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Discussion Starter · #1 ·
I did a compression check today and figured i might as well do step by step pics while at it to help those who havent had a chance to do it or dont feel comfortable about it yet.

Results are:

1-149 psi
2-135 psi (first one was 119, then got around 125 3rd was 135)
3-149 psi
4-151 psi
5-150 psi
6-170 psi ( :dunno: i did this a couple times and still got 170)

For #2 first one was 119 so i figured i didnt tighten the gauge tight enough so i tried again and again and got the best of 135. I dont know why that one is the lowest, isnt usually the 4-5 are the lowest? My car doesnt smoke at all, it set for a couple days, started right up and no smoke at all... and there is no smoke at 5,000k when i asked my dad to rev it up so i can see, nothing! I also drove for about 6 hours from LA to sacramento and it didnt eat any oil what so ever. So i doupt that it has bad rings in #2 and i double that the seals in #2 are bad, so maybe i just didnt get the gauge in tight enough or who knows!!

for #6 beats me! i dont know how i got 170, i even did it a few times to make sure i wasnt seeing things, the stock is like 160... but i guess that 170 is what gonna give me that low 13 sec 1/4 haha, jk!

My car has 113k so what you guys say on the compression results?



Here is the step by step:

start the engine and run it for about 15 minutes or so and let it warm up, then turn the car off and pull the cover off.



disconnect solenoid resistor sensor connector



These little thing that hold the coil cables in place are pointless, if you never replaced them before they will just fall apart into little pieces when you are taking them off, kinda like a cracker haha, so make sure you clean all the pieces out before you take off the spark plugs so none of the pieces fall into the cylinder, wont be good! (im just not even gonne get the new ones, maybe later when im gonna gap the plugs



disconnect the coil connectors from the coils otherwise it will be a pain to pull them out.



unscrew the coils and make sue you get all the screws out and none get dropped where the sparks are



shake them around while pulling and they should yank right out.



now loosen the plus, and use 2 hands, i was just doing that for the pic, one hand is how you break them :)



i used little pointy pliers to pull the plugs out cuz my fatty fingers couldnt fit in there to reach



make sure you keep the coils in the same place they were in the car, dont want to mix them up. the plugs are worn and i need new ones.



tighten the compression gauge in there and then crank the engine over and hold it for about 10-15 seconds or so.



and here is the result on the first cylinder.



then pull it out and go to the next one.
 

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WI-FI FTW, GTFO fuse box!
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looks like #2 is bad(sorry!)
#6 looks to have carbon build up or something of the sort
-jt
 

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WI-FI FTW, GTFO fuse box!
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btw, i would be careful using needle-nose on the plugs, one mishap on the king-fu grip and you will drop them and break the electrode! :eek:hnoes:

(whh does the "ohnoes" smiley not work properly!!)
-jt
 

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Shawn Davis
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1. That's a nice write-up, I'm sure some people will appreciate it.
2. Do yourself a favor and never unscrew the coilpacks, remove the hex head bolts holding the pair of coilpacks in and remove them as a pair (much less likely to strip the hex than the phillips.)
3. Get a decent spark plug socket so that you don't have to use your fingers or the needle nose pliers to remove the plug.
4. You should have the throttle plate open when doing a compression test.

On to the results. I would suggest you repeat the test and add a teaspoon of oil to #2 to see if that improves the result. If it does you either have ring or cylinder wall problems. My guess is that what you're seeing is incomplete sealing of the valves due to carbon build up. I'd probably do an "Italian Tune-Up" and then repeat this test or if you really want to be sure do a leakdown test. That way you'll know where the problem lies.
 
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Nick, I find that funny. When I did my leakdown test and yielded some pretty shitty results on my 167K mile TT, my 6th cylinder was in the best shape of them all. :)

Those numbers obviously aren't what you'd desire. But I guess it all depends on what you want out of your vehicle. I'm fine with my numbers, since my car just looks nice and gets me where I wanna go.
 

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yeah i am like why did he unscrew the coil packs one by one. If you use the hex bolts they come out by 2s.(less work)
 

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Discussion Starter · #7 ·
Mad TKD said:
yeah i am like why did he unscrew the coil packs one by one. If you use the hex bolts they come out by 2s.(less work)
sorry my first supra!! :rolleyes:

next time will do a pair just for you guys hehe!!
 

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Discussion Starter · #8 ·
jt granberry said:
btw, i would be careful using needle-nose on the plugs, one mishap on the king-fu grip and you will drop them and break the electrode! :eek:hnoes:

(whh does the "ohnoes" smiley not work properly!!)
-jt
well i usually dont worry about the spark plus if im replacing them... so its no biggy, but i never in my life dropped a spark plug with my needle-nose skills!! :)
 

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Yea, definitely get a spark plug(3/8 i think) socket. otherwise great write up.

any recommandations as to what brand compression gauge to use? and when you said crank the engie for 10-15 seconds, you crank it only and not start it right? hwo do you go about doing this? pulling a fuse? Thanks
 

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Did you drive around and fully warm up the car prior to the test?
 

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Hardtopper
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Im assuming so, you can see in the first pic that the car is running/cams are turning
 

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Haha, I did the same thing the first couple times.
 

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Discussion Starter · #14 ·
PsyKotiC RydeR said:
Yea, definitely get a spark plug(3/8 i think) socket. otherwise great write up.

any recommandations as to what brand compression gauge to use? and when you said crank the engie for 10-15 seconds, you crank it only and not start it right? hwo do you go about doing this? pulling a fuse? Thanks
i have been doing it the old way for years, plus honestly i dont like spending money on things i can work around, sometimes it costs me if i make a mistake, but in the long run i save tons of money working around little things that cost :)

The compression gauges i borrowed from a friend so i dont know if the brand actually makes any difference... and i cranked the engine for 10-15 seconds and no it doesnt start, since i pulled all the plugs out and disconnected the solenoid resistor sensor connector in the second picture. so you dont have to worry about anything when you turn your engine over.


Ascari_2 said:
Did you drive around and fully warm up the car prior to the test?
no i let it idle for about 15 minutes and before i turned it off i reved it to 2,000k for a few minutes to let the needle rise to about 3/4


VR4_007 said:
Im assuming so, you can see in the first pic that the car is running/cams are turning
by the way i didnt take off the valve cover while the engine was running, i first took off the cover then i started the engine and kinda put the cover next to the valve cover to make it look like i just took it off, but dont take off the cover while engine is running... not a good idea, little dangerous.
 

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Make sure to drive the car.
 
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