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Discussion Starter · #1 · (Edited)
All cylinders compression is around 275 psi (all measurements were taken after 3-4 compression strokes and the compression reached around 300 psi if I kept cranking)
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Plugs 1&2 look terrible and they don’t cause any misfire. Plugs 3-6 look normal.
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deposits on 1 and 2 don't look very good
 

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All cylinders compression is around 275 psi (all measurements were taken after 3-4 compression strokes and the compression reached around 300 psi if I kept cranking)
View attachment 117276 View attachment 117277 View attachment 117278 View attachment 117279 View attachment 117280 View attachment 117281

Plugs 1&2 look terrible and they don’t cause any misfire. Plugs 3-6 look normal. View attachment 117282 View attachment 117283 View attachment 117284 View attachment 117285
Are these dry or wet compression scores?

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Discussion Starter · #5 ·
Are these dry or wet compression scores?

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Dry I guess. I didn’t add a single drop of oil in the the cylinders. Just cranked the pistons only using the starter motor and bypassing the ignition system.


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Discussion Starter · #6 · (Edited)
DZ,
How long did you keep cranking to get your compression readings? As I said if I kept it cranking the compression went up to 300 PSI.

What I didn’t do was to remove all the spark plugs, instead I removed one at a time for each test. And I did open the throttle plate.


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Well, all spark plugs need to go, they are not good (I am not 100% sure these are legit iridium spark plugs ). Compression reading are way too high. no wonder your engine pings. You need to clean that carbon from combustion chamber asap.
Also this time it looks like there are no lean condition like it was before. Cylinder 2 looks like running rich.
Usually I crank 8 times.

This is how healthy engine and spark plugs should look (running little rich):

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Discussion Starter · #8 ·
Well, all spark plugs need to go, they are not good (I am not 100% sure these are legit iridium spark plugs ). Compression reading are way too high. no wonder your engine pings. You need to clean that carbon from combustion chamber asap.
Also this time it looks like there are no lean condition like it was before. Cylinder 2 looks like running rich.
Usually I crank 8 times.

This is how healthy engine and spark plugs should look (running little rich):

View attachment 117288
The compression readings are too high because I didn’t removed all the plugs AND opened the throttle plate?

I will need to do it again.


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The compression readings are too high because I didn’t removed all the plugs AND opened the throttle plate?

I will need to do it again.


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No, it is high because of carbon, opening TB plate will not affect compression readings by much. Don't waste your time.
 

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where did you get the plugs from? On a somewhat related/side note, have you taken off and cleaned the EGR and PCV system at all? All the carbon from the oil being burnt gets recirculated and can build up a LOT.
 

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test done properly is remove all the plugs and crank the engine over with it being at operating temp with fuel disabled. Sounds like you are doing something similar. What engine temp?
 

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Discussion Starter · #12 ·
test done properly is remove all the plugs and crank the engine over with it being at operating temp with fuel disabled. Sounds like you are doing something similar. What engine temp?
The fuel system and ignition were disabled.
The engine was at normal operating temp.
The only things I forgot is to open the throttle plate and remove all the plugs.

I will try again with the all the plugs remove and the throttle plate full opens.


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Discussion Starter · #13 ·
where did you get the plugs from? On a somewhat related/side note, have you taken off and cleaned the EGR and PCV system at all? All the carbon from the oil being burnt gets recirculated and can build up a LOT.
Amazon, $9.50 each.
Replaced PVC about 16 months ago.
Cleaned EGR about 2 years ago.


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The fuel system and ignition were disabled.
The engine was at normal operating temp.
The only things I forgot is to open the throttle plate and remove all the plugs.

I will try again with the all the plugs remove and the throttle plate full opens.


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oh man....
 

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Discussion Starter · #16 ·
DZ,
I am going to try the MOPAR CC again and this time I will pour one can into cylinder #1 & #2.
Since I don’t have a vacuum to suck all the excess out I will just keep cranking until all the excess shoot out the plug hole and dry it off with a brake cleaner.

Do you think that will be ok? I don’t want to do all the cylinders at the same time because last time I was having trouble starting.


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Like i told you before, you could not start it because there was no compression in cylinders. I don't see a point doing separate cylinders. Everything should be done at once and oil changed.
Also I suggested to use Bluechem Carbon X k1,k2. It is very effective and fast working, cleans valves really good.
 

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Discussion Starter · #18 ·
Like i told you before, you could not start it because there was no compression in cylinders. I don't see a point doing separate cylinders. Everything should be done at once and oil changed.
Also I suggested to use Bluechem Carbon X k1,k2. It is very effective and fast working, cleans valves really good.
Had you try carbon x ?


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Had you try carbon x ?


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I have other ways, but for you and other not advanced users it s a great solution.
 
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