Elco

uh... spark plugs or coils? anyone?

j50ny

iTrader: (8)

Glad you were able to narrow it down a bit. For my friend's car, his tb was the issue. Even though you know the cylinder, now you still have to figure out the cause. May want to check the coil packs. If you don't have an ohm meter, you can swap coil packs (put the one from cylinder 6 in a different location, just don't mess up the harness location) and see if the misfire has moved to the new cylinder. Since you tested the spark plugs already, you can try that.

Oh...and I was just joking about the work/being busy thing. I only said it because I was at work and would clearly rather be doing ANYTHING else but work!!

SonicVQ

It could be a coil or plug, but let's continue to diagnose the issue. Normally a bad coil will function fine at idle, but not at high RPM.

Misfires are caused by poor ignition or a lean fuel mixture. The fuel trims will tell us if the ECU is adding or removing fuel.

The next step is to look at the fuel trims: long term fuel trim (LTFT) and short term fuel trim (STFT) This will tell us if the ECU is adding or removing fuel. Our engine is divided up into 2 banks of 3 cylinders.

With the car running, fire up Torque, connect to the car and touch "Realtime information". Add 4 displays: LTFT bank 1, STFT bank 1, LTFT bank 2 and STFT bank 2

Post your fuel trims when you can.

DevilsG37s

Will check the fuel trims today.

Quick update. When I got back from work I went and removed the 6th and the 4th plugs and cleaned them with ACdelco and swapped them to check for any difference. I couldn't check the car after becaue I'm working 12 duty and I'm exhausted. Hope I can test the car now before going to work. I Want to source out whether if the issue is plugs or coils at first. Then move to the next step.

SonicVQ

How did the 3 month old plugs look? Was #4 any different than #6?
Did replace them with the same type? (FXE24HR-11)

Cylinder #4 and #6 are part of bank 2. It will be interesting to see if the fuel trim on bank 2.

DevilsG37s

I only swapped them together. Meaning 4th plug is now installed in the 6th cylinder and the 6th plug is in the 4th cylinder now. After cleaning both of them. Because the 4th cylinder wasn't reporting any misfiring. Yes they're all FXE24HR11.

It would've been so helpful if I took some pictures of plugs for you guys.

Anyway, They look very bad and has a lot of deposit buildup on them. Specially the 6th plug. I also smelt a really familiar smell that I recognized. About 2 months ago I was trying to clean the cylinders through the brake booster hose. And because we don't have Seafoam around here, I used the STP multipurpose motor treatment the same way when using the Seafoam through the brake booster and the cylinders internals along with the plug deposit smelled exactly like when I was in the process of cleaning the cylinders before.
That brings me to notice that I was noticing these shakes after that one time cleaning and they were barely noticeable. Not like what I described in the OP.

And when I was in the process of swapping the plugs, You know you have to remove the throttle body from the manifold to reach the 6th plug. So I inspected the tb and found out it was dirty as $hit from the inside. I cleaned it up pretty nice and cleaned the reachable inner portion of the manifold too.
Also did ECU reset and idle position re-learn though the pedal.

Results:

I noticed a lot of improvement in the car behavior when idling and when driving. No more whole car shakes.. only slight shakes that is still noticeable and not as frequent as before accompanied with a hissing sound from under the car with every shake. Could it be a leaking exhaust as I have test pipes installed.

I will post another test report soon to see if there is any improvements in cylinder 6.

DevilsG37s

I have an ohm meter. Today is my last day in the night shift. I'll have a long off so I think I will replace all the six plugs and check the coil packs too.

How to know if a coil pack is shot?

it's cool man.. aren't we all busy in some stuff to do

Thanks

DevilsG37s

Here is a fuel trim screen shot:





This is taken while the car is idling.

I don't quite understand what I'm looking at here. Someone care to explain.

Here is the test report just taken:

Test report:
------------------
MID:$01 TID:$83
- O2 Bank 1 Sensor 1
Max: 65.535V Min: 0.4V
Test result value: 2.145V
PASS
----
MID:$01 TID:$84
- O2 Bank 1 Sensor 1
Max: 4.399V Min: 0V
Test result value: 2.145V
PASS
----
MID:$01 TID:$85
- O2 Bank 1 Sensor 1
Max: 2.149V Min: 0V
Test result value: 1.77V
PASS
----
MID:$01 TID:$86
- O2 Bank 1 Sensor 1
Max: 65.535V Min: 2.25V
Test result value: 5.065V
PASS
----
MID:$01 TID:$87
- O2 Bank 1 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.528
PASS
----
MID:$01 TID:$88
- O2 Bank 1 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.52
PASS
----
MID:$01 TID:$89
- O2 Bank 1 Sensor 1
Max: 0.449 Min: -32.768
Test result value: -0.018
PASS
----
MID:$02 TID:$07
Minimum sensor Voltage for test cycle(calculated) - O2 Bank 1 Sensor 2
Max: 0.17V Min: 0V
Test result value: 0.17V
PASS
----
MID:$02 TID:$08
Maximum sensor Voltage for test cycle(calculated) - O2 Bank 1 Sensor 2
Max: 2.55V Min: 0.7V
Test result value: 0.7V
PASS
----
MID:$02 TID:$80
- O2 Bank 1 Sensor 2
Max: 1.19V Min: 0V
Test result value: 0.7V
PASS
----
MID:$02 TID:$81
- O2 Bank 1 Sensor 2
Max: 2.55V Min: 0.48V
Test result value: 0.54V
PASS
----
MID:$02 TID:$82
- O2 Bank 1 Sensor 2
Max: 3.9S Min: 0S
Test result value: 0.4S
PASS
----
MID:$05 TID:$83
- O2 Bank 2 Sensor 1
Max: 65.535V Min: 0.4V
Test result value: 2.08V
PASS
----
MID:$05 TID:$84
- O2 Bank 2 Sensor 1
Max: 4.399V Min: 0V
Test result value: 2.08V
PASS
----
MID:$05 TID:$85
- O2 Bank 2 Sensor 1
Max: 2.149V Min: 0V
Test result value: 1.755V
PASS
----
MID:$05 TID:$86
- O2 Bank 2 Sensor 1
Max: 65.535V Min: 2.25V
Test result value: 5.065V
PASS
----
MID:$05 TID:$87
- O2 Bank 2 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.584
PASS
----
MID:$05 TID:$88
- O2 Bank 2 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.46
PASS
----
MID:$05 TID:$89
- O2 Bank 2 Sensor 1
Max: 0.449 Min: -32.768
Test result value: 0.22
PASS
----
MID:$06 TID:$07
Minimum sensor Voltage for test cycle(calculated) - O2 Bank 2 Sensor 2
Max: 0.17V Min: 0V
Test result value: 0.17V
PASS
----
MID:$06 TID:$08
Maximum sensor Voltage for test cycle(calculated) - O2 Bank 2 Sensor 2
Max: 2.55V Min: 0.7V
Test result value: 0.7V
PASS
----
MID:$06 TID:$80
- O2 Bank 2 Sensor 2
Max: 1.19V Min: 0V
Test result value: 0.17V
PASS
----
MID:$06 TID:$81
- O2 Bank 2 Sensor 2
Max: 2.55V Min: 0.48V
Test result value: 0.55V
PASS
----
MID:$06 TID:$82
- O2 Bank 2 Sensor 2
Max: 3.9S Min: 0S
Test result value: 0.4S
PASS
----
MID:$3c TID:$81
- EVAP Monitor (0.040")
Test incomplete or dependant test failed
--
MID:$3c TID:$82
- EVAP Monitor (0.040")
Test incomplete or dependant test failed
--
MID:$3d TID:$83
- EVAP Monitor (0.020")
Max: 655.34998V Min: 0.02V
Test result value: 0.04V
PASS
----
MID:$41 TID:$81
- O2 Heater Monitor Bank 1 - Sensor 1
Max: 4.779V Min: 0.39V
Test result value: 1.2V
PASS
----
MID:$42 TID:$80
- O2 Heater Monitor Bank 1 - Sensor 2
Max: 4.71V Min: 0.24V
Test result value: 1.54V
PASS
----
MID:$45 TID:$81
- O2 Heater Monitor Bank 2 - Sensor 1
Max: 4.779V Min: 0.39V
Test result value: 1.195V
PASS
----
MID:$46 TID:$80
- O2 Heater Monitor Bank 2 - Sensor 2
Max: 4.71V Min: 0.24V
Test result value: 1.42V
PASS
----
MID:$81 TID:$80
- Fuel System Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$81 TID:$81
- Fuel System Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$82 TID:$80
- Fuel System Monitor Bank 2
Test incomplete or dependant test failed
--
MID:$82 TID:$81
- Fuel System Monitor Bank 2
Test incomplete or dependant test failed
--
MID:$a2 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 1 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a2 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 1 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a3 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 2 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a3 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 2 Data
Max: 65,535Count Min: 0Count
Test result value: 50Count
PASS
----
MID:$a4 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 3 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a4 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 3 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a5 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 4 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a5 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 4 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a6 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 5 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a6 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 5 Data
Max: 65,535Count Min: 0Count
Test result value: 2Count
PASS
----
MID:$a7 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 6 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a7 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 6 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
End of report.

