Seized MF#$%@&n spark plug!

[Heisenberg]

2006 R51 with about 180 000 (Canadian) km on it. I'm about to take it on a cross-country trip to BC and decided to do some preventative maintenance. On the list were spark plugs, which apparently were never changed (2nd owner). Five came out like butter. The last is seized, about 1/4 of the way out. Everything has been tried, PB blaster, soaking for several days, heat cycling etc. I even took it to the local dealer, whom I have a pretty good relationship with. They spent two more hours over three days; and only charged me $50 due to "no go" results! Any increased effort will result in a broken plug, and a 19 hour job to remove the head.

Some good news: The truck runs fine as is. No stumble at idle, no SES light, and fuel mileage is slightly improved over the 200 km I've driven since the service. Since I'm German my OCD is second guessing the situation and I'm somewhat reluctant to trust the vehicle on a major road trip.

Options listed in order of preference:

A) Turn off your OCD and drive the damn thing. You have CAA plus (AAA but further North) and the means of getting the fam home even if shit hits the fan.

B) Turn your OCD to 11 and shell out the big bucks. Get the head drilled out and tapped. Check up on the (so far quiet) timing chain guides while you're in there.

C) Replace the missus' '06 Passat wagon (250 000+ km) with something newer and more reliable. Unfortunately my Germanness is also a bit debt adverse, hence this is the least preferred option.

WWTNPD? (What would The Nissan Path Do?)

Thanks for your response,
H

[smj999smj]

I remember about 15 years ago I replaced plugs on a Mercury Villager (the Nissan Quest's sister) that still had the original, NGK copper core spark plugs in it (you could tell because it had the Motorcraft and NGK names on the plug), which had a recommended service interval of 30,000 miles. The vehicle ran pretty good...even on the original spark plugs with 148,000 miles on them! The electrodes were actually worn below the porcelain. If the copper core NGK's can last that long, just think how long your original, double platinum NGK's will last!

[eieio]

WWTNPD? (What would The Nissan Path Do?)

Thanks for your response,
H

That sucks!
I'm sitting here wondering what would cause that.
I'd be real hesitant to drive it with the plug 1/4 way out.
If it were to loosen on it's own due do vibration & compression pressure, it may damage the threads in the hole & the plug and blow out of the head.
Can it be retightened securely back in, or is it really stuck at this point?
If the plug cannot be re-tightened securely, it's going to have to be dealt with sooner or later.
I've repaired many plug holes in aluminum heads (Heli-Coil) without removing the head.
Is it one of the plugs where it may be accessible to do that?

[cleanthez]

I'd honestly run it back in and drive on with it.

[Heisenberg]

Thanks for the replies!
The plug is driver's side rear, near the firewall, so somewhat difficult to get at. It's completely seized, not going in or out. Judging by the excellent condition of the rest of the plugs (no corrosion at all) I'm almost certain it was cross threaded. The plug is not going anywhere, especially on its own.

Update: Looks like the dealer WAS able to get the plug (mostly?) back in place. The coil pack is now at the same level as the others. Option A is gaining traction...

H

[smj999smj]

That's what I would do. It's either that or "go or it" and risk opening up SPAM DO NOT CLICK's box!

[disallow]

I'd honestly run it back in and drive on with it.

+1 on this response. Its not worth it.

My Father in Law ran his Toyota van on copper core plugs for over 300k kms. Not that I recommend that, but you don't want to have to pull the head because of this issue.

[Heisenberg]

Yup, leaving in the morning. We'll be blazing right through the 'peg on our way to Brandon on the first day. Truck is not showing any issues and gas mileage is improved (5 out of 6 new plugs?). If you see a brown/beige R51 with a Yakima box and 4 bikes on the roof: Wave that's us

H