How To Do A Compression Test (Scion TC/XA/XB)

[MegaMarshal]

Awesome your hot and, smart which can be rare lol.

The only 2 things i noticed you left out was: you should hookup a battery charger and, also dip the end of the tester in some engine oil. Its not the most important tho. Im suprised you informed us of depressing the gas pedel. Most other vids leave that out.

[toprepublic]

great instructions thanks! could have been a bit shorter though!

[chivoAmuerte]

u dont need a wood board- just disable spark!

[blueturbotc]

This guy is a moron, take the EFI fuse out its easier and faster (def if you have a strut bar), EFI stands for Electronic Fuel Injection! has nothing to do with the coil packs, Pull your IGN fuse and or Just un plug your coil packs, He says to do it 4-5 times but he cranks its 7?, Also admits on his first test (just earlier that day) he did it 10-15 times! He should not be showing anyone how to do this. Dont listen to this guy please! Video is only good for knowing what tools you need.

[chivoAmuerte]

@blueturbotc ur right!

[DALE97DSM]

Nice car and very good readings that is stock compression by the way. Also, low readings is bent valves too, besides what you said. 

[guyana104plyr]

hey,. i was wondering what turbo u have installed, and did u have to chip the ECU.

[angrut]

Hey thanks for this video bro!! Now I can do my compression test very easy. But I thought the higher the compression the better.

[muzairanwar]

awsome video man... thanks for that...

[Vucijak86]

YOU HAVE GAY VOICE

[monkeyhmong87]

oh man this guy running turbo. nice

[Lovestani]

awesome detailed video thanks for uploading and making it

[JorgeAlejandro1970]

very good and helpfull video, thanks guy

[pits200]

Eh, nice vid but not exactly right about the same amount of cranks for each cylinder. The pressure will only reach a maximum no matter how many cranks.

[titytots17]

great DIY

[notoriousleb]

Nice vid

[EndlessT]

nice video

[gcamelo82]

it was very helpfully thanks...

[CHARrrrrrrrr]

why didnt u just unplug ur coilpacks?

[bathieutu]

@CHARrrrrrrrr

It is the coil on plugs type. so u have to remove the coil.

[dosteddaram]

thanx for the great job

[behellit]

I was actually searching on how to do this test I really appreciate, thank you

[EthanTheExplorer]

Great video but...... AutoZone, WALMART or any other RACE shop. LMAO

[BudgetPhoenix]

@EthanTheExplorer

he said any general race shop. Not other like he was implying autozone or walmart were race shops

[zacferrer]

very educational ...keep it up!!!

[tcschweitzer]

Maybe this is my lack of understanding but why wouldn't you just disconnect the coilpacks?

[SPAGHETTIMONSTER1]

pretty good.

[Triple88a]

charging the coils over and over but not letting them discharge is bad. To a lot/most cars it can permanently destroy coil packs.

[wyatt153]

Great video but how would you crank the car if it was automatic?

[mitmaks]

You would put your car into neutral and press gas pedal all the way in when cranking.

[SPAGHETTIMONSTER1]

turn the key, ha ha. same on any car

[TrojanHorseXX]

Good video, next step will be a cyclinder leage test. that will tell you where the leakage is coming from. you really have to do this if you want you compression was low.

[mrkevindshore]

@ 3:52 that is the head.... not the block....

@ 6:35 the EFI fuse is electronic fuel injection....

@ 8:28 you tried and failed twice.... you need both hands lol

@ 9:30 i wrap them in shop towls

@ 10:00 that jolt is 1.21 jigga watts.... GREAT SCOTT

@ 10:30 i like your deck

@11:10 ....4 or 5, 7, 6 or 4 or 5 turns.... amke up your mind lol

good DIY tho

[viper2788]

thnx for the input... it was necessary.

[javier918]

I have a Question... How do you know what is the correct pressure depending of the "compression ratio"?.. for example a motorcycle.. bicylinder 650cm3 and a compression ratio of 11,5 :1.. how many psi do I need to check in the barometrer ? thank you so much and excuse me for my bad english :D

[Peachis007]

Thank you for your video. It gave me all the information needed to do my first compression test successfully.

[hokman1]

very good video Thank you.  My cousin in LA has a TC too.

[okojo2025]

英語めんで～

説明ど～でもいいしぃ～

[mailid1212]

what diffrence does it make on how many time you crank?,as per my understanding on ever crank the intake and exhaust valve opens and closes, hence it should be the same presure or similar pressure build up on every crank rather then pressure get adding up on every crank.

i might have answer for my quesstion but correct me if iam wrong (is that becaue of the limitation of the guage tot self store the presure on every crank and builds up rather then releasing it,hence adding up?)

