Compression Test Question

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So i am going to do that this weekend. I was told what to do so it sounds fairly easy, can someone give me a step by step directions on how to do it so i dont mess up, the car doesnt need to be in any worse shape than it is.

questions;

1. can someone crank the key?
2. do i have to disconnect fuel injectors?

thanks
 

SHOZ123

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If you leave the key off and turn the motor over by hot wiring the starter relay then the FIs will not turn on.

Hot wire the starter

Starter hot wire
 
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so will the engine crank automatically when i hook that wire up, or do i hit something else after the wirs is hooked up to actually crank it?
 

SHOZ123

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Yes it will crank. I plug the end into the relay slot then use the clip in the end to bump the starter.
 
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i know this may sound dumb, but do i leave the battery hooked up i am only asking because of playing with the coils and i usually disconnect the battery whenever i do work under the hood as im not one who is too fond of electrocution
 

SHOZ123

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With the key in off the coils are dead. And without the battery connected it will be a bit hard to turn it over.......
 

bacernate

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You need to hold the throttle plates completely open to get an accurate test done. Also this will put the injectors in clear flood mode so the cylinders wont get washed down.
 

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