Friggin misfire cyl 06

[lincoln_zero]

So 2+ months ago I did the spark plugs, and I replaced the ignition coil on cyl 6 because it read a misfire. Shortly after doing the work, the ECU gave me a misfire on cyl 6. I cleared it, and the code never came back.

Fast forward to this weekend, I tuned the LS with Torries tune. I flashed the track tune and after an hour of driving I got Engine Failsafe Mode. I scanned it, and I got no other DTC's except failsafe. So I returned to stock, drove it home. Next day I flashed with Torries street tune. Been driving a couple days and everything is good. Now today, I got failsafe mode with CEL and I scanned. Sure enough, there is the cyl 06 misfire.

So I need the vehicle for work tomorrow, so I swapped the cyl 06 coil with cyl 01 (opposite bank). Drove it 30 minute and it is driving good. No misfires.

So this cylinder has a brand new spark plug and coil done at the same time, and is the ONLY bank giving me this issue. Any thoughts?

 

[AmsterDutch]

Fuel injector issue? what did/does the plug look like?

 

[lincoln_zero]

Fuel injector issue? what did/does the plug look like?

Plug to the ignition coil? Looks mint. I have parked it until my mechanic can get it on a hoist (its my daily driver so this is gonna be fun).

 

[04_Sport_LS]

Maybe I'm misunderstanding somebody... but I think Dutch meant the electrode end of the spark plug.

 

[04_Sport_LS]

What brand of ignition coil? Cheap ones cause issues.

Also... double check that the coil connector is making good contact on the terminals of that coil.

 

[lincoln_zero]

Got the car back from the mechanic today.

He ran tests on the coils and wires, no issues. However, his scan picked up a weak 02 sensor bank 2. Thats the only lead we have.
The car usually sputtered on cold start, but today it didn't. Mechanic noted that he drove it and it behaved itself. So we are heavily leaning toward the 02 sensor being the culprit and will replace (might as well since it is showing up on the scan, and this car has thrown 02 sensors at me since September last year, which i interpreted as ignition coils and replaced).

Thats what I got so far, lemme know if you guys think this is a good place to start.

 

[lincoln_zero]

Are Bosche 02 sensors acceptable for this car? Anyone with experience?

 

[04_Sport_LS]

They are quirky. NTK seems to be more reliable.

 

[04_Sport_LS]

What brand of ignition coils have you been installing?

 

[AmsterDutch]

Are Bosche 02 sensors acceptable for this car? Anyone with experience?

I second that notion...go MotorCraft or NTK ...Bosche are no good...experience has proved this Bosche part to not respond properly on the LS

 

[AmsterDutch]

Got the car back from the mechanic today.

He ran tests on the coils and wires, no issues. However, his scan picked up a weak 02 sensor bank 2. Thats the only lead we have.
The car usually sputtered on cold start, but today it didn't. Mechanic noted that he drove it and it behaved itself. So we are heavily leaning toward the 02 sensor being the culprit and will replace (might as well since it is showing up on the scan, and this car has thrown 02 sensors at me since September last year, which i interpreted as ignition coils and replaced).

Thats what I got so far, lemme know if you guys think this is a good place to start.

I think it's the only place you can start without pouring a lot more money into the car...at least the Bank 2 is matching up with the 6th cylinder

 

[AmsterDutch]

It's a horse a piece really new MotorCraft Coil Over Plug and NGK Gapped at .101 or a O2 Sensor either way it's still under $100 dollars ...considerably cheap fix for the LS ...assuming once again this is the actual culprit

 

[lincoln_zero]

What brand of ignition coil? Cheap ones cause issues.
.

I used a brand called "Standard". I've used them before and they're good. I can't afford motorcraft coils unfortunately, as not only does the exchange range make them really pricey in Canada, but they seem to charge more. 8 coils Ford quoted me $1400.

On my first LS I used to own, I used to put the $10 eBay Chinese coils. Last about 4 years, but they worked lmao. I got away with it haha.

I think I will change over to the mustang 4.6 Accel coils. LS coils, even fomoco coils, are just trash.

 

[lincoln_zero]

...at least the Bank 2 is matching up with the 6th cylinder

That's what I noticed as well. Will update this week, gonna try and get the car in for the sensor replace. I'll try and avoid Bosche and locate a Ford brand. Thanks guys!

 

[04_Sport_LS]

Standards are good coils. So are the Borg Warner, (rebadged Standard), that O'Reilly's sells... and they have a lifetime warranty. The BW's were made in USA the last time I checked.

My BW's have 145k miles on them... and I think one is finally starting to "hiccup" occasionally.

 

[lincoln_zero]

OK update time.

02 sensor Bank 2/sensor 2 replaced with Ford Brand sensor.
Car drove well. Lots of power.
Aaaaaaaaand cylinder 06 misfire, failsafe mode is back.

Mechanic noted that the throttle body has been worked on, from the previous owner. He thinks the issue is there.

Another friend of mine thinks it's dirty fuel injectors.

I'm looking for your opinion guys. Where should I go next?

Edit: I noticed this morning on a cold start, both exhausts tips sounded like sputter until the rpm idled.

 

[lincoln_zero]

Fuel injector issue?

Is it safe to run Fuel Injector Cleaner through the LS? Or will this potentially piss it off even more?

 

[AmsterDutch]

Is it safe to run Fuel Injector Cleaner through the LS? Or will this potentially piss it off even more?

It won't hurt to run fuel injector cleaner through the gas lines but fuel injector cleaner is usually for maintaining clean injectors ...if the injector is to far gone it won't fix anything...but nevertheless it won't hurt anything either

 

[lincoln_zero]

It won't hurt to run fuel injector cleaner through the gas lines but fuel injector cleaner is usually for maintaining clean injectors ...if the injector is to far gone it won't fix anything...but nevertheless it won't hurt anything either

Ok good to know.
I read a few reviews of the STP injector cleaner that it cleared up sputtering on other peoples vehicles so I thought it was worth a shot.
I'll start pricing out injectors if you think that this is the next step.

 

[04_Sport_LS]

Is it safe to run Fuel Injector Cleaner through the LS? Or will this potentially piss it off even more?

I Seafoam my fuel tank every spring and fall. Yes it's ok to do. Don't bother with the STP. Use Seafoam instead.

 

[04_Sport_LS]

I'll start pricing out injectors if you think that this is the next step.

Throwing parts at it is like playing darts. Try to figure out what the problem is instead.

I'm not a programmer... but I suspect that when engine performance is increased through a "tune" it is done by increasing voltage to certain electrical components. I'd start with leaving the programmer on the shelf until you get this problem sorted out.

It seems you have a decent scanner. Can you monitor voltage in real time on the throttle body and individual injectors and coils when it acts up? That could tell alot about the cause.

Best I understand... there's only 2 ways to get a failsafe. Engine overheat... and a throttle body issue. I suspect that the misfire issue, (what ever it is), is causing feedback in the electrical system and it's going back to the PCM and causing the failsafe.

It's also possible that the source of the problem is the PCM itself.

There are others here that know more about this than I do... and about the LS electronics. I'm surprised they haven't chimed in yet.

 

[AmsterDutch]

Throwing parts at it is like playing darts. Try to figure out what the problem is instead.

I'm not a programmer... but I suspect that when engine performance is increased through a "tune" it is done by increasing voltage to certain electrical components. I'd start with leaving the programmer on the shelf until you get this problem sorted out.

It seems you have a decent scanner. Can you monitor voltage in real time on the throttle body and individual injectors and coils when it acts up? That could tell alot about the cause.

Best I understand... there's only 2 ways to get a failsafe. Engine overheat... and a throttle body issue. I suspect that the misfire issue, (what ever it is), is causing feedback in the electrical system and it's going back to the PCM and causing the failsafe.

It's also possible that the source of the problem is the PCM itself.

There are others here that know more about this than I do... and about the LS electronics. I'm surprised they haven't chimed in yet.

After purchasing the 2002 LSE I had the car go into fail safe on the way back home...due to cylinder 1 and 4 having misfires...if bad plugs/coils register in the throttle body then discard this post and I will go sit in the peanut gallery lol ....but if it's a separate issue we could add that to the list of causes of fail safe

 

[lincoln_zero]

Unfortunately my scanner can't detect live, from what I can tell.

From my experience, misfires can cause ETC failsafe.
The tune actually is helping, cause it's exposing a weakness in my system. The ETC failsafe only happens when in WOT. Only then, it throws misfire Cylinder 6 and goes into failsafe.

If I keep RPM's under 3k then it drives no DTC's.
It did not do this before I tuned it. So pulling the tune, will make it more difficult to discover the issues.

Coils are new. Plugs are new. I swapped coils from cyl 6 to cyl 1, and still cyl 6 misfire, and only cylinder 6.

So this leads me to believe that it's not the coil. Could be the plug? Did I get a bad plug from NGK?

 

[AmsterDutch]

Unfortunately my scanner can't detect live, from what I can tell.

From my experience, misfires can cause ETC failsafe.
The tune actually is helping, cause it's exposing a weakness in my system. The ETC failsafe only happens when in WOT. Only then, it throws misfire Cylinder 6 and goes into failsafe.

If I keep RPM's under 3k then it drives no DTC's.
It did not do this before I tuned it. So pulling the tune, will make it more difficult to discover the issues.

Coils are new. Plugs are new. I swapped coils from cyl 6 to cyl 1, and still cyl 6 misfire, and only cylinder 6.

So this leads me to believe that it's not the coil. Could be the plug? Did I get a bad plug from NGK?

Can you upload a picture of the spark plug so we can get a look at the igniter? How does the connector look on the Coil over plug? Does the connector still clip and lock on the Coil? Did you use a Ohm/Volt meter to check continuity between the wires from the coil and it's power source? It seems odd that only one fuel injector would be bad but until you test it you can't rule it out...

 

[lincoln_zero]

Can you upload a picture of the spark plug so we can get a look at the igniter? How does the connector look on the Coil over plug? Does the connector still clip and lock on the Coil? Did you use a Ohm/Volt meter to check continuity between the wires from the coil and it's power source? It seems odd that only one fuel injector would be bad but until you test it you can't rule it out...

Thats a great idea. I will test it this week for voltage.

Connector looked fine when i took it out. Not all of them clip in tight. I think a couple on bank 1 didnt make the "click" sound, but nothing on bank 1 is throwing misfire codes. I'll take a closer inspection when I test the wire for voltage.

I'll inspect the plug as well. Its definitely an incomplete burn, I heard it through my exhaust on the way home from work. Very faint pops.