Need some spark plug reading help

[Toby_Goodmk]

Take a look at the pictures. It seems I have #6 not completing combustion. I was wanting someone to help me diagnose if this is a fuel issue, or a spark issue. It appears there is some carbon of some sort on the porcelain which makes me think the plug is arcing. The others are suspect as well as they are a little wet on the threads, however this may be due to me not driving much and most of the reading on these plugs are from idling.

My condition that brought this about was a miss and low power through mid throttle.

**#6 cylinder is the clean one.
**#3 plug is burning, so it tells me because of waste spark that coil seems to be operating ok???


Any means to testing and making sure?


These are 60lb Precision siemens, with the TR6 module

 

[BEATAV8]

Looks like its not firing on that one at all. Say you feel a miss? Wire would be my first suspect.

 

[Toby_Goodmk]

Took everything apart to take a look, and I am a little baffled

This #6 injector was not operating at all. I could tell by the marks that the O rings left on my new powder coated intake, all 5 others had a stain, this one....nadda.

I took the rail and the injectors off. Took the suspected injector and tested ohms, 12...so that is ok

Took the injector and put voltage to it....click,click...so its opening and closing.

Took the wiring harness and checked continuity....beep beep....so the wiring is ok.

Took the open end of the wiring harness and left the injector hooked to the rail at the other end of the harness..applied voltage....click click, so the connections are ok.

So this eliminated any electrical connection issues up to the injector harness connector.

I took brake clean and the syringe with vacuum line, to voltage trick, it sprayed a pattern....so Hell if I know!!

Driver from the ecm????

 

[BobbyBuick]

Try just swapping the injector see if it moves .hell it could just be a bad plug or weak wire too

 

[BEATAV8]

You're doing it right you'll find it. Keep going on down the line to the ECM

 

[Toby_Goodmk]

tested voltage and the injector clicking by applying voltage to each injector through the harness. Each injector clicked. I am wondering if I have an open in the wire back to the ECM, or the ecm driver itself for terminal c12 I wish I had a way to lengthen my arms 15 ft to check continuity from terminal c12, to the ecm side of the injector harness in the engine bay, this would tell me if the wire is good.

 

[Toby_Goodmk]

another point. I have only driven the car VERY LIGHTLY about 10 miles with no fuel in the 6 cylinder obviously. Could I have caused any harm? A spit and sputter there, but no hold it to the floor and gun it WFO

 

[TT/Ameasap]

I would at least check compression on #6.

 

[Toby_Goodmk]

got 150 on the cylinder so it looks clear

 

[TurboBuRick]

Like mentioned, switch the injector with the one next door.

 

[Toby_Goodmk]

Like mentioned, switch the injector with the one next door.

If you read though my diag checks so far I have verified all injectors to be working, ohms, flow, injector harness to injector operation. This leads me to believe I have a weak wire somewhere between the C111 connector to the c12 terminal connection at the ECM, or the ECM driver itself. I ordered a injector harness from caspers today just to replace it as new. Dont want to be farting around taking this apart off the intake again.

 

[TurboBuRick]

Just trying to help...,

 

[Toby_Goodmk]

oh I appreciate it, just tell you what diag checks I performed

 

[fastblackracing]

Are you able to move the #4 injector harness plug over to the #6 Injector for a test? start the engine for 5-10 seconds and feel the header tubes for heat to see if that brings #6 to life? There is no heat marks on the threads of that plug.

 

[BobbyBuick]

thats what i do just pull the injector plug one at a time and see how it reacts. how do you really know the injector is okay? just because it clicks doesnt mean it is flowing fuel or did i miss something.i just try to keep it simple

 

[larry33kc]

Yes you can test the temp at the headers with a temp gun. That should tell you if it spraying fuel or if it's a spark issue.
I too would consider swapping #6 with another injector (2 or 4). That will isolate it further if the issues moves, then it's injector if it stays then it something else.

 

[Toby_Goodmk]

thats what i do just pull the injector plug one at a time and see how it reacts. how do you really know the injector is okay? just because it clicks doesnt mean it is flowing fuel or did i miss something.i just try to keep it simple

i did the injector to syringe to battery hook up to see if it would spray which they all do.

 

[Shawn N]

Toby have you tried swapping the #6 plug wire or tested the coil packs/module yet. A CCCI simulator is worth it's weight in gold boss.

 

[TT/Ameasap]

After taking a look at the #6 plug again, the ring on the plug has no soot and the porcelain looks like it was wet. Did the plug smell like fuel?
I would fire it up and put a temp gun on the exhaust..after 30 seconds you should be able to determine a problem.
Like mentioned above, check the coil pack.

Also check the plug itself. I have gotten cracked plugs right out of the box before. Heck i would buy another one and just try it for 1.99 to eliminate the simple stuff.

 

[Toby_Goodmk]

Toby have you tried swapping the #6 plug wire or tested the coil packs/module yet. A CCCI simulator is worth it's weight in gold boss.

I did test the coil pack for resistance on the 3/6, which was 10k ohms. If the coil pack were bad wouldnt the #3 not fire as well? I tested ohms on the wire, everything looks ok there.

CCCI simulator....hmm, have to look into that