Foo - Sparkplug Problems.......

My neighbor has an older Maxima with a V-6 that has a plug that neither he nor the dealer can seem to get out. He is afraid that anything drastic will mean removing the head and a big bill to go along with it.

Has anybody ever had this problem and what did you do about it? The car is starting to run rough and he wants to change that plug to see if that is the issue.

Any thoughts, including any boards that might provide assistance, would be greatly appreciated.

Thanks again.........

To avoid removing the head, you have to disassemble the car. (Kidding)

Have they tried accessing it via the wheelwell?

Have they tried accessing it via the wheelwell?Sounds like it's more of an "it's stuck" issue than an "it's inaccessible" issue.

Liquid Wrench and a breaker bar!

what year?
I assume it is one of the back three, and you can't get a wrench on it?

Try PB-Blaster down the spark-plug hole. I've seen it free up rusty bolts so corroded, the threads crumbled in your hands once it was free.

On the plus side, if you pull the heads, and while you're at it do a valve job, the engine life expectancy will go way up. :D

Hold the spark plug still and do donuts?

Thanks for the replies, but..............

It is a 2000 model and both the owner and shop can get a wrench on it, they just can't get the thing to turn. It is a transverse mounted v-6 and I think the problem plug is in the vee. My friend has tried using a breaker bar and still nothing. Apparently the plug has become one with the head and he is trying to keep from having a huge repair bill from pulling the head, having it torn out and then re-threaded. He implied that the shop may not have used an anti-sieze compound on the threads but that is conjecture on his part.

I think he said that he has about 360k on the engine but I am not positive, however in any event, he has gotten his money's worth out of the car.

I have even gone so far as to register at a Nissan forum but I can't yet post a question for some reason but I will try again this afternoon.

Thanks again for the help.

I don't have any spark plugs in my truck, so I can't offer any help.

Thanks for the replies, but..............
Apparently the plug has become one with the head...

And you call yourself a cyclist?? Everyone knows you have to use grease. :rolleyes:












:p

In short, he's screwed.
I would agree that the plug and head are now one, it's called gauling. They are pretty much welded together. Removing the plug will remove athe aluminium of the head that the plug is screwed in to.
The head will most likely be toast if that happens. The head may be able to be Heli-coiled, but doing that to a spark plug, with out removing the head, means metal shavings in the cylinder. Which is bad.
OR the plug will break, and the head is toast.
Can he get a new head from a junk yard?
Or sell the car quick.

Apparently the plug has become one with the head .

Read the Manual.

http://www.timlebon.com/zenmotorcycle.jpg

Thanks for the replies, but..............

It is a 2000 model and both the owner and shop can get a wrench on it, they just can't get the thing to turn. It is a transverse mounted v-6 and I think the problem plug is in the vee. My friend has tried using a breaker bar and still nothing. Apparently the plug has become one with the head and he is trying to keep from having a huge repair bill from pulling the head, having it torn out and then re-threaded. He implied that the shop may not have used an anti-sieze compound on the threads but that is conjecture on his part.

I think he said that he has about 360k on the engine but I am not positive, however in any event, he has gotten his money's worth out of the car.

I have even gone so far as to register at a Nissan forum but I can't yet post a question for some reason but I will try again this afternoon.

Thanks again for the help.

This is a bit extreme-sounding but it works well.

Fit socket and breaker-bar to sparkplug. Crank on it hard to TIGHTEN. You may hear a "pop", If you do, you're probably set and the thing will unscrew.

If no "pop", crank hard on the breaker bar in the tighten direction again, then whack the peak of the bend in the breaker bar with a large hammer. Now try unscrewing.

Failing that, spark plug socket, extension and impact wrench set to unscrew, but not a lot of force. Insert earplugs and pull the trigger on the impact wrench. Plan on being there a while. The vibration from the impact wrench will get it to move eventually.

+1 to the tightening trick.

The vehicles I used to wrench on in the USMC were Aluminum hulled, and used steel bolts. Crewpigs never used anti-seize, so EVERYTHING was always stuck. This trick works very well.

Worst case, just drop the ENTIRE SUBFRAME (I'm a little prone to go overboard for easy access :D) if the sucker breaks off....

Thanks for the 'tightening' idea. I will pass that along to my neighbor.

hm put 1 inch impact gun on it.. it should either remove the spark plug or remove a piece of the head along with it..

If the engine has 360,000 miles the plug has probably been changed a couple times before, I hope. It is a possibility that the plug was cross threaded when it was installed. With that many miles he is probably best to leave it in, because when the plug is removed it will take pieces of the head with it.

I once replaced a timing chain on a mid 90's maxima and the heads had to be removed to do that job. It was a huge PITA, and it cost a lot of money. If it was my car I would seriously think about how much money I am willing to spend before going any further.

