compression test
#1
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compression test
Ok, I have the intercooler piping/elbow out. I removed the top two sprak pulg wires. Then I reached in and felt the plugs and wondered...what tool do I use to take these off? Any help appreciated
I am doing a compression test....
I am figuring i remove the top 2 plugs and then stick in the compression tester to where the plugs went and crank over engine...is this how it goes?
I cant start my engine but it is still getting air/fuel/spark...so is it still possible to test compression on just having it turn over as much as it can?
Do I need to remove any fuses while turning th engine over?
Thanks for the help guys...always appreciated! =)
Hope results come out good
I am doing a compression test....
I am figuring i remove the top 2 plugs and then stick in the compression tester to where the plugs went and crank over engine...is this how it goes?
I cant start my engine but it is still getting air/fuel/spark...so is it still possible to test compression on just having it turn over as much as it can?
Do I need to remove any fuses while turning th engine over?
Thanks for the help guys...always appreciated! =)
Hope results come out good
#2
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if you want to know your motor condition without going through all that, you can just check your boost guage.
During idle, your vacuum should be hitting above 450mm/cm^2. If below, most very likely you will be needing motor rebuilt due to low compression.
During idle, your vacuum should be hitting above 450mm/cm^2. If below, most very likely you will be needing motor rebuilt due to low compression.
#3
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there is a bunch of procedures to do. There should be a few threads about this.
off the top of my head......
unplug ONE spark plug at a time and use the top one.
take fuel/spark fuse out
press pedal all the way down
take check valve out of compression guage
watch for 3 even bounces
when cold the readings are inaccurate
off the top of my head......
unplug ONE spark plug at a time and use the top one.
take fuel/spark fuse out
press pedal all the way down
take check valve out of compression guage
watch for 3 even bounces
when cold the readings are inaccurate
#4
Rotary Freak
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Originally posted by ooEfiniRx7oo
During idle, your vacuum should be hitting above 450mm/cm^2. If below, most very likely you will be needing motor rebuilt due to low compression.
During idle, your vacuum should be hitting above 450mm/cm^2. If below, most very likely you will be needing motor rebuilt due to low compression.
#5
Tenseiga
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With a street port idle vac will go down.
I think there are too many variables to just check vac at idle.
compression checks are not that hard. I don't think it's worth 70 bucks or whatever to have the dealer tell me my car is fine.
I think there are too many variables to just check vac at idle.
compression checks are not that hard. I don't think it's worth 70 bucks or whatever to have the dealer tell me my car is fine.
#6
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As long as its running dont worry about it. You can pull one leading plug out and a time and pull the main efi fuse then just turn the engine over. Listed for all even bounces.
STEPHEN
STEPHEN
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compression is 5.2 kg/cm^2 on rear rotor and 12.5 kg/cm^2 on front rotor. Also equals 70 PSI on rear rotor and 185 PSI on front rotor. Looks like i am getting a rebuild.
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#8
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Originally posted by mr g lord focker
compression is 5.2 kg/cm^2 on rear rotor and 12.5 kg/cm^2 on front rotor. Also equals 70 PSI on rear rotor and 185 PSI on front rotor. Looks like i am getting a rebuild.
compression is 5.2 kg/cm^2 on rear rotor and 12.5 kg/cm^2 on front rotor. Also equals 70 PSI on rear rotor and 185 PSI on front rotor. Looks like i am getting a rebuild.
#9
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Using the right tool?
Rotaries require a special compression gauge. If you're using a piston gauge, it might explain the numbers you are getting.
Beast
Beast
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probably..but it atleast showed me what I needed to know. All for plugs were pulled and both readings on front rotor and back rotor were the same. But the rear rotor had only about 1/2 the reading of the front rotor BOTH times so I know I need rebuild....but thanks for letting me know about the #'s
#12
Tony Stewart Killer.
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when you have a suspicion that your motor is blown you dont need a guage to tell you anything. Just pull the fuel pump relay take out 1 of either plugs on each housing out and listen. Do one plug at a time then replace it and go on to the next housing. youll hear a pattern of the motor spinning over it needs to sound the same on all 3 beats or there is a problem
now to do a relative compression test to see what the condition of an old motor is a guage is needed
sorry about your motor
now to do a relative compression test to see what the condition of an old motor is a guage is needed
sorry about your motor
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