[jgizzy]

That's what I assumed as well. That you don't really have to count cranks in order to get a proper reading, that the pressure should just naturally peak out based on how well the chamber seals.

[TrojanHorseXX]

It doesn't matter how many times you crank it. you want to have a min of 6 cranks for all the cyclinders. over crank will have a higher number and wrong output. equal crank should be done.

[nickswimsfast]

very useful video; not just for scion tc's but compression testing in general. Thanks!

[sayjdm]

nice video! very informative

[saintEmory]

AWESOME WORK!!

[PERZN4LIFE]

i took out my MPI (MultiPort Injection) fuse on the positive terminal of my battery. That was easier for me.

[newcomer9747]

i just bought a pressure gauge up to 230psi to make my own compression gauge. where is the schrader valve located in your compression gauge?

[drewce123]

What does it mean when ur car has low or high copression can som1 explain this? thx

[DvDizaster]

think of your motor as an air compressor.

the motor sucks in air and squirts a specific amount of fuel onto the head of the piston and when the piston comes back up it compresses and then the spark from your spark plug sparks and the mixture explodes.

if your car has low compression, that means your pistons are wearing down or have work down and this can lead to engine failure

im sure some else here can explain it better then i can. i'm not a engineer or anything

[drewce123]

ohh ok i understand what u mean thanks

[PERZN4LIFE]

Possible causes for a low compression condition are burned intake or exhaust valve, broken piston or piston ring, broken valve spring or a blown head gasket.

ohhh btw

Be aware that a cylinder suffering from excessive oiling, even from bad rings, can yield high compression test results because the excess oil in the cylinder seals the rings.

hope that helps but if you need me to send you on how to Interpret the readings, then send me an message =)

[drewce123]

lmao i think i understand what you mean are these all the possibility's with low or high compressions or is there more to it than just head gasket,broken piston,broken valve spring ext,?

thanks for the reply btw.

[salloroc20]

FYI KPA is not "K PSI" it stands for Kilo Pascals. metric measurement of pressure

[david04]

great vid man. very useful

[WTFp0s]

My 93 hatch has a Comp of 200 - 210

[slowanlow]

hahah, what the pieice of wood really nessary from the coil pack...why not disconnect the coil?

[Mordaan]

hey you need some else to watch how the pressure builds up.

low compression on the first stroke, followed by gradually increasing pressure on successive strokes, indicates worn piston rings.

[cyrmanj]

Thx 4 the vid! It is also important to take into consideration the test altitude compensation factor: Multiply the reading you get with the factor based on the altitude.

Altitude (feet) Factor

500 0.987

1500 0.960

2500 0.933

3500 0.907

4500 0.880

5500 0.853

[kharn83]

thanks dvdizaster

that was a great vid which explaned everything i need to know now haha

also it was gd u explained potential dangers like the coil packs etc which isnt always mentioned

cheers

[timanonymous]

Anyone know why you have to press the gas in while cranking?

Thanks for making the video. I didn't know how to do a compression test before, but now I do!

[DvDizaster]

Pressing The Gas is necessary because you have to have the throttle body fully open, the only that opens the throttle body all the way is the gas pedal.

if you don't press the gas pedal all the way down during cranking you'll get very inaccurate results.

[PERZN4LIFE]

you take a screw driver and put it manually on the throttle body to fully open it.

[cwtrain]

Why is this being down voted?

He's correct. You keep the throttle body open so you can get as much air as possible into the cylinders when you're cranking then engine.

[PERZN4LIFE]

i know...lol

[distortia47]

@DvDizaster or you can just prop the throttle all the way open with a screw driver...

[ThatZkid]

@distortia47 Well it's drive-by-wire so the only way to do that would be to actually shove a screwdriver down into your throttle body, which I think we can both agree is a bad idea

[leoghanta2002]

THATS WHAT SHE SAIDD!!!

[LTF85199]

thanks man well explained, i think it is going to be very useful. V

[petermanidds]

great video!

[123ma321]

you're so brillian dude!!!

[infamouskillas]

wtf?

[CSOCSO]

thx for the vid

[onekingdwnjh150]

Why did you not just disconnect the coil packs???

[philProjectD]

Good video man, I enjoyed it. :)

[philProjectD]

Good video man, I enjoyed it. :)

[colocho19]

Nice work, but the EFI fuse is so much better, easier and faster.