Relative compression waveform - Subaru H6

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estilley
Newbie
Posts: 1
Joined: Fri May 17, 2024 3:37 pm

Relative compression waveform - Subaru H6

Post by estilley »

I performed a relative compression test using my PicoScope 2204A with a Hantek high current clamp on my 2002 Subaru Legacy with the 3.0 H6 engine.

My peaks and troughs are all similar but I get weird double and triple humps (double on one bank, triple on the other).

Any idea what these could signify? I have attached a screenshot of the waveform.

Current car symptoms are a rough idle with no check engine light.
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Relative compression waveform
Relative compression waveform

picowight
TwoWaves
TwoWaves
Posts: 172
Joined: Sat Oct 26, 2019 6:45 pm

Re: Relative compression waveform - Subaru H6

Post by picowight »

Not sure about the double humps but 155A seems low to me. Synch a coil and see if it occurs at TDC and if you have 6 humps not 3!

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