Compression Test Results
#1
Evolved Member
Thread Starter
iTrader: (7)
Join Date: May 2008
Location: VaBeach
Posts: 587
Likes: 0
Received 0 Likes
on
0 Posts
Compression Test Results
What are yours?
my 1 and 2 were 105psi
3 and 4 were 95psi
low or no?
recently had the dipstick blow out.... but the catch can was clogged
so, are these low or average?
my 1 and 2 were 105psi
3 and 4 were 95psi
low or no?
recently had the dipstick blow out.... but the catch can was clogged
so, are these low or average?
#5
Former Sponsor
iTrader: (1)
Join Date: Jul 2004
Location: Wood Dale, IL
Posts: 1,652
Likes: 0
Received 0 Likes
on
0 Posts
I have compression tested a few 4b11ts now. The readings seem to vary from cylinder to cylinder, motor to motor, and even test to test on the same cylinder. It has to be something to do with the mivec on both cams floating around with the lack of or low oil pressure/control.
A leakdown test will show you the true health of your motor and show any problems that you may have.
Basicly if the cranking compression sounds healthy, the car makes the power it should, doesn't smoke or make noise, then its probably fine.
If you don't know what a car sounds like when cranking with a dead or low cylinder, pull one plug out and crank it and thats what it will sound like.
A leakdown test will show you the true health of your motor and show any problems that you may have.
Basicly if the cranking compression sounds healthy, the car makes the power it should, doesn't smoke or make noise, then its probably fine.
If you don't know what a car sounds like when cranking with a dead or low cylinder, pull one plug out and crank it and thats what it will sound like.
#7
Evolved Member
Thread Starter
iTrader: (7)
Join Date: May 2008
Location: VaBeach
Posts: 587
Likes: 0
Received 0 Likes
on
0 Posts
I have compression tested a few 4b11ts now. The readings seem to vary from cylinder to cylinder, motor to motor, and even test to test on the same cylinder. It has to be something to do with the mivec on both cams floating around with the lack of or low oil pressure/control.
A leakdown test will show you the true health of your motor and show any problems that you may have.
Basicly if the cranking compression sounds healthy, the car makes the power it should, doesn't smoke or make noise, then its probably fine.
If you don't know what a car sounds like when cranking with a dead or low cylinder, pull one plug out and crank it and thats what it will sound like.
A leakdown test will show you the true health of your motor and show any problems that you may have.
Basicly if the cranking compression sounds healthy, the car makes the power it should, doesn't smoke or make noise, then its probably fine.
If you don't know what a car sounds like when cranking with a dead or low cylinder, pull one plug out and crank it and thats what it will sound like.
I will do a leake down this week.
Trending Topics
#9
Evolving Member
Join Date: Oct 2009
Location: SL, UT
Posts: 438
Likes: 0
Received 0 Likes
on
0 Posts
Well unless you're at altitude like me... I see roughly 125-130 psi on my healthy 4B11. Then again, it could be my compression tester adapter, but I've always seen lower compression results up here because of the significantly lower (~12.7-12.8 psi) atmospheric pressure.
#11
Evolving Member
Join Date: Apr 2009
Location: queens
Posts: 378
Likes: 0
Received 0 Likes
on
0 Posts
damn thats low brother! the good thing is they are not too far apart from each other. It's suppose to be like 10 percent. You should be around 145 and up...make sure you do the test after you got the engine hot ....
#12
Evolving Member
Join Date: Oct 2009
Location: SL, UT
Posts: 438
Likes: 0
Received 0 Likes
on
0 Posts
Hot vs. cold will make a ~5 psi difference at most on an engine with hypereutectic pistons like ours.
#13
Evolved Member
Thread Starter
iTrader: (7)
Join Date: May 2008
Location: VaBeach
Posts: 587
Likes: 0
Received 0 Likes
on
0 Posts
crossing fingers.
#14
Evolving Member
Join Date: Oct 2009
Location: SL, UT
Posts: 438
Likes: 0
Received 0 Likes
on
0 Posts
How many times did you let the engine turn over while you were testing it? I like to do at least 6-8 compression cycles to get a good reading, else it will read low.