im thinking to do compression test tomorrow on my spare time.

i just wondering do i have to pull any plug out to stop the injectors from dumping fuel while i put the car on WOT ?

and what sort of compression should be getting from a JDM ITR engine ? 11.2:1 CR i believe , 96-spec , done 130,000km

thanks guys

 

just pull the ecu fuse...if you don't you might have a nice 130 bill for a new ignitor w00t!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .D2 &raquo;</TD></TR><TR><TD CLASS="quote">just pull the ecu fuse...if you don't you might have a nice 130 bill for a new ignitor w00t!</TD></TR></TABLE>

Yep stupid me made that mistake with my last teg...there was almighty pop like a back fire and ignitor was toast

 

you should be around 240-270 in all cylinders for the JDm motor. I hit 270-275 no problem.

 

how many times do you have to crank it though ???

 

I just did this on the race turd yesterday (90 Civic, took a dump in cylinder 4 at Mid Ohio it looks like)... Anyway, you just crank it until the needle on the compression gauge stop rising. At least, that's what I was told to do

I was also told to pull the blue and black/yellow wire connector on the distributor before cranking it over as well, would this work on our ITRs too? I haven't even looked yet.

 

The process I use is this:

Pull all spark plugs (lowers the work load on the starter since no cylinder builds compression except the one being tested)
Pull the ECU fuse in the engine bay box (kills ignition and fuel)
Drop your comp tester in
Get in car and hit gas pedal to WOT
Crank away, usually takes 5+ to get a good reading.

 

I understand all but the "be at WOT" when performing the test, Can someone explain?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AK1200 &raquo;</TD></TR><TR><TD CLASS="quote">WOT</TD></TR></TABLE>

wide open throttle = pedal all the way down to the floor

 

What fuse reading does the ECU fuse have? For exmaple 15a, 20a... would it be hard to locate? Or is it one of those huge fuses? i am wanting to do a compression test on a car before i purchase it today. So basically what fuse should i be looking for? Im not too familiar with an eg but im assuming that the fuse cover should tell me that right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 &raquo;</TD></TR><TR><TD CLASS="quote">

wide open throttle = pedal all the way down to the floor</TD></TR></TABLE>


I know what WOT is, I was wondering why you needed to be at WOT to do the test?

 

you won't get true readings w/ throttle closed because hardly any air is getting into the chamber. at least thats my theory, my #s are way lower when testing w/ throttle closed.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .D2 &raquo;</TD></TR><TR><TD CLASS="quote">you won't get true readings w/ throttle closed because hardly any air is getting into the chamber. at least thats my theory, my #s are way lower when testing w/ throttle closed.</TD></TR></TABLE>

Yes, that is true...you must be at WOT during compression testing. No more than 5 cranks of the engine is the usual amount.

Must be at WOT to ensure proper cylinder fill.