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Old 03-20-2010, 05:28 PM   #1
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Default compression testing

i've tried looking it up a few places and some suggest slight variations like not unplugging the injectors and **** like that so... my guess goes something like this:

1 -start and bring car to temp then turn off
2 -unplug injectors
3 -unplug spark plug wires
4 -remove spark plugs
5 -plug in compression checker
6 -turn car 6 or so times with gas fully pressed
7 -repeat steps 5-6 for each spark plug hole
8 -hit crack pipe


am i missing something with the intake or is that a good list?
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Old 03-20-2010, 06:49 PM   #2
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Thats pretty good. As general rule 5-6 turns will do it, but really I just watch the guage and see when the needle stop rising significantly. I just unhook the injectors and the plugs too.
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Old 03-20-2010, 06:55 PM   #3
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sounds like a plan. that last one makes sense too
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Old 03-20-2010, 08:29 PM   #4
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Or you can just take out the fuel pump fuse under the hood would be alot easier.
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Old 03-20-2010, 10:16 PM   #5
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all in between 175-180. i'll take it.
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Old 03-20-2010, 10:25 PM   #6
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within 10% variation - good
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Old 03-21-2010, 01:03 PM   #7
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its really close to around 3%, that can't be bad.
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Old 03-21-2010, 01:42 PM   #8
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I thought I heard something about burning out the coilpack if no injectors were connected, but maybe I'm wrong, note am talking about 1.6l, dunno your car off hand.
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Old 03-21-2010, 02:25 PM   #9
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the only thing i read was progressively unplugging them resulted in a burn out, so it only distributes load over 3 then 2 then 1 coils when it is designed for 4 at once. when none of them are connected, the coilpack isn't making a circuit (i think,) and so it can't be burnt out. feel free to correct me, this is all speculation.

does anything bad happen to run a test with the injectors enabled?

fyi, i turned the car over quite a few more times than 24 (6 per plug) i tested each hole about 3-4 times with the injectors unplugged. and i didn't burn out my coil pack, knock-on-wood.

Last edited by frostyllama; 03-21-2010 at 02:41 PM.
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Old 03-21-2010, 03:16 PM   #10
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Quote:
Originally Posted by 18psi View Post
sounds like a plan. that last one makes sense too
you have NO idea. pollock pines= meth capitol of california... and yes, i have a lot of energy if thats what you're getting at lol.
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Old 03-21-2010, 04:58 PM   #11
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Seems like pulling the injector and the ignition fuses would do the trick. 30a and 60a on my car.
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Old 03-21-2010, 05:23 PM   #12
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I'd also add unplug your coil pack if your using an OEM part. I've heard that they can burn up pretty easily when doing a compression test without being grounded.

I'd also add like some others have stated about the fuel. Some ECU's have a flood clear section. On mine if the TPS sensor reads 85% it will not send any fuel past the injectors. Maybe easier than trying to find and pull a fuse.
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Old 03-21-2010, 06:41 PM   #13
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yeah, might as well disable them. i can see how bad grounding could adversely affect them.
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