View Full Version : 5sfe Cylinder compression test

07-10-2008, 02:45 AM
Ok..soo i was out workin on the old mans dakota n had to do compression test on it soo figured while i had it out n was in the mood I'd do one on my car :bigthumbu 1990 5sfe 225,000kms...let the car warm up to op temp, pulled the plugs, efi fuse, hooked up the compression tester just ur average tester looks like this
cranked it over about 5-6 times each cylinder and got
1-220ish minus psi
2-215ish plus psi
3-215ish plus psi
4-215ish minus psi

Plus meanin a lil over minus meaning a lil under (Large needle not many #'s so not exact #'s but gives u an idea) did a quick search and to me those numbrs seem on the high side ? should be somewhere around 180ish no ? I could be wrong... Thoughts ? :wiggle:

07-10-2008, 03:50 AM
Looks fine to me, just means you cranked it a lot. Probably would read around 180ish with 4 cranks or so, but being that they're all close to the same number, that's a good thing.

07-10-2008, 04:14 AM
Picture broken. Doesn't matter, though, it obviously fit into the cylinders. :)

Results look good, there isn't nearly enough of a variance in the values to indicate any problems. Almost as close as the coupe's 3S-FE was at 215k.

Edit: Nevermind, the picture worked on reload.

07-10-2008, 07:43 PM
Thanks for the info, yeah i was happy with how close they were, just the high number caught me by surprise :)

07-15-2008, 10:38 PM
Ever think about doing a "Leak Down" test? It is another way to check for compression leaks.

07-15-2008, 10:42 PM
yeahh thought about it, but i wasnt really looking for a leak, i just had the tester out n figured why not haha, that was just the first time on that engine and the #'s seemed high..i just like to share ma info :)

07-16-2008, 01:15 AM
I guess the leak down test finds bad head gaskets or bad valve seats...

07-16-2008, 01:45 AM
I've never done a leakdown test before, what equipment do you need?

07-16-2008, 01:57 AM
Leak down tester and access to air ( air compressor )

07-16-2008, 02:13 AM
cant complain about 200, its still good compression. I want to do a cylinder leakage test on my celica, that'll show more than a compression test will

07-16-2008, 02:27 AM
Little on the high side, but the variance is good:

Compression pressure:
5SFE 1,226 kPa (12.5 kgf/cm2, 178 psi)
or more

Minimum pressure:
4AFE and 5SFE
981 kPa (10.0 kgf /cm2, 142 psi )

Difference between each cylinder:
98 kPa (1.0 kgf/cm2, 14 psi) or less

07-16-2008, 02:49 AM
yeahh same here ill see if someone i know has a leak tester n get on that at some point....

Thanks Galcobar your on the ball haha always good for nice short simple responses and good answers

07-16-2008, 05:55 AM
actually while Im thinkin about this, there are some tips you should know about leakdown tests. First, you gotta have TDC as Im sure you know, but often when you put air it rotates the motor. How do you fix this? If its a manual tranny, put it in say 3rd gear and simply pull the car (with a buddy) and it'll make the motor move. If you have an auto, however, you can use a pully with a nice solid (in other words, big) nut on it to rotate the motor, but only do it in the direction the motor opperates. Just to save anyone some frustration in case they try it. If you perform a leakdown, you can also tell which valves its leaking from by listening to the intake side, or exhaust side, or you can take off the oil filler cap and see if its leaking past the rings or maybe a cracked block.

07-16-2008, 06:02 AM
Leakdown test is a much better test. It lets you see if you have bad rings or bad valve seats or hg. With a compression test it's tough to get the whole picture. Carbon build up will alter the results as well as how good your battery is and how many times you crank it.