compression test
22-Apr-2008, 05:58 PM
#1
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compression test
whats up everyone,
this weekend im doing a compression test on my motor i have a
D16Z6 1590 125@6600 106@5200 9.2:1 75 90 sohc yes 1 1992-1995 Civic EX/Si/Del Sol Si
now i know my compression is 9.2:1 so does this mean im looking for around 170-190 psi in each cylinder???
Thanks in advance
this weekend im doing a compression test on my motor i have a
D16Z6 1590 125@6600 106@5200 9.2:1 75 90 sohc yes 1 1992-1995 Civic EX/Si/Del Sol Si
now i know my compression is 9.2:1 so does this mean im looking for around 170-190 psi in each cylinder???
Thanks in advance
22-Apr-2008, 06:33 PM
#2
yes that's about right. i'd be overly concerned if you were reading 150 and under. also, ea cyl is supposed to be like w/in 5% of the other cyls. good luck.
and I think 130 and under it won't run anymore
and I think 130 and under it won't run anymore
22-Apr-2008, 07:12 PM
#3
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ohh okk mint.. thanks man...
so what your saying is... if its a low reading.. this motor is gonna be toast soon lol
Once i do the test i will post results and you gentlemen can tell me what you think
05-Jul-2008, 03:00 AM
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just to clarify guys,
some ppl were telling me to take out the fuse for the fuel pump when im doing the compression test??
im not too sure if this matters or not cause ive never done this type of test before.
And does it matter how many cranks i should turn it over ?
some ppl were telling me to take out the fuse for the fuel pump when im doing the compression test??
im not too sure if this matters or not cause ive never done this type of test before.
And does it matter how many cranks i should turn it over ?
05-Jul-2008, 08:02 AM
#5
yes pull the fuse for the ECU/fuel pump in the under-hood fuse box.
Remove ALL spark plugs.
Let the engine crank over 6-7 times per cylinder.
The results should be within 10% of each other.
Remove ALL spark plugs.
Let the engine crank over 6-7 times per cylinder.
The results should be within 10% of each other.
05-Jul-2008, 08:37 AM
#6
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unplug the distributor, on eg's they have a fuel pump fuse.. on ek you pull the "FI ECM" fuse.
let the car warm up though before doing a compression test. When cranking the car hold the throttle to the floor and let it crank four times. The numbers should be within 5-10psi of each other.. anything above 15psi difference I would be concerned.
let the car warm up though before doing a compression test. When cranking the car hold the throttle to the floor and let it crank four times. The numbers should be within 5-10psi of each other.. anything above 15psi difference I would be concerned.
07-Jul-2008, 07:41 PM
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AHhhh
ok ok mint, thanks guys
i didnt know i had to take all the spark plugs out, i thought i only took out the one i was doing the test in, and leave the rest in?.
do it when its warm?, its aluminum wont the threads strip cause of the heat?? i thought you are supposed to do this when the engine is cold?
ok ok mint, thanks guys
i didnt know i had to take all the spark plugs out, i thought i only took out the one i was doing the test in, and leave the rest in?.
do it when its warm?, its aluminum wont the threads strip cause of the heat?? i thought you are supposed to do this when the engine is cold?
07-Jul-2008, 09:02 PM
#8
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#1 take all the spark plugs out, remove the fuel pump fuse
why? You want the engine to spin as freely as possible and you don't want fuel getting into your gauge.
#2 Why would the threads strip because of heat? If the spark plugs were installed correctly you won't strip the threads.
#3 You want the engine at operating temp since all the parts, etc will be expanded and at operating spec's.
IMO a leak down test would be a more reliable tell tale on the overall condition of your engine.
why? You want the engine to spin as freely as possible and you don't want fuel getting into your gauge.
#2 Why would the threads strip because of heat? If the spark plugs were installed correctly you won't strip the threads.
#3 You want the engine at operating temp since all the parts, etc will be expanded and at operating spec's.
IMO a leak down test would be a more reliable tell tale on the overall condition of your engine.
08-Jul-2008, 12:24 AM
#9
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well because its made of aluminum not cast iron, so when it heats up, and you try to take the spark plugs out you can strip the threads..
and yes i agree with the leak down test, but i want to first check to see if i am at adequate compression, and if i notice a loss then i will go into depth to find out whether or not its
my rings;
my exhaust valves;
or my intake valves
and yes i agree with the leak down test, but i want to first check to see if i am at adequate compression, and if i notice a loss then i will go into depth to find out whether or not its
my rings;
my exhaust valves;
or my intake valves
08-Jul-2008, 10:33 AM
#11
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ok ok
fair enough
i just wanted to make sure, but since everyone has not had a problem, then i guess its alright..
a little off topic here,
but what are your thoughts about gaping your spark plugs?
fair enough
i just wanted to make sure, but since everyone has not had a problem, then i guess its alright..
a little off topic here,
but what are your thoughts about gaping your spark plugs?
09-Jul-2008, 07:22 AM
#15
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Why would you want get rid of back pressure? The only I could see is to get to change the restriction. ie. exhaust system Unless your engine is heavily modded it will be a waste. $a few hundred $ for 3 hp @ 7,000rpm. pff not worth it.
What is the problem your facing if your engine?\
09-Jul-2008, 10:24 AM
#16
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well by heavily modded, im assuming you implying a turbo or supercharger right?..
Well my car runs mint, the ONLY thing that drives me crazy is.. i have a 2.5" exhaust, and a 3" magaflow muffler.. it sounds mint, nice deep bass, BUT if i rip it.. at the end i hear a little fart.. and it honestly drives me crazy.. thats why i wanna see if i can gap the spark plug, cause i have a feeling that maybe all the fuel is not igniting in the cylinders, and its igniting in my exhaust which is causing that sound..
Well my car runs mint, the ONLY thing that drives me crazy is.. i have a 2.5" exhaust, and a 3" magaflow muffler.. it sounds mint, nice deep bass, BUT if i rip it.. at the end i hear a little fart.. and it honestly drives me crazy.. thats why i wanna see if i can gap the spark plug, cause i have a feeling that maybe all the fuel is not igniting in the cylinders, and its igniting in my exhaust which is causing that sound..
