Very Low compression numbers
#11
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I believe the car is fine. No smoke from exhaust on startup or WOT, Neck and Neck with my friends s2000 and the mechanic gave me the go ahead.. I also changed the oil and so far the oil level hasnt moved.
After searching for hours i found another guy on the boards who had almost identical numbers as mine. He had his test redone and the numbers came out perfect so i took my chances and bought the car.
After searching for hours i found another guy on the boards who had almost identical numbers as mine. He had his test redone and the numbers came out perfect so i took my chances and bought the car.
#13
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there's tons of variation on compression check
some people would do a max compression check, meaning they crank the motor as much time as needed to get the highest number.
some people would do a set number check, meaning they only crank it for a set amount of time(usually 7 for me) for all the cylinder.
there's no right or wrong way, the second way is actually preferred for a rotary long story short.
on course you can have a gauge that reads low(like mine), hot vs cold motor, fresh battery, plugs out or not, etc
it varies but as long as it's done by someone that knows how to do it, there's nothing to worry about.
if you lose half of the compression, ecm should trigger hell and you'll know it.
some people would do a max compression check, meaning they crank the motor as much time as needed to get the highest number.
some people would do a set number check, meaning they only crank it for a set amount of time(usually 7 for me) for all the cylinder.
there's no right or wrong way, the second way is actually preferred for a rotary long story short.
on course you can have a gauge that reads low(like mine), hot vs cold motor, fresh battery, plugs out or not, etc
it varies but as long as it's done by someone that knows how to do it, there's nothing to worry about.
if you lose half of the compression, ecm should trigger hell and you'll know it.
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#15
my compression #'s were around 150ish and that's because it was done on a cold engine and it was at crank (start-up). so long as they're all around the same range and not too low.
#16
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what is your fascination with him hitting the gas pedal for a compression test?
#17
I would use another compression tester on a warm engine and see what you get...
Numbers that low across the whole engine point to the method of which it was tested or a faulty compression tester.
My .02
Numbers that low across the whole engine point to the method of which it was tested or a faulty compression tester.
My .02
#19
If your #'s were really 100psi in each cyl. the car would be slow as shit...
get an Actron gauge ($35) from Autozone & retest yourself, let the engine warm up fully, and make sure gas pedal is to the floor. Let it crank 8-10 times on each cylinder.
get an Actron gauge ($35) from Autozone & retest yourself, let the engine warm up fully, and make sure gas pedal is to the floor. Let it crank 8-10 times on each cylinder.
#20
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Originally Posted by datdude1119' timestamp='1301653352' post='20418906
I was wondering if there is a possibly the technician didnt hit the gas pedal while doing the compression test or something like that?
Was told the correct way to do the test is to go WOT with the fuel pump fuse pulled and with it warmed up to operating temperature?