Cylinder 6 Misfire

[Ironhydroxide]

So. the Car: EG33 powered XT6 (like huck). running STOCK SVX ECU, '92

the problem: Cylinder 6 DOES NOT FIRE. (as far as I can tell EVER, explanation in points below)

what I have done:
(1) Pulled codes: 55 (EGR TEMP) not related as far as I can tell, don't even have O2 Codes

(2) Pulled injector leads till i find the one without a miss (turned out to be #6)

(3) Swapped coils with known good coil, to no avail (even used Spark checker, no spark on #6 no matter what coil I use)

(4) Swapped injectors between #4 and #6, Still misses on #6

(5) Checked Continuity on BOTH wires from the coil connector to the Ignitor (tested good)

(6) Checked Continuity on ALL wires FROM Ignitor to ECU (tested good)

(7) Swapped Ignitor with known good unit (still misses)

(8) Swapped ECU with Known good Unit (still misses, Codes pull the same, always a 55)

(9) might be related.... Replaced Crank Angle sensor, cleaned both cam angle sensors of debris.

(10) Checked Compression. All were over 120

(11) checked plugs, All but #6 looked Tan (propper) #6 was WHITE, Replaced #6 plug in fear of a bad unit and checked after a spirited drive...Still White (NGK Iridiums)

(12) Searched all over for anyone having the same problem....nada


Supplemental info: Since I did the engine swap i have had the miss... I did NOT hear the engine run in the original SVX, (was a sad SVX, all because of a trans, someone parted the whole thing, I got it with no trans, diff, lights, and wanted interior parts). The car is DEAD reliable, Starts always the first key turn. Every once in a while i'll get the idle lope in Neutral or coasting clutch in... Only every once in a (long) while does it stall because of this.


i am sure there are things I am missing... BUT any help would be very appreciated

Rusty

[oab_au]

Originally Posted by Ironhydroxide

So. the Car: EG33 powered XT6 (like huck). running STOCK SVX ECU, '92

the problem: Cylinder 6 DOES NOT FIRE. (as far as I can tell EVER, explanation in points below)

what I have done:
(1) Pulled codes: 55 (EGR TEMP) not related as far as I can tell, don't even have O2 Codes

(2) Pulled injector leads till i find the one without a miss (turned out to be #6)

(3) Swapped coils with known good coil, to no avail (even used Spark checker, no spark on #6 no matter what coil I use)

(4) Swapped injectors between #4 and #6, Still misses on #6

(5) Checked Continuity on BOTH wires from the coil connector to the Ignitor (tested good)

(6) Checked Continuity on ALL wires FROM Ignitor to ECU (tested good)

(7) Swapped Ignitor with known good unit (still misses)

(8) Swapped ECU with Known good Unit (still misses, Codes pull the same, always a 55)

(9) might be related.... Replaced Crank Angle sensor, cleaned both cam angle sensors of debris.

(10) Checked Compression. All were over 120

(11) checked plugs, All but #6 looked Tan (propper) #6 was WHITE, Replaced #6 plug in fear of a bad unit and checked after a spirited drive...Still White (NGK Iridiums)

(12) Searched all over for anyone having the same problem....nada


Supplemental info: Since I did the engine swap i have had the miss... I did NOT hear the engine run in the original SVX, (was a sad SVX, all because of a trans, someone parted the whole thing, I got it with no trans, diff, lights, and wanted interior parts). The car is DEAD reliable, Starts always the first key turn. Every once in a while i'll get the idle lope in Neutral or coasting clutch in... Only every once in a (long) while does it stall because of this.


i am sure there are things I am missing... BUT any help would be very appreciated

Rusty

Rusty you have covered most of the points. The points that I have pointed out don't leave much.
I am assuming that No.6 is the rear on the US drivers side.?
I don't see any vacation of power getting to the injector.
The White No.6, could be a very lean mixture, or that no fuel is present when the spark happens.

Check that there is 12V at the injector and that injector is actual passing fuel.

Harvey.

[Ironhydroxide]

I'll certainly check this..... Buy I can physically hear the injector clicking when I re attach the lead, and stop when I remove it.