DevilsG37s

Here is another one taken 10 min after the first one:

Test report:
------------------
MID:$01 TID:$83
- O2 Bank 1 Sensor 1
Max: 65.535V Min: 0.4V
Test result value: 2.145V
PASS
----
MID:$01 TID:$84
- O2 Bank 1 Sensor 1
Max: 4.399V Min: 0V
Test result value: 2.145V
PASS
----
MID:$01 TID:$85
- O2 Bank 1 Sensor 1
Max: 2.149V Min: 0V
Test result value: 1.77V
PASS
----
MID:$01 TID:$86
- O2 Bank 1 Sensor 1
Max: 65.535V Min: 2.25V
Test result value: 5.065V
PASS
----
MID:$01 TID:$87
- O2 Bank 1 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.69
PASS
----
MID:$01 TID:$88
- O2 Bank 1 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.756
PASS
----
MID:$01 TID:$89
- O2 Bank 1 Sensor 1
Max: 0.449 Min: -32.768
Test result value: -0.012
PASS
----
MID:$02 TID:$07
Minimum sensor Voltage for test cycle(calculated) - O2 Bank 1 Sensor 2
Max: 0.17V Min: 0V
Test result value: 0.17V
PASS
----
MID:$02 TID:$08
Maximum sensor Voltage for test cycle(calculated) - O2 Bank 1 Sensor 2
Max: 2.55V Min: 0.7V
Test result value: 0.7V
PASS
----
MID:$02 TID:$80
- O2 Bank 1 Sensor 2
Max: 1.19V Min: 0V
Test result value: 0.65V
PASS
----
MID:$02 TID:$81
- O2 Bank 1 Sensor 2
Max: 2.55V Min: 0.48V
Test result value: 0.56V
PASS
----
MID:$02 TID:$82
- O2 Bank 1 Sensor 2
Max: 3.9S Min: 0S
Test result value: 0.4S
PASS
----
MID:$05 TID:$83
- O2 Bank 2 Sensor 1
Max: 65.535V Min: 0.4V
Test result value: 2.08V
PASS
----
MID:$05 TID:$84
- O2 Bank 2 Sensor 1
Max: 4.399V Min: 0V
Test result value: 2.08V
PASS
----
MID:$05 TID:$85
- O2 Bank 2 Sensor 1
Max: 2.149V Min: 0V
Test result value: 1.755V
PASS
----
MID:$05 TID:$86
- O2 Bank 2 Sensor 1
Max: 65.535V Min: 2.25V
Test result value: 5.065V
PASS
----
MID:$05 TID:$87
- O2 Bank 2 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.872
PASS
----
MID:$05 TID:$88
- O2 Bank 2 Sensor 1
Max: 65.535 Min: 0.3
Test result value: 0.93
PASS
----
MID:$05 TID:$89
- O2 Bank 2 Sensor 1
Max: 0.449 Min: -32.768
Test result value: 0.232
PASS
----
MID:$06 TID:$07
Minimum sensor Voltage for test cycle(calculated) - O2 Bank 2 Sensor 2
Max: 0.17V Min: 0V
Test result value: 0.17V
PASS
----
MID:$06 TID:$08
Maximum sensor Voltage for test cycle(calculated) - O2 Bank 2 Sensor 2
Max: 2.55V Min: 0.7V
Test result value: 0.7V
PASS
----
MID:$06 TID:$80
- O2 Bank 2 Sensor 2
Max: 1.19V Min: 0V
Test result value: 0.65V
PASS
----
MID:$06 TID:$81
- O2 Bank 2 Sensor 2
Max: 2.55V Min: 0.48V
Test result value: 0.49V
PASS
----
MID:$06 TID:$82
- O2 Bank 2 Sensor 2
Max: 3.9S Min: 0S
Test result value: 0.4S
PASS
----
MID:$21 TID:$80
- Catalyst Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$21 TID:$82
- Catalyst Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$22 TID:$80
- Catalyst Monitor Bank 2
Test incomplete or dependant test failed
--
MID:$22 TID:$82
- Catalyst Monitor Bank 2
Test incomplete or dependant test failed
--
MID:$35 TID:$80
-
Max: 13° Min: -13°
Test result value: 2°
PASS
----
MID:$35 TID:$82
-
Max: 13° Min: -13°
Test result value: 1°
PASS
----
MID:$35 TID:$84
-
Max: 499ms Min: 0ms
Test result value: 98ms
PASS
----
MID:$35 TID:$85
-
Max: 10,779ms Min: 0ms
Test result value: 10ms
PASS
----
MID:$36 TID:$80
-
Max: 13° Min: -13°
Test result value: 4.5°
PASS
----
MID:$36 TID:$82
-
Max: 13° Min: -13°
Test result value: 0°
PASS
----
MID:$36 TID:$84
-
Max: 499ms Min: 0ms
Test result value: 103ms
PASS
----
MID:$36 TID:$85
-
Max: 2,379ms Min: 0ms
Test result value: 20ms
PASS
----
MID:$3c TID:$81
- EVAP Monitor (0.040")
Test incomplete or dependant test failed
--
MID:$3c TID:$82
- EVAP Monitor (0.040")
Test incomplete or dependant test failed
--
MID:$3d TID:$83
- EVAP Monitor (0.020")
Max: 655.34998V Min: 0.02V
Test result value: 0.09V
PASS
----
MID:$41 TID:$81
- O2 Heater Monitor Bank 1 - Sensor 1
Max: 4.779V Min: 0.39V
Test result value: 1.2V
PASS
----
MID:$42 TID:$80
- O2 Heater Monitor Bank 1 - Sensor 2
Max: 4.71V Min: 0.24V
Test result value: 1.54V
PASS
----
MID:$45 TID:$81
- O2 Heater Monitor Bank 2 - Sensor 1
Max: 4.779V Min: 0.39V
Test result value: 1.195V
PASS
----
MID:$46 TID:$80
- O2 Heater Monitor Bank 2 - Sensor 2
Max: 4.71V Min: 0.24V
Test result value: 1.42V
PASS
----
MID:$81 TID:$80
- Fuel System Monitor Bank 1
Max: 130.98999% Min: 77.00999%
Test result value: 95.9%
PASS
----
MID:$81 TID:$81
- Fuel System Monitor Bank 1
Test incomplete or dependant test failed
--
MID:$82 TID:$80
- Fuel System Monitor Bank 2
Max: 130.98999% Min: 77.00999%
Test result value: 97.93999%
PASS
----
MID:$82 TID:$81
- Fuel System Monitor Bank 2
Test incomplete or dependant test failed
--
MID:$a2 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 1 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a2 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 1 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a3 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 2 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a3 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 2 Data
Max: 65,535Count Min: 0Count
Test result value: 56Count
PASS
----
MID:$a4 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 3 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a4 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 3 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a5 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 4 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a5 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 4 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a6 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 5 Data
Max: 65,535Count Min: 0Count
Test result value: 1Count
PASS
----
MID:$a6 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 5 Data
Max: 65,535Count Min: 0Count
Test result value: 2Count
PASS
----
MID:$a7 TID:$0b
EWMA Misfire counts (average) for last 10 drive cycles - Misfire Cylinder 6 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
MID:$a7 TID:$0c
Misfire counts for last/current driving cycles(calculated) - Misfire Cylinder 6 Data
Max: 65,535Count Min: 0Count
Test result value: 0Count
PASS
----
End of report.

