I just paid off my truck a couple of months ago and hit 153k miles and this is my little story.

I was driving along and I heard this popping sound and thought it was another car and then I got on the gas and I heard it again and thougth "WTF?"
My first thought was I'd blown an exhaust gasket since that is what it sounded like and then I slowed down at a light and blue smoke starting coming from the wheel well and under the hood and I was thinking the motor had blown and fortunatly I was only a mile from my mechanic that sponsored my Eclipse (and handled some maintenance on my Toyota) so I pulled into his shop with the engine blowing smoke,popping and missing like crazy.
The only thing that kept me thinking the engine hadn't blown was the fact that the temp guage never moved.

We look under the hood and on the right side it looked bad with oil all over the place but we got a good look with a mirror and saw no oil coming from the block but was actually shooting out of the 2nd spark plug hole from the front so that made me feel a little better and pulled the coil off ands saw one of the oil seals was tore up and the spark plug had blown out but still screwed back in fine so that was a good thing.

The diagnosis was the coil pack apparently got a short and tore up one of the seals thus dripping oil down into the plug well and most likely lubed the plug threads till it vibrated itself loose and then blew out throwing oil all over the place.

It's all fixed now and they also removed the valve cover and checked out things underneath (I was concerned about sludge buildup) and it all looked good so they buttoned it all up with new seals and gaskets and a new coil pack and plug and will be picking it up in a little bit.

So,just a minor glitch and a huge relief after thinking the worst.

 

ive had that happen in a uhaul before lol, - the oil.

 

You're not the first person on here to have that happen to. Seems like its always a 5VZFE that it happens to, don't know why.

 

I found a really loose plug 2 different times in my 3.4, but never had 1 blow out, I guess I was just lucky I caught it before it unscrewed itself all the way! I wonder if it has to do with the low torque rating (like 165 in. lbs.).

 

it can happen form a bunch of things, stripped threads from hacks working on your truck, to high of a compression ratio, improper tq of spark plug resulting in ineffective use of crush washer.

not sure on these engines though why that would happen and or be a common thing, a heli-coil is often used to fix this, if the op actually had a plug blow out. this was more like jiggled out ;-)
i've personally seen and dealt with this before on other vehicles just not on the yotas yet!


way to keep a level head and get right to it man! you'd get some idiots who would just keep on trucking for a week!

 

Those earliest ones had the head gasket recall though.

 

weird glad it worked out better than it sounded....

 

those ford 4.6 are notorious for this.. and you must helli coil to fix it.. this is the first im hearing about the toyotas doing this

 

WRONG!

what about the head gaskets on earlier models??

 

I had this happen on a little honda one time at night by the ocean and it the spark plug wouldnt thread in , i found a rock on the side of the road and jimmy rigged to hold the plug in .

 

From what I've heard, and I may be wrong, but the 96's and early 97's had the head gasket recall.

It seems as though the 98's were the most trouble free IMO. lol

 

sorry to hear about this and glad it was nothing more major.

Guys what is a solution here then? Checking the torque of the plugs more frequently?

Every oil change? is that overkill?

 

I know I'll be checking mine more often but my problem resulted from the coil pack shorting and damaging the oil seal which caused the plug to become loose.

 

sorry to hear about it. I can't visualize how that would even affect one another, but I guess weirder things have happened.

 

the oil filled the sparkplug well up and the oil seeped down into the threads thus lubing them allowing the plug to vibrate loose hence the plug coming out which is definetly weird..

 

Yo,
Oil on the threads may have not been your issue at all read on brotha..
I had a finger pressure loose plug on the passenger side (middle cylinder) of my 99' SR5 3.4L engine.

Eventhough I was trying to be careful on the past plug installs..Unfortunatly, I think I was too light on the torque and used too much "anti sieze" for the plug threads. With these plugs it feels like the torque is good because of the crush washers..I thought I torqued it enough yet I wasent sure so I backed out the plug again... when I looked at it, sure enough the "Crush washer" was not even dented.

So, when I originally changed the plugs and the crush washers did not bite the plug hole enough. I discovered this by hearing a strange noise (pinging sound) so I then I proceded to check it out. I needed a plug change out anyway as I was past the 30K interval.

FINGER LOOSE... scary AND I saw discoloration on the valve cover from the "blow by" past the loose threads. No permanent damage however.. 170K... & Thank goodness. I think the crush washers for the new plugs made it feel like it was torqued enough...I feel now that an added & CAREFUL 1/4 to 1/2 turn is ok for the plugs because of these crush washers, I also only use a small drop of "anti sieze" for the plug threads... Again my bad.

 

I use a torque wrench to take out some of the guess work. Also make sure the threads are clean and lubricated with anti-seize to get the best torque on them.

 

Sounds like a torque wrench would be a good investment for you

 

Correct. Known as an "external flaw" this particular HG recall/issue involved some 96's and 97's and the flaw caused coolant to drip down the side of the block. It was on the passenger side but they would just replace both gaskets when the recall was active. I had my 96 done for free back when it was active.

Sorry for the threadjack. Now back to your regularly scheduled program.

 

Yeah, the dealership did a free recall on the rear coil springs and the head gaskets on my '97 back when I first bought it in '01. They told me the head gaskets needed to be done because my VIN# was within a batch of 4runners that (some of them) got their HGs installed upside down from the factory.