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Zero compression in cylinder 5

uscavman

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I could use some help if anyone has any ideas of what I may be doing wrong. The car is procharged. Any help or advice would be greatly appreciated.

During a burnout attempt, I over rev’d the motor. I don't know how high it rev'd but it was well past 8k. Shortly after the incident, white smoke started coming out of the exhaust. I pulled the passenger side oil separator and it was full of oil. A compression test showed zero compression in cylinder 5. All 7 other cylinders showed good compression and were within specified tolerance of each other. Thinking I bent a valve, I pulled the driver side head and cams. After removing the cams, it appeared that the valves were all closed. I put the head back on and a leak-down showed the cylinder was holding pressure again. I replaced the driver-side cams and put everything back together. After starting the car, there was some smoke coming from the exhaust but stopped shortly after the motor warmed up. When I noticed the motor vibrating abnormally, I shut the car down and pulled the DTC codes. I got P0345, P0349, P0390, P0934. Thinking I messed the timing up, I tore everything back down to the cams and tried to retime the motor. This is the first time I’ve removed cams or timing from any vehicle.

  • I have the ford shop manual showing detailed removal and installation procedures.
  • Installation - Driver side
  • Set crankshaft keyway to 5 o’clock.
  • Set the cams in the head in the correct clock position
  • Set secondary timing chain double and single black link on the phasers to the appropriate position
  • Set driver side primary timing chain with black link on sprocket gear timing mark to cam phaser left timing mark. Phaser looks to be in the correct clock position.
  • Rotated crankshaft clockwise to keyway at 12 o’clock
  • Passenger side primary and secondary timing chains set similar to above.
I attempted a second teardown and retimed the motor. The result was more motor vibration. I’m planning the following this week:

  • Pull all the cams and ensure the all cylinders are still holding pressure.
  • Retime the motor
  • I recently discovered there is a crank relearn function on the nguage. I had believed that reloading a tune would reset the PCM.
  • Check all the cam position sensor wiring for any shorts.
  • Compression check each cylinder.
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F1scamp

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Cam timing is off. I would suggest getting someone that has done them to check it over with you. The only step I see missing in your description is after you set the driverside cam, you have to rotate the motor over 360 degrees, then set it to the passengerside position. It seems that's the step everyone misses.
 
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uscavman

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Killeen, TX
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Al
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2016 Mustang GT Premium
Cam timing is off. I would suggest getting someone that has done them to check it over with you. The only step I see missing in your description is after you set the driverside cam, you have to rotate the motor over 360 degrees, then set it to the passengerside position. It seems that's the step everyone misses.

Wow!!! thanks a million, I went back to the manual and saw the step you mentioned, that I missed. I definitely would've have seeked out experienced help with this but I'm currently supporting the US military in Germany. Thanks again for the help!!!
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