Need help. Engine swap no start

H8IMPORTS

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Long time member but I haven't posted in awhile. I just got me a 99 cobra and had it about a week and half and the engine locked up. I got an 2003 cobra engine and swapped it in. Used everything from the 99 onto the engine reluctant wheel and all. I only used the stock 2003 long block. Now the car will turn over but not start. The tach isn't working and it's throwing codes saying no rpm. I know the 2003 doesn't have place for knock sensors but I'll turn them off when I get it tuned. I have a Vortech going on it as soon as I get running. Wanted to get it running before the supercharger. Any help please. I'd like to get back into a Cobra. Thanks
 

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BlackStang00

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If it’s not getting rpm signal then it’s likely the crank position sensor. The clip is known to break and slide off just enough to not make contact.
 

01yellercobra

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Pull the crank sensor and look through the hole. Make sure you can see the teeth on the wheel. The different years use different reluctor wheels due to differences in the crank gears. I don't remember which uses thick and thin wheels, but if it's the wrong offset it won't line up with the sensor.
 

H8IMPORTS

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Pull the crank sensor and look through the hole. Make sure you can see the teeth on the wheel. The different years use different reluctor wheels due to differences in the crank gears. I don't remember which uses thick and thin wheels, but if it's the wrong offset it won't line up with the sensor.
OK thanks. Didn't know that. I thought putting the old one on the would be best. Maybe not. Thanks.
 
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hotcobra03

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Long time member but I haven't posted in awhile. I just got me a 99 cobra and had it about a week and half and the engine locked up. I got an 2003 cobra engine and swapped it in. Used everything from the 99 onto the engine reluctant wheel and all. I only used the stock 2003 long block. Now the car will turn over but not start. The tach isn't working and it's throwing codes saying no rpm. I know the 2003 doesn't have place for knock sensors but I'll turn them off when I get it tuned. I have a Vortech going on it as soon as I get running. Wanted to get it running before the supercharger. Any help please. I'd like to get back into a Cobra. Thanks


what code says no rpm signal?

po1000 scanned before drivecycle complete
po602..see note 11 vin block reprogramming
po1633 kam power..check fuse 21 hot at all times engine bay 5amp..check pin 55 at pcm for 12volts..
 

H8IMPORTS

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Checked reluctor ring, looks fine close to the sensor like it should be, spins with motor, sensor replaced, didn't change still no rpm, checked plug, no power at plug, checked fuses and power and ground at pcm, has all it needs according to wire diagram, not sure where to go. The reluctor wheels are different from the 03 and the 99 I swapped in. Could it be the reluctor wheel or does it seem to be more something with the plug not getting power at the plug?
 

H8IMPORTS

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what code says no rpm signal?

po1000 scanned before drivecycle complete
po602..see note 11 vin block reprogramming
po1633 kam power..check fuse 21 hot at all times engine bay 5amp..check pin 55 at pcm for 12volts..
what code says no rpm signal?

po1000 scanned before drivecycle complete
po602..see note 11 vin block reprogramming
po1633 kam power..check fuse 21 hot at all times engine bay 5amp..check pin 55 at pcm for 12volts..
I'll check that. The tach isn't working so no signal (or i could be wrong).

It's at my buddy's shop and he said that it wasn't getting one. I'll ask why he said that for sure.
 

hotcobra03

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Checked reluctor ring, looks fine close to the sensor like it should be, spins with motor, sensor replaced, didn't change still no rpm, checked plug, no power at plug, checked fuses and power and ground at pcm, has all it needs according to wire diagram, not sure where to go. The reluctor wheels are different from the 03 and the 99 I swapped in. Could it be the reluctor wheel or does it seem to be more something with the plug not getting power at the plug?

power at crank sensor plug?

There isn't power at this ..it produces a signal sent to pcm
 

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