Ls3 swap wont crank and backfires.
https://ls1tech.com/forums/generatio...ngine/1719250-
one-map-sensor-picture.html
https://ls1tech.com/forums/generatio...66-might-have-
swapped-map-sensor-cam-sensor-please-help.html
Last edited by jenfred10; Mar 5, 2016 at 10:51 PM.
We had the cam sensor with extension harness plugged into the map and the map harness plugged into the cam sensor. Car did something very similar to what the op's describing.
https://ls1tech.com/forums/generatio...ngine/1719250-
one-map-sensor-picture.html
https://ls1tech.com/forums/generatio...66-might-have-
swapped-map-sensor-cam-sensor-please-help.html
https://ls1tech.com/forums/generatio...ngine/1719250-
one-map-sensor-picture.html
https://ls1tech.com/forums/generatio...66-might-have-
swapped-map-sensor-cam-sensor-please-help.html
So update. Took it to the dyno place and the mechanic said that crank sensor is not getting enough signal to fire. This is after swapping another crank with reluctor wheel already in place.
24xe = BLACK CS I have read this entire thread, looking for unknowns.
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
Lance. It's Shawn. How's it going?
We had to swap the first half of the firing order for the second half because the cam signal would rise where the 24x would fall. Could that be the issue?
We had to swap the first half of the firing order for the second half because the cam signal would rise where the 24x would fall. Could that be the issue?
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When you say CS you mean Crank or Cam? If crank I think you're onto something.
And you're saying the 24x reluctor can't be positioned wrong?
And you're saying the 24x reluctor can't be positioned wrong?
I have read this entire thread, looking for unknowns.
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
No there is a pattern to it, but has no missing teeth. I goes something like small = S and L = Large.
SSLSLSLSLLSLSLSLSSLSLSLSLSLL
It has to be on correctly or could try to start firing one when the motor is ready for 8 or 2. If it's off to far it will error out or reset the count when the cam signal changes at the wrong moment, but it will start wrong again. Also the sensor needs to match the wheel so he needs the black crank sensor.
SSLSLSLSLLSLSLSLSSLSLSLSLSLL
It has to be on correctly or could try to start firing one when the motor is ready for 8 or 2. If it's off to far it will error out or reset the count when the cam signal changes at the wrong moment, but it will start wrong again. Also the sensor needs to match the wheel so he needs the black crank sensor.
I have read this entire thread, looking for unknowns.
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
One such is that the 58x(my 60-2) requires a GRAY CS.
The GM 24xe requires a BLACK CS.
This change was not stated.
The 24xe is a EVEN tooth TW with NO missing tooth section, thus no position reference EXCEPT for aid to engine balance.
There is also a chance that the coil "sub-harness" is on the opposite side, though mentioned, not confirmed correct.
Another test would be to measure the voltage at the CS ?
Lance
Im using morel 5290 lifters. I don't think it's short travel but has link bar in it. Im not sure which side...I think the driver's side.
Another update..The mechanic contacted one of the GM engineers and claim that he is able to fix the issue. He didn't really specify how but the motor it's assembled ready to be put it on the engine again for the 10th time!!(figure of speech). Please wish me luck and hope this will fix the issue!
Did you get this running? I may be able to come help you out some day and check off some of the simpler wiring issues.
This is Adam, I bought that MAF from you at the fire station, I knew Jeremy M. from high school.
Let me know if you're interested in meeting up some day. I'll bring out my LS1 Nova I just finished up.
This is Adam, I bought that MAF from you at the fire station, I knew Jeremy M. from high school.
Let me know if you're interested in meeting up some day. I'll bring out my LS1 Nova I just finished up.
Curious to know what happened. A (reasonably) easy way to see which arena the problems stem from would to be test this motor on a dyno stand and/ or drop a known good motor into the car. When I was having similar issues I bought a 5.3 off CL to do just that, but fortunately (?) a compression test showed me I had bent valves so I never had to do it.
If the motor runs on a stand then you know the problem is in your harness/ electrical.
If another motor runs in your car or at least hooked to its harness you know the problem is somewhere in your motor.
Not the most practical approach, and would take the better part of a day or weekend, but it would cut your haystack in half and at least give you an idea where your needle is. That's a lot of $$ spent on a new motor to have it simply not work.
I'm relocating my car's computer anyway, if you were in Nashville we could drop it into your car and see what happens. Perhaps someone has a harness and ecm you could borrow for a day.
If the motor runs on a stand then you know the problem is in your harness/ electrical.
If another motor runs in your car or at least hooked to its harness you know the problem is somewhere in your motor.
Not the most practical approach, and would take the better part of a day or weekend, but it would cut your haystack in half and at least give you an idea where your needle is. That's a lot of $$ spent on a new motor to have it simply not work.
I'm relocating my car's computer anyway, if you were in Nashville we could drop it into your car and see what happens. Perhaps someone has a harness and ecm you could borrow for a day.
Last edited by chuckd71; Jun 7, 2016 at 10:49 AM.
