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I'm not a total noob, but the language used on this service report is confusing. Car is bone stock and under warranty. Went it for a power loss issue under acceleration. They checked all hoses, clamps, etc. and found nothing but did see an issue with cylinder 2. From what I see, there was an RPM drop between second and third gear on cylinder 2, with a misfire probably being caused by a cracked plug (tracking marks). I see cylinder compression tests here too, but what I can't tell is this:

We're the cylinders passing compression before the issue was resolved? Just misfiring with good compression?

What is the meaning of ppt hd?

What is Hd1, Hd2, etc.? (Not talking about cylinders because it goes up to 8)

Why do some of the hd1, hd2 etc. have Y and some have N next to it? (Assuming this is yes and no).
@FORD

Thanks dudes! Any help is appreciated. Like I said, not a total noob but not a lifelong gearhead either.


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PPT HDx are read outs are from the Scan Tool on the tests performed. No clue what they mean as I don't have the tool.

I can break this down and tell you they checked codes, ran a Relative Compression Test, and ran a Power Balance test

Both tests use Mode 6 Data (scan tool special data) to look at the crank position sensor as each piston moved. Keep in mind that down at a millisecond scale a RPM chart looks more like waves then a straight line

The Relative Compression Test runs while the vehicle is cranked with no fuel or spark. It looks for a slight slow down on each cylinder's compression stroke, and compares all the cylinders. If a cylinder has a leak, the slowdown is less because it doesn't have to do that much work compressing the air. This lets the Tech know to check that cylinder for damage. Your's passed.

Power Balance looks for the speed to increase with each power stoke for all cylinders and if the speed up isn't uniform, one or more cylinders could have an issue igniting fuel. Your car had an intermittent issue with Cylinder #2 not adding power all the time under engine load.

Also a P0302 historical code was present. P0302 points to a misfire in Cylinder #2, and the 'historical' means your computer thought it was an issue in the past, but not a big deal now.

At this points all the data pointed to good engine that can't always make the Boom-Boom on Cyl #2.

Found a bad plug on Cyl #2 and replaced it.
 
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