Bad spark plugs

I just wanted to make this thread for you guys. I will be doing my spark plugs this weekend. My cars been misfiring from 2nd to 3rd lately and 3rd to 4th a bit. Upon restart car is fine. I switched the ignition coils and still misfires in same cylinder. The spark plugs I have are the OEM NGK ones and have about 45k miles on them. I will take pics of the old vs new so we can all take a look at what kind of stress they've been under w/ the power my engine has. Should be pretty interesting!.

Originally Posted by MalibuMafiaV

I just wanted to make this thread for you guys. I will be doing my spark plugs this weekend. My cars been misfiring from 2nd to 3rd lately and 3rd to 4th a bit. Upon restart car is fine. I switched the ignition coils and still misfires in same cylinder. The spark plugs I have are the OEM NGK ones and have about 45k miles on them. I will take pics of the old vs new so we can all take a look at what kind of stress they've been under w/ the power my engine has. Should be pretty interesting!.

Remember what I said a while back about going one range colder on the plugs ? Maybe that`s what it`s asking for....

P.S.: Check the gaps on the old plugs to see if they all remained constant, or if some of them closed up a bit....

Originally Posted by Fast Bob

Remember what I said a while back about going one range colder on the plugs ? Maybe that`s what it`s asking for....

P.S.: Check the gaps on the old plugs to see if they all remained constant, or if some of them closed up a bit....

Yeah I might want to go with the one step colder ones your right. But I already have OEMs that have been sitting in my closet for months. I might as well use the ones that are free first ya know? lol.

I will definitely look at the gaps. I will post pics so we can all take a look and see whats happening with them.

It may have closed from the carbon build up

One thing you might want to get Mal is a egt sensor just to see how hot your exhaust gets.

I remember when I ran rich on my MR2 SC it melted my cat's diaphragm inside during a track day. Also why I had to switch to a test pipe during track days.

Plus when you over-rev/bounce rev-liter or pre-detonate a combustion chamber, it demolishes the spark plug tip along with it's surrounding ceramic. I'll post pics when I get a chance. This will not only cause a misfire but also overheating.

Originally Posted by av98

It may have closed from the carbon build up

One thing you might want to get Mal is a egt sensor just to see how hot your exhaust gets.

I remember when I ran rich on my MR2 SC it melted my cat's diaphragm inside during a track day. Also why I had to switch to a test pipe during track days.

Plus when you over-rev/bounce rev-liter or pre-detonate a combustion chamber, it demolishes the spark plug tip along with it's surrounding ceramic. I'll post pics when I get a chance. This will not only cause a misfire but also overheating.

I have no heating issues so thats good lol. I'm sure my exhaust could use some help but I'm not trying to put more money into this car. Just doing simple maintains to keep it running. It only gets driven hard 1-3 days out of the week. The rest of the time I'm driving my Masi to work and home and thats about it.

When my cats go on the bimmer. I'll probably just get the catless headers in replacement. But DIYing headers doesn't look very fun.

So I got lazy and didn't change them yet. I will soon... and I'll post pics lol.

here they are. My old spark plugs from when I fist installed the supercharger. They have about 45k miles on them.

definitely should use colder plugs with the increase in cylinder pressure/temperature.

ur gonna need to do plugs more often than you think with that jump in power. new n54 engines with twin turbo require plug changes every 50,000 miles or so i believe... as opposed to the n52 (naturally aspirated) recommend every 100,000.

Originally Posted by chansta

definitely should use colder plugs with the increase in cylinder pressure/temperature.

ur gonna need to do plugs more often than you think with that jump in power. new n54 engines with twin turbo require plug changes every 50,000 miles or so i believe... as opposed to the n52 (naturally aspirated) recommend every 100,000.

I know, I want to do one step colder plugs and I will eventually. But I got more OEM spec NGKs for free so I put them in.

wouldn't it be better to use ngk iridium spark plugs ?

