R32 Gtr No Spark To Spark Plug Need Help!

[XKLABA]

So you tested the spark at the plug yeah and no spark, was that with a new plug or the plug out of the cylinder covered in fuel

If an injector is locked open it will give similar results and foul the plug, if there is no spark with a new or known working plug then it's electrical, so if you have changed plugs - coils - loom - ECU, then what's left, would have to CAS

[Colejr]

I swopped over injectors, no difference just the one cylinder has no spark, can I hard wire the coil pack with a relay and try that?

[Colejr]

I swopped over injectors, no difference just the one cylinder has no spark, can I hard wire the coil pack with a relay and try that?

[Colejr]

How do I test the cas?

[GTSBoy]

Swaptronics usually.

[Colejr]

My you saying swop for known working one? It's not that easy to get gtr parts here in canada, people are dic#s about skylines and hrs cars here do not much available

[GTSBoy]

Yup, and there is precious little else that will tell you whether your CAS is working properly or not.

Just buy one from and Australian source and get it sent to you. Even if it turns out you don't need it, a spare on the shelf is no bad thing.

[Colejr]

Ok thanks, I did a compression test awhile ago and numbers were good, but noticed the previous owner over filled the motor with oil and I drained some of it out and did a test again today and numbers did not look too good, I called it a day and I'm going to do another test tomorrow and see what that shows, I will do a compression test before and after I drop a cap of oil in the cylinder.

[XKLABA]

An oscilloscope can tell you if the CAS is not working right

What was the result from the last comp test, 6 had no or very little comp ?

[GTSBoy]

An oscilloscope can tell you if the CAS is not working right

Yeah. I'm so tempted to go buy one of those 5 or 10 MHz Velleman handheld oscilloscopes for just that sort of investigation. Also good for looking at speed senders and stuff like that too.

[XKLABA]

I bought one to find a signal issue in the new motor then found out the ECU I have has one built in, bonus, so I took it back

[Bick033]

Get a LED test light and test what signals you have at the plug on the coil. You should have an ignition positive a ground and a pulse that is also ground on the externally igniter coils. Smart coils will have a positive pulse. Hope that is some help it's a very cheep and handy tool to have

[Colejr]

Xklaba, the last compression test had shown that there was 135-140psi between all cylinders, but when I did that compression test it was really cold still I'm not sure if the cold would have effected the results by thickening the oil, bick033 I got a regular test light would that be fine? An oscilloscope is that just another word for timing light?

[Colejr]

So I did a compression test and I got values starting from the firewall back, 105/140 after a cap of oil, 130, 150, 150, 145, 140. I didn't waste time putting a cap of oil in the cylinder that's at 130, or the rest of them

[XKLABA]

An oscilloscope reads the voltage signal wave and displays it on a sceen so you can see it to see what is getting sent to the ECU, completely different to a timing light

130 is low but not enough to kill the cylinder altogether, 140 is on its way to be low, 145 is exceptable, 150 is your norm with the tester your using, so you didn't put oil in any of the cylinders yeah ? What did you mean by 105/140 ?

[Colejr]

It was 105 without oil and 140 with a cap of oil

[Bick033]

With a normal test light it is hard to see a pulse because the filament takes time to fully go out so it will just look like it's on all the time it will be fine to use it will just look like a ground all the time when running.

[Colejr]

Bick033 ok I'm going into town tomorrow and I will get one, I couldn't really put much time into the car today as that's all I've been working on all week, and this is my last few days off work and I will be gone away for awhile so I had to do some work around the acreage. I put the plug up agains the breather and couldn't see a spark, but I will go buy the oscilloscope tomorrow and try it

[Colejr]

I'll get that led test light tomorrow aswell

[GTSBoy]

Bick033 ok I'm going into town tomorrow and I will get one, I couldn't really put much time into the car today as that's all I've been working on all week, and this is my last few days off work and I will be gone away for awhile so I had to do some work around the acreage. I put the plug up agains the breather and couldn't see a spark, but I will go buy the oscilloscope tomorrow and try it

Be aware that we're talking about a couple hundred $$ worth of oscilloscope here. And a reasonable amount of assumed knowledge to be able to use it. They're not going to help the uninformed/inexperienced. Definitely a techie's toy.

Edited April 11, 2014 by GTSBoy