I just did a compression test on my stock ls/vtec

Cyl#1 175 psi
Cyl#2 170 psi
Cyl#3 180 psi
Cyl#4 170 psi

I did this test with the engine cold cause it doesn't idle so I couldn't get it to operating temp and I wasn't sure if I was supposed to do it at WIDE OPEN THROTTLE or not so I did it anyways.

Can anyone tell me if these readings are close to what I should be getting and if I am supposed to be doing this test at wide open throttle cause I thought that all you needed to do was disable the ign. and crank the eng. over and I got readings of about 110-120 psi and I thought that was low.

 

anyone?

 

1. the engine needs to be up to temp. you're not getting correct readings otherwise.
2. the engine needs to be at WOT while you crank the engine
3. remove all spark plugs not one at a time

 

what kind of pistons are you running?

 

My understanding is that the absolute values don't matter so much as long as they're not amazingly low (120psi) and as long as they're within 10% of each other.

Notwithstanding that the engine wasn't warmed up, those numbers look fine to me.

 

Hey, I have the same problem with the compression test with my 97 civic EX (stock D16Y8)

Cyl#1 175 psi
Cyl#2 165 psi
Cyl#3 120 psi
Cyl#4 170 psi

The cylinder 3 looks bad, but the motor wasn’t warmed up, so I think that’s a problem, other than that, I think it needs a valve adjustment; I don’t know if that would help since I’m kinda noob with this
What you think?

 

service limit is usually around 130 i beleve. you might have a bad cylinder dude , warmed up or not. could be a bad rings , could be a valve slightly burnt. hard to say.

 

Your numbers are going to heavily depend on your altitude. As your altitude is higher, atmospheric pressure raises.

Atmospheric pressure <U>at sea level</U> is 14.7psi. Your CR, for example, is 10:1.

14.7 x 10 = 147 psi +/- 10% in each cyl is good.

LS/Vtec with stock pr4 pistons and a b16 head is somewhere around a 9.7:1 CR i believe.

So at sea level, 9.7x14.7 = 142.6 psi.


with your initial posting all cyl being
Cyl#1 175 psi
Cyl#2 170 psi
Cyl#3 180 psi
Cyl#4 170 psi

it looks like your good.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blackKready &raquo;</TD></TR><TR><TD CLASS="quote">service limit is usually around 130 i beleve. you might have a bad cylinder dude , warmed up or not. could be a bad rings , could be a valve slightly burnt. hard to say.</TD></TR></TABLE>

Thanks man, I know is hard to say from this point, but I'm checking the valve on monday, hope it isn't a bad cylinder problem because i'm broke at this moment

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Silver-RC &raquo;</TD></TR><TR><TD CLASS="quote">

Thanks man, I know is hard to say from this point, but I'm checking the valve on monday, hope it isn't a bad cylinder problem because i'm broke at this moment </TD></TR></TABLE>

There's also a trick where you pour a little oil into the cyl and re-check the compression. If it goes up a lot = bad rings, if it stays about the same = bad valves.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fdavie &raquo;</TD></TR><TR><TD CLASS="quote">

There's also a trick where you pour a little oil into the cyl and re-check the compression. If it goes up a lot = bad rings, if it stays about the same = bad valves.</TD></TR></TABLE>

Thanks for the tip man , I'll try it and post the results too.

cya

 

I'm looking at a 2005 Element w/ 2.4L V-Tec and the pressure readings are 190-195-190-175. I was wondering if the last reading was too low or means that the head gasket, rings or valves might be bad?

Mahalo Nui Loa,
aukaiiki sends...

 

aukaiiki, please create a new thread in the CR-V/Element forum -> https://honda-tech.com/forums/honda-cr-v-element-156/

I would say that last reading is a bit low though.