OMG running stock plugs? Would have swap them long time ago and used NGK copper resistor less plugs and one step colder as well. Gap around .27

Originally Posted by TrippinBimmer

OMG running stock plugs? Would have swap them long time ago and used NGK copper resistor less plugs and one step colder as well. Gap around .27

Yup I would of also. But I figured I'll use stock since they were free and the other ones worked fine as well.

Engine won't be happy

Originally Posted by MalibuMafiaV

Yup I would of also. But I figured I'll use stock since they were free and the other ones worked fine as well.

You realize that we're going to hassle you appropriately until you put in the right plugs...

Sell your new ones to another fester. I'm sure somebody needs them.

Originally Posted by TrippinBimmer

Engine won't be happy

Engines fine. You know E46Mango right?. Ask him how the internals of my engine look. Best looking engine around.

Originally Posted by marlin1881

You realize that we're going to hassle you appropriately until you put in the right plugs...

Sell your new ones to another fester. I'm sure somebody needs them.

New ones are aleady in it's to late

p.s. You guys do know the stage 1 kits come with OEM spark plugs right?. Granted I am far past stage 1 I'm just making a statement that the OEM plugs can take a beating and don't do that bad.

Those really don't look as terrible as I was expecting. Did that clear up your miss issue?

Originally Posted by MalibuMafiaV

Engines fine. You know E46Mango right?. Ask him how the internals of my engine look. Best looking engine around.



New ones are aleady in it's to late

p.s. You guys do know the stage 1 kits come with OEM spark plugs right?. Granted I am far past stage 1 I'm just making a statement that the OEM plugs can take a beating and don't do that bad.

Just for hahas, did you by any chance measure the gaps on those used plugs, and compare them to whatever it was when you first installed them ? On FI engines, increased combustion chamber pressures sometimes closes up the gaps a little....

Compared to a single electrode spark plug the multi-tipped spark plugs don't do any better performance wise. They have multiple electrodes because OEMs want long lasting plugs.

With multi-tipped spark plugs the firing of the electrodes alternate so the point of lowest resistance always gets the spark jump. Now as it starts to wear the shortest electrode distance is where the spark will jump from. So when the end of life of the plug comes about the car will start to miss fire as all 4 electrodes are worn. Remember that this design spark plug is designed so the center electrode fires from the side edge. once that is worn the plug becomes harder to fire and replacement is necessary.

I chose to run regular copper V grove NGK 4644 spark plugs over the BKR7EIX. I have had luck with the 4644's with over 400whp and they are cheap.

Not all kits recommend running stock plugs when FI. Maybe on the VF stage one kit but its very low boost compare to others.

MangoE46 took the head off and look inside the motor?

Originally Posted by nivo

I chose to run regular copper V grove NGK 4644 spark plugs over the BKR7EIX. I have had luck with the 4644's with over 400whp and they are cheap.

X2. And it's only 9bux to replace everytime...

Originally Posted by Fast Bob

Just for hahas, did you by any chance measure the gaps on those used plugs, and compare them to whatever it was when you first installed them ? On FI engines, increased combustion chamber pressures sometimes closes up the gaps a little....

No I didn't unfortunately.

Originally Posted by nivo

Compared to a single electrode spark plug the multi-tipped spark plugs don't do any better performance wise. They have multiple electrodes because OEMs want long lasting plugs.

With multi-tipped spark plugs the firing of the electrodes alternate so the point of lowest resistance always gets the spark jump. Now as it starts to wear the shortest electrode distance is where the spark will jump from. So when the end of life of the plug comes about the car will start to miss fire as all 4 electrodes are worn. Remember that this design spark plug is designed so the center electrode fires from the side edge. once that is worn the plug becomes harder to fire and replacement is necessary.

I chose to run regular copper V grove NGK 4644 spark plugs over the BKR7EIX. I have had luck with the 4644's with over 400whp and they are cheap.

Good to know. I'll check those out, thanks Nivo.