I am quite sure it is something to do with the coil..... But have no idea what or how

[icingdeath88]

Originally Posted by oab_au

Rusty you have covered most of the points. The points that I have pointed out don't leave much.
I am assuming that No.6 is the rear on the US drivers side.?
I don't see any vacation of power getting to the injector.
The White No.6, could be a very lean mixture, or that no fuel is present when the spark happens.

Check that there is 12V at the injector and that injector is actual passing fuel.

Harvey.

Rear on the passenger's side.

[Ironhydroxide]

Um, no, REAR Left Side of the engine. IIRC the Engine goes as such

Front
2 1
4 3
6 5
Back

OH, and another weird thing....While I was having Crank angle sensor problems (or when I pull the crank angle sensor out of the hole without disconnecting) the Engine throws TONZ of codes (which i would expect) BUT the interesting part. It threw EVERY Injector SAVE #6 (maybe because i had #6 disconnected while cranking because of the problem I've had).

[Cam]

Originally Posted by Ironhydroxide

Um, no, REAR Left Side of the engine. IIRC the Engine goes as such

Front
2 1
4 3
6 5
Back

OH, and another weird thing....While I was having Crank angle sensor problems (or when I pull the crank angle sensor out of the hole without disconnecting) the Engine throws TONZ of codes (which i would expect) BUT the interesting part. It threw EVERY Injector SAVE #6 (maybe because i had #6 disconnected while cranking because of the problem I've had).

Have you tried swapping an ignition module from a known working one?

[Ironhydroxide]

Ignition module???

Ive swapped Coils(multiple), Ignitor, and ECU..... From the swap that's all the Electronics I have there in place for ignition (and is all that is in the wiring diagrams)

[icingdeath88]

Originally Posted by Ironhydroxide

Um, no, REAR Left Side of the engine. IIRC the Engine goes as such

Front
2 1
4 3
6 5
Back

My mistake. I got turned around. I would still swap the injector to test it, that's the next thing I can think of.

[Ironhydroxide]

Ok, see #4

[92snowmachine]

possibly the reluctor wheel for the crank sensor is bent or dirty on the tab for #6. do you have access or know anyone with an oscilloscope? you could make sure what you are ruling in and ruling out a lot better and save time swapping parts to see if it changed anyting.

[icingdeath88]

Did you check the wiring to the injector?

[oab_au]

Originally Posted by Ironhydroxide

I'll certainly check this..... Buy I can physically hear the injector clicking when I re attach the lead, and stop when I remove it.

I am quite sure it is something to do with the coil..... But have no idea what or how

OK, I missed this bit when I looked last night.

even used Spark checker, no spark on #6 no matter what coil I use)

Check the lead to the coil to see if there is 12V on the black/white one. Stick a pin in the wire at the coil, check to ground, if there is none, check the wire back at the Igniter.

Got the sides mixed up, I am RHD.

Harvey.

[92snowmachine]

you can bench test the coil by supplying power and tapping the ground side to ground, easiest to do with a plug in the end that is touching ground. if it fires off the car but not in the car you have a wiring or signal issue.

[oab_au]

Originally Posted by 92snowmachine

you can bench test the coil by supplying power and tapping the ground side to ground, easiest to do with a plug in the end that is touching ground. if it fires off the car but not in the car you have a wiring or signal issue.

Be careful about doing this as the coil will draw about 24 amps, if it is grounded. and it won't take long to burn it out.
When it has the Igniter grounding it, and the current gets to 4amps, it holds the current at that level, so it does not get higher.

Harvey.

[Ironhydroxide]

I have checked the coil by using and Inline spark tester, grounding the Bolt, holding the Coil in my hand, and plugging the Coil lead into a separate coil's lead...then it fired, ONce I plugged it into it's own lead. No fire. From there I checked continuity to the ignitor from BOTH leads in the No.6 coil. Good connection( even with shaking wires) then from ALL the wires in the Ignitor to the ECU. Still good connection.

When I get some free time again, I will Check for 12V at the Coil. and at that time I plan to RE-Check the compression, and use my NEW Boroscope in the cylinder (might be mechanical problem.....) and Which reluctor wheel does the ECU get Coil signals from? The Left side Cam? or one of the ones on the crank?