On the plus side, if you pull the heads, and while you're at it do a valve job, the engine life expectancy will go way up. :D

...right up until the rings blow, but I'm not sure he'll have much of an alternative. Spark plugs should go on the same way as oil filters, just tight enough to keep a seal and no more. Hopefully the overtightening trick will work.

Here's what we did on a buddy's old Rover that has an aluminum head. Aluminum (head) will expand faster than steel (threads on sparkplug) when heated. On a cold engine, pop off the plug wire on the stuck plug, put your wrench on the plug while someone else starts the engine. After the engine is running on the remaining cylinders, start applying force to the wrench you have on the plug. Once the head starts to heat up, apply more force to the plug. Once it breaks free or turns slightly, shut off the engine and go about removing the plug.
That worked for us. May or may not work for you. Attempting this will certainly throw a CEL so be prepared for that.
Barring that and the impact suggestion above, looks like you'll be removing the head and taking it to a machine shop.
Good luck and let us know how it goes.

I do most of the wrenching on my own vehicles, but never encountered this problem. There have been many good suggestions posted here. Just keep applying torque to it. If the head comes off and goes to a shop they will also apply torque to the plug. The threads may get messed up, either you will do that or the shop will do that. Or the plug will come out once the proper amount of torque is applied. Putting a heli coil in a head is not that big a deal for a shop. Hope you get it out.

Sparkplug? What kind? (http://www.youtube.com/watch?v=cUhtv2XOolU)

As always, thanks for the replies.

Not sure what type of plugs he has in the car but he has always been very good about keeping things in good working order. Really surprised this has happened.

As for the heli-coil......he is trying to not spend that much money on a car with 360k miles on it and as such is out looking for a newer car.

Thanks again.

How about more about the symptom. "Running rough" is rarely fixed with a plug anymore. Hasn't Nissan been using platinum plugs in Maximas since the 80s? Pretty hard to wear out a platinum plug. It can happen, but not likely to fix his running problem.

Under what conditions does the problem happen? Lots of details here would help.

Spreggy,

Sorry for the lack of info. The car is running very rough, and he surmises is running on 5 cylinders and has little pick-up. He has been to the dealer but opted not to have them work on it, but I'm not sure why.

We live in a duplex but work very diifferent hours so we don't chat a lot but I will try this evening to ask how things are going.


Thanks agian.

OK. First, DO NOT USE A BREAKER BAR. Never use force with plugs. Never.

If the car has an aluminum block, it's likely seized. Chemically welded together. This is why you always use plenty of anti-seize compound. Just like aluminum spoke nipples!

So, PB blaster would be useless. (although it's the best stuff you can use on rusty bolts)

He may be screwed. Maybe not. But, I repeat, DO NOT USE A BREAKER BAR unless you just want to rip the threads out.

Oh, and Platinum plugs are crap. All of them. Especially Bosch +4s. They absolutely are are a reason for running rough. They lose their proper gap after about 25k-40k. Just like copper plugs. They also run hotter. I have used platinum plugs. I never will again. If a new car comes with them, I will swap them out first chance I get. Every mechanic I have talked to agrees. Especially about the Bosch.

sneefy,

My neighbor and the shop mechanic have both tried a breaker bar and neither was able to get the plug out. Apparently he has been going to the same shop for years and the mechanic often helps a lot for practically free and offers a lot of advice on how he can do things himself. He did say that the plug he can't get out.....now......was always hard to change.

He also tried tightening it a bit and then unscrewing it but that didn't work either.

I think he is simply going to run the car until it dies and buy another one.

Thanks again for all the suggestions.

Too bad. 360k is a good run, though...


sneefy,

My neighbor and the shop mechanic have both tried a breaker bar and neither was able to get the plug out. Apparently he has been going to the same shop for years and the mechanic often helps a lot for practically free and offers a lot of advice on how he can do things himself. He did say that the plug he can't get out.....now......was always hard to change.

He also tried tightening it a bit and then unscrewing it but that didn't work either.

I think he is simply going to run the car until it dies and buy another one.

Thanks again for all the suggestions.

Oh, and Platinum plugs are crap. All of them. Especially Bosch +4s. They absolutely are are a reason for running rough. They lose their proper gap after about 25k-40k. Just like copper plugs. They also run hotter. I have used platinum plugs. I never will again. If a new car comes with them, I will swap them out first chance I get. Every mechanic I have talked to agrees. Especially about the Bosch.yeah, platinum plugs are all about marketing and getting more money out of people. Mechanics love them because they can charge more and actually spend less work on them. Platinum plugs do last longer and are relatively more maintenance-free than copper-plugs. But they do have problems with running hot and the centre-core falling out. The +4s are the worse because there's no centre-electrode to catch the core. I've also seen a few with snapped centre insulators leading to the broken piece acting as a glow-plug and causing detonation and eventual headgasket failure. Hmmmm... I think I've got a picture somewhere...