Selym

What kind of air filters are you using? Your intake tracts should be clean downstream of the filters. You definitely don't want your engine ingesting dust.

DevilsG37s

Yes. Thank you for reminding me regarding this point.

If you guys are running the filter heads that come with the Z1 cold air intake kit, please change them as soon as possible as they allow a lot of dust to pass if you're in a dusty area.

I changed the heads only with genuine Apexi filter heads and I've checked them after running them for sometime and they were excellent in keeping the dust out. You can google Apexi filtration test for an old comparison for how Apexi filter is better than many filters in both filtration and power making. I will also use some filter wraps to cover the filters. This would help more in protecting the filter from any dust accumulation that may end up in the engine.

Another plus when swapped to Apexi that the car felt a lot more smoother when accelerating with a slightly noticeable power increase.


For anyone interested, here is the Apexi head part number that you can froogle: APEXi 500-A023

You'll also need these reducers/couplers with the same size to connect them: http://www.ebay.com/itm/190924147164?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

SonicVQ

Fuel trims look normal. If you add the short + long term, they should be around -10 to +10.

More in fuel trims here:
Fuel trim can be a valuable diagnostic tool - Eastern Manufacturing

Will post more tomorrow...

DevilsG37s

Good..

I would like you to take a look at the test results for cylinder #6.

I did more than 5 tests and they're all showing Zero misfiring on the 6th one. Isn't that telling us that the issue is narrowed to spark plugs?

I'm just thinking out loud here.

j50ny

iTrader: (8)

This guy has a few videos to test coil packs, injectors, etc.


(sorry for the short reply...actually working at work today so can't type out the instructions)

DevilsG37s

That's more than enough man.

Thanks a lot