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Blown?

Old 11-19-18, 08:05 AM
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Blown?

whats up guys. So I think I might have finally pop my first 13b lol

i was having some fun and was doing a few wot pulls which felt strong.
but when I stop at the red light the car didnít want to idle normal.
I take off at the light and drive home 40miles and the car drove fine and no issues
on the highway but once I hit the streets and every red light the idle was super
funky.

heres a before and after idle video.

i havenít had time to do a compression check or anything with work.
but curious if yíall have seen a car do this and if yíall think itís a compression issue.

Before

after
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Old 11-19-18, 08:09 AM
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Question

Engine vacuum? Doesn't sound good. Peak knock of 113 common for your car? Peak air temp of 78C is horrible, I would not recommend flooring an FD if you were pulling away from a light with air temps that high (172 F oh man). What boost levels?

Edit: anddddd peak water temp of 114 is likewise no bueno. You AZ boys need a massive radiator as well as two large (think SBG kit) oil coolers along with other magic to make sure your FDs run happy on the surface of the sun over there.

Last edited by GoodfellaFD3S; 11-19-18 at 08:13 AM.
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Old 11-19-18, 08:30 AM
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It could be something simple, but do a compression test first then go from there. But, it does sound blown unfortunately. Confirm it and go forward.

You don't need a fancy rotary compression tester, a plain cheap piston tester can tell you if it's blown.

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Old 11-21-18, 09:04 AM
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I had one that had a chipped seal. It was hard to start and idled funny but would rev up perfectly fine. It also still pulled like mule when you got on it. I think the higher revs helped it seal to the point where the compression loss was almost unnoticeable. When I disassembled the engine one rotor had the slightest little chip in it.

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Old 11-21-18, 11:12 AM
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^Yep, that's the most common way an apex seal breaks. The tip snaps off and that's all she wrote.

That's also why you can't diagnose a blown motor by looking through the exhaust ports - you can't see the edge.

At higher RPM the rotor is spinning fast enough that the compressed air/fuel doesn't have enough time to leak past that gap to the other rotor face.

But, the big thing is it ain't getting any better. You'll have to tear into it.

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Old 11-21-18, 01:00 PM
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Outside of the running issue, you really need to get your temps under control. Those numbers are extremely high
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Old 11-21-18, 11:39 PM
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that sounds blown to me, I would definitely start with a compression test.
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