wont fire. What could it be?
09-17-2008, 09:11 PM
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New motor. Car cranks, but wont fire. What could it be? I've narrowed it down to 3 possibilities:
*pcm might need a relearn done to it
*crank sensor is bad.
*or crank/reluctor ring problems
We put the new forged 347 in, the car started and ran for 5 or 6 times, then it died and for the last 3 weeks it hasn't started back up. We've checked the ground wires & the fuses. Sparks plugs = no spark. So we think the coils aren't getting power, and that's why we think it could be the crank sensor.
The old motor blew a hole out the passenger side & ruined the starter that was in there. We replaced the starter, and now we think since the crank sensor is so close to the damage it may have just went out.
Any one that wants to chime in will be well appreciated! Thanks
*pcm might need a relearn done to it
*crank sensor is bad.
*or crank/reluctor ring problems
We put the new forged 347 in, the car started and ran for 5 or 6 times, then it died and for the last 3 weeks it hasn't started back up. We've checked the ground wires & the fuses. Sparks plugs = no spark. So we think the coils aren't getting power, and that's why we think it could be the crank sensor.
The old motor blew a hole out the passenger side & ruined the starter that was in there. We replaced the starter, and now we think since the crank sensor is so close to the damage it may have just went out.
Any one that wants to chime in will be well appreciated! Thanks
09-19-2008, 03:46 PM
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^speaking of, we did have a broken end of a ground wire that goes to the back head of the driver side. we easily fixed it, but it didn't do any good 
09-19-2008, 09:55 PM
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well I'm taking my percentages & ordered a new crank sensor through Advance. Should be in tomorrow. But I guess we're going to check for ohms on the old one before I actually go purchase it once it comes in to the store.
Question... I read that:
so basically I'll need someone to do a relearn once, if, we swap out the crank sensor? will the crank sensor go bad if we don't do a relearn and drive the car a little bit?
Question... I read that:
Originally Posted by wait4me
You are supposed to do a relearn anytime you replace the cam or crank sensor, or any rotating mass. It just sets up the pcm to accurately detect missfires and helps with spark octane % table usage. It only takes a few seconds to do with Efilive. It sets the test, then the ecm will make a different rev limit usally 4200rpms and then it measures the difference from accell, then shuts off fuel and checks the decell. Then it sees the actual chain slop on the timing chain.
Glad that worked out for ya. 