So here’s a stinker that apparently has my mechanic puzzled. A few days ago I brought in my 2002 Jetta wagon in for a headlamp bulb change and a oil change. I pull out, but by the time I get home the check engine light is on. The manual says it’s an emissions issue. I plan to make a garage visit on Thursday. they call me and say that they have my hubcaps…for some reason. OK, well, the next day, I am accelerating to get onto the highway, and suddenly, there is a big power drop and shudder. I pull over, call AAA and they take me in to the garage where I got the oil change. Today, they say that a number of the spark plugs were out, but that it was strange because the corrosion made it clear that they had not been disturbed or pulled off in any way. They said that the spark plugs accounted for all of the car’s symptoms. But we could not figure out how multiple spark plugs came out. Any ideas?
I’m leaning toward haunting.
Who have you pissed off lately or do you have a few teens on your block who don’t have enough homework to do?
If someone were to remove my sparkplugs and reinstall them, I seriously doubt if I could tell by looking at the plugs. I doubt of anyone else could either.
When was the last time you replaced the plugs?
Did you do it yourself, have a friend do it, or was ait done by a shop?
If you did it yourself, how did you torque them?
How many miles are on the car?
Is the car fixed now?
And lastly, why did they have your hubcaps?
I know, it’s a puzzler. (haha). Plugs had been there a while…I can’t remember ever having them changed, but to be fair, I’m not the only one to take the car into the shop when it is sick. At least 2 years and it would have been done by a mechanic. Appx. 60K miles. The car is due to be fixed tomorrow. It took forever to replace the bulb and get an oil change, 75 minutes or so. When I asked them if they were waiting for the components of a head light for a jetta to coalesce out of the ejecta of supernovae (not really), they said that to reach the lights they had to remove the battery(?) and take off some pieces to get in there. The charge for the whole service was minimal, under $45, so it did not seem they were ripping me off. I have no idea why they had the hubcaps. Naked rubber fetish? 
They weren’t rotating the tires or anything.
If they have the plugs, I’ll look at the threads to see if they are stripped. But it’s weird.
@rjblaskiewicz you need to explain “a number of the spark plugs were out” . . .
Do you mean that the plugs blew out?
Honestly I am only working with what I was told. Is there a pressure that might propel them out of their little spark plug homes?
You betcha there’s pressure! The gas and air get sparked by the spark plugs (get it?) and a big boom occurs under the plug and on top of the piston. That’s what makes your car go. As mentioned previously, check to see if the threads are stripped…on the car’s cylinder head (the place where the plugs screw in). The plugs are steel and much stronger than the aluminum head. If the head was stripped, the new plugