I need help!! Tuning issues... Spark??
Check your harness for your cam position sensor/MAP sensor, maybe too tight at the back of the motor/getting pinched, as why you're seeing cutout at 4K rpms.
Also, do the Crank Relearn Procedure again, as that must be done when you install a new motor. Doesn't matter if you have the same PCM, you have to allow the PCM to learn the new reluctor so it can match up the firing sequence properly, and also check the sensor and MAKE sure its not damaged.
1st, the cam sensor won't matter at WOT. Matter of fact, you can unplug it and all it will do is be a little harder to start. It will perform normally once started though. It will kill the tach though.
2nd, a crank relearn has nothing to do with performance. All it is there for is misfire information. It will not, under any circumstances, affect performance, whether it is performed or not.
The ONLY TIME misfire detection is prevented is IF THE CRANK RELEARN CODE IS SET. You can go in and turn the code off, and you will still have misfire detection.
Now, as far as the problem you're having, without a tune, runlog, and dyno graph, it's anyone's guess. I would suggest you crank up the coil dwell and see what that does. It shouldn't need it being an NA motor, but hey, I've run into dumber stuff.
Could be a valve spring issue too. Again, hard to diagnose with no real data.
1st, the cam sensor won't matter at WOT. Matter of fact, you can unplug it and all it will do is be a little harder to start. It will perform normally once started though. It will kill the tach though.
2nd, a crank relearn has nothing to do with performance. All it is there for is misfire information. It will not, under any circumstances, affect performance, whether it is performed or not.
The ONLY TIME misfire detection is prevented is IF THE CRANK RELEARN CODE IS SET. You can go in and turn the code off, and you will still have misfire detection.
Now, as far as the problem you're having, without a tune, runlog, and dyno graph, it's anyone's guess. I would suggest you crank up the coil dwell and see what that does. It shouldn't need it being an NA motor, but hey, I've run into dumber stuff.
Could be a valve spring issue too. Again, hard to diagnose with no real data.
Adrian
Adrian
First off, the crank relearn is so the computer can detect variations in crank shaft speed at higher RPMs, not idle.
Second, you can turn the code off, and never ever worry about it. You'll still have misfire detection, as it's not interrupted UNLESS THE CODE IS SET.
PS you don't need a tuning book, just a thorough understanding of OBDII.
First off, the crank relearn is so the computer can detect variations in crank shaft speed at higher RPMs, not idle.
Second, you can turn the code off, and never ever worry about it. You'll still have misfire detection, as it's not interrupted UNLESS THE CODE IS SET.
PS you don't need a tuning book, just a thorough understanding of OBDII.
Guess what it was, the connector that plugs into the crank position sensor had a loose pin and that was causing it....
We fixed the pin and drove the car, after it fully warmed up..
The car for once, pulled straight up to 6000rpms, smoothly...
I made a pull in 2nd gear and 1st gear. it seems solid. So Issue fixed (unless this occurs again tomorrow)
But Im so happy its fixed...
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