cold engine compression test vs hot engine compression test
#1
Honda-Tech Member
Thread Starter
cold engine compression test vs hot engine compression test
is there a difference in psi results. cause my car been sitting in the garage for 3 weeks and i did a compression test and it was average 60 psi. is that bad or does it vary with engine temp?
#2
Re: cold engine compression test vs hot engine compression test
You have to have the motor at running temp. Doing it on a cold motor is pointless since it doesn't tell you anything. 60psi would mean the motor was done if it was fully heated up. Drive for a few minutes til it's up to temp and do it again
#3
Honda-Tech Member
Thread Starter
Re: cold engine compression test vs hot engine compression test
because my car wont start, and i was doing it at a cold temp. so low compression would be low if its a cold engine?
#5
Honda-Tech Member
Join Date: Mar 2006
Location: Columbus, OH
Posts: 2,062
Likes: 0
Received 0 Likes
on
0 Posts
Re: cold engine compression test vs hot engine compression test
You will get different readings for warm and cold engines, but 60 psi is pretty low in either case.
Are you testing with an open throttle?
Are you testing with an open throttle?
Last edited by ddd4114; 07-13-2009 at 08:41 PM. Reason: spelling
#6
Honda-Tech Member
Thread Starter
#7
Honda-Tech Member
Join Date: Mar 2006
Location: Columbus, OH
Posts: 2,062
Likes: 0
Received 0 Likes
on
0 Posts
Trending Topics
#8
Honda-Tech Member
Re: cold engine compression test vs hot engine compression test
Compression test is done on a hot engine. This way all the parts expand on heat and keep a better compression.
#9
Re: cold engine compression test vs hot engine compression test
I understand that the compression test is better done with the engine hot but if your engine isn't starting how do you do that? I just did a test because I think my headgasket is blown. I'm getting 105psi in each cylinder and the minimum is 135. I would have thought at even at 105 it would at least start. Also, it seems odd that I have low compression in each cylinder. Any thoughts?
#10
Honda-Tech Member
Join Date: Mar 2006
Location: Columbus, OH
Posts: 2,062
Likes: 0
Received 0 Likes
on
0 Posts
Re: cold engine compression test vs hot engine compression test
If you ran the test with an open throttle, 105 psi is pretty low, even for a cold engine. However, it should still be able to start, even though it'll run like poop.
Sounds like trouble
Sounds like trouble
#11
Honda-Tech Member
Re: cold engine compression test vs hot engine compression test
Thread
Thread Starter
Forum
Replies
Last Post
r.etheridge
Honda Civic / Del Sol (1992 - 2000)
2
02-12-2011 05:31 PM
itsmebeaner1987
Honda CRX / EF Civic (1988 - 1991)
5
10-31-2004 11:54 AM
93, civic, cold, compression, compresson, difference, engine, honda, hot, low, performance, sohc, tech, test, versus