Hi Everyone Today i did compression test on my motor which has 70k miles 2005 Ap2
My results were cylinder 1 from the front and so on
150
170
170
180
This is the way i tested I took all spark plus out and then put tester in to each cylinder and try to start motor for 10 sec on each cylinder
and that’s what i got.
I have read factory specification and it’s supposed to be 220+ up to 250 if I’m not wrong
So what’s going on, My car does not make any smoke or anything like that. I do smell some oil when I hit vteck but it does not burn anything because I checked dip stick 5 times after I changed my oil and I don’t see any smoke when I hit Vteck,

About 3-4 months ago I did use 110 octane only about 3 gallons or so I don’t know if that’s going to tell you anything.

There are no leaks of any kind (oil)
Please help me with this I don’t know what to do.
Also I did use cheap compression tester from harbor freight.

Also I notice that before you hit 3k you can feel car pull harder, not anymore its all smooth, so it seems like it lost lilbit of power already because i dont feel that pull anymore.

I over revved few times just stepped on gas and it went into redline for like split sec not misshifting or anything like that.

 

Was the car COLD or warm? Was the lowest compression the first one tested?

 

The car was warmed up I just pulled up to the shop and tested in 15 min after I took sparks out,
When tested first cylinder was 150, I retested and it was same.

 

Did you pull the fuel pump fuse? Battery fully charged?

As far as your slugishness did you inspect the plugs while they were removed?

The over rev that kills (mostly ap1) motors is when you down shift into the wrong gear and release the clutch forcing the engine to spin over the redline. You can hold it on the rev limiter for a few seconds and you're pretty safe.


Look up wet compression test. If you're still confident you have low compression you'll have to do a leak down test to check for blow by.

 

Yes

 

after i tested piston 4 i went back to 1 and it was even lower then 150

 

Numbers are really low but most are close together except for the 1 is a bit out of range. Over 15% difference between 1 and 4.

Original owner? As mentioned above a cold compression test will yield lower numbers. Different testers can read higher or lower numbers as well.


Do a wet test and see what they go up to. Just put a cap full of oil into each cylinder one at a time. And then repeat the compression test. It will seal rings if they are leaking during a dry compression test.

 

I didnt pull the fuse out,
Battery is 3 days old, Spark plugs were clean and white, like from store, (they were replaced about 1 k mile ) NGK platnum

 

You gotta pull the fuel pump fuse out when doing it and hold the gas pedal down wot. If you don't pull the plug then you will flood it with gas. S just pull it out and try again. I only remove 1 spark plug at a time. Not sure if it matters though. Make sure you do it on a warm engine, fuel pump fuse removed, make sure the battery is cranking hard, if not hook it up to jumper cables from another car running to make sure it cranks well.

If still a variance try the wet compression test method.

 

I think im 3rd Owner I got the car from action in 2012 theft recovery car had 66k miles under vin ( no gauage cluster) so i checked vin # and someone did service at dealer and dealer register 66k miles
How was it cold compression test if i had 8 bars on cluster and car was running for about 30 min before i removed plugs.