matrix11229

I replaced my old spark plugs today with NGK V-Power copper plugs (BKR5E-11) and got Cylinder 6 Misfire code (0603).

The engine runs smooth but it jerks once every 4 seconds. The Idle jumps a little bit during the jerking and I can see and feel how the engine "jupms" and vibrates every 4 sec.
I think it's coming from the firewall side near the IACV.

Where can I get a picture of Cylinder 6 location and what should I do ?
Could it be the plug gap ? (I gapped them to 0.044 according to Nissan)
Or I put too much Anti Seize or Over tighten the plug or coil ?


Also besides the jerking I hear some slight knocking noise once every few seconds from the IACV area. (I had this noise before the plugs replacement. I hear it for the last two weeks)

matrix11229

Also I can feel the jerking only when the car sits (with shifter in P or N and sometimes in D).

NmexMAX

iTrader: (22)

maximan57

Try reseating that coil pack on that plug. If that doesn't do it get a new coil pack for that cylinder.

matrix11229

Thanks guys ! I'm gonna reseat the coil today.

Can I swap the front coil packs ? This way I can check if it's a bad coil or plug.

NmexMAX

iTrader: (22)

What do you mean swap?

If you mean swap from fron to rear. No, the rears are longer.

Batxel

iTrader: (1)

Make sure they're torqued to spec also.

loverholic

iTrader: (3)

i think he meant swaping the coils wiht another one on the frnt back....

matrix11229

I took the coil out and inserted it back but I still heard some detonation/misfire once in a while.

Then I drove 5 miles and turned off the engine. After 10 min I turned it on and the CEL dissapeared ! No more misfiring is felt but I still have some hesitations once in a while in Idle, but when it's on D it's very smooth.

I had CEL for rear O2 sensor and 0705-Evaporative control system before I replaced the plugs and now the CEL dissapeared.

So I checked for ghost codes and the only code that remained is the Evap control system .

matrix11229

I get a misfire again but no CEL. It happens only when I come to a full stop. When the car sits the engine "jumps" once every 2 minutes and then runs smooth until the next detonation.

Tomorrow I will take out the spark plug from cylinder 6, inspect it and put it back again, and if it's not gonna help I'm gonna go to Strauss and exchange that single plug.

I don't believe that a coil could go bad just because I replaced the spark plugs.

Trajiksmax

Sounds to me as if you might have a bad plug on your hands. Could be bad electrode, bad gap, anti-seize on the tip. I think your going about this the right way. Good Luck.

matrix11229

I took the plug out today and found the insulator nose in contact with firing tip which means there is no gap at all (0.00).
I remember I set the gap to 0.044 and probably because of the misfire/detonation the insulator nose bended.

I checked the nearby plug and it was ok. So I put the plug back and the engine runs smooth now. I didn't drive it yet so I don't know if it will misfire again.

Did anyone see their insulator nose bent like this ? And is this usually caused by a misfire ?

Trajiksmax

You might have torqued the plugs too tight. They only need to be snug, remeber there is a washer on the plugs.

sky jumper

lets get some terminology straight - there is a center electrode (which is the copper piece with a V in it), a white insulator tip or nose that surrounds the center electrode, and there is the ground electrode that curves around to form the gap.

are you saying the gound electrode was bent and contacting the center electrode?? holy shee-it! i find it really hard to believe a misfire could cause that. I'm wondering if it had contact with the piston. are you sure it was a bkr5e11 that you put in?

take the plug out, double check its physical size against your old plugs, and point a flash light down in there to inspect the piston top.

matrix11229

You right , the ground electrode was bent and contacting the center electrode.
Also the ground electrode tip was covered with anti-seize that leaked from the threads(I put too much of it on the threads). I checked the nearby plug and the gr.electrode is coverd by it too. And I think I torqued the plugs too tight.
I'm very sure I used bkr5e11 and their physical size is the same as my old NGK Platinums.

The engine runs very smooth now after I regapped the plug but I didn't drive it yet. I'm gonna drive tomorrow and let you know how it feels.

matrix11229

According to NGK, a detonation could cause the bending of ground electrode.

Quote:

Q: What is detonation?

Detonation is a spark plugs worst enemy. It can break insulators and ground electrodes. Spark plug temperatures can reach in excess of 3000 °F.
Detonation, in simple terms, is a violent uncontrolled burn of the air/fuel mixture, which occurs when excessive heat and cylinder pressure causes the air/fuel mixture to spontaneously ignite.
End of Quote.

So my question is what could cause the Detonation ? Anti-seize on ground electrode or overtorqued plug ?

sky jumper

detonation is the same thing as knock (which the knock sensor system is designed to prevent). it typically is caused by burning low octane fuel, but again, the KS is supposed to prevent it. theoretically, I think it is still possible for detonation to occur even when the ignition timing is fully retarded if cylinder compression is high enough (due to combustion chamber deposits). I believe Nissan had an old TSB for such a condition, and prescribed the use of fuel injector cleaner poured straight down the spark plug hole to dissolve the deposits.

if I were you I'd check your compression. buy or borrow a compression tester from an auto parts store and check it. it's easy to do. I'll bet you're a bit over the spec of 185psi. if so, a piston soak may be in order to get rid of those deposits.

NmexMAX

iTrader: (22)

Get colder plugs.

matrix11229

I thought that engine knock sounds like slight ticking of the valves during acceleration, which usually happens when you use low octane fuel (89), but no vibration is felt during that knock.

The sound that I heard was completely different. I heard a loud noise like the engine was kicked by a hammer, and it felt like the engine jumps out from the car and lands back. There was only a single detonation once evry few minutes and only when the car sits with shifter on D or N.

I can try checking the compression but 1. It will cost me money 2. I don't think the compression could go bad immediately after I replaced the spark plugs.

Most likely the problem was due to overtorqued plug, or coil that didn't seat well on the plug.

sky jumper

kicked by a hammer? jeesh. yeah you've got something else going on then. I really can't help you. you can try retorquing that plug, but something tells me that wont fix it.

please keep us posted as to what you find. I am very interested in this.

matrix11229

After I took the plug out and regaped it(the ground electrode was bent), the car drives fine. No vibration when the car sits and it drives very smooth now.

shahidw

I am having same issue in my 02 maxima SE new plugs were installed by the mechanic and engine started shaking while in D and P but it is fine when you start driving. I will ask mechanic to check the plugs again.

eddie982

iTrader: (10)

Yep, and make sure your mech has a gap tool