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Do I need a new engine?

Old 02-01-19, 08:35 PM
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Do I need a new engine?

What happened to my engine? Mechanic got my car running after replacing the TPS, his secretary said to take it home and see if it's driving like it was before. So I drove it an hour drive home and then found out I was supposed to just go around the block. She called and said it wasn't put back together and I need to bring it back.
Long story short I didn't take it back, did a lot of my own troubleshooting since it just had cold start issues. The day I found the air temp sensor was malfunctioning in cold temperature is the day I took a really sharp corner, heard a ping ting ting sound like a bolt came off and bounced around. Few weeks after that it slowly lost performance on the interstate until it barely goes now.
All of my spark plug holes test at 60psi, which seems odd since I read when seels go bad the compression varies greatly between spark plug holes.
Is my engine shot? What could cause this to happen? There's plenty of oil. It's there a part that could have came loose to loose compression like this?
Here's a video of my compression test results and my guages when it's running.
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Old 02-02-19, 05:09 PM
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Watching the compression test gauge as close as I can on youtube, starting from the second time you show the compression test gauge, the three pluses / rotor don't look to all be 60 psi. It's especially evident on the last one of the gauge shots, just before the 1 minute mark. That one looks like one is 60 psi, but two others are closer to 30 psi or maybe even a little low of that. What that means is that one side of the rotor is making good compression, but the other two probably aren't.

Maybe someone with more rotary experience that me can chime in here, but from what I've read that looks like the sign of at least one dead apex seal. It only takes one dead apex seal to kill two sides of the rotor, which would leave one good side at good compression.
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Old 02-12-19, 07:41 AM
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You can try a small (dribble) of ATF fluid in the spark plug holes (SMALL AMOUNT) And see if the apex seal is just stuck perhaps? Turn it over several times and test compression again. It's difficult to test compression with a standard compression tool. A rotary specific tool would be ideal.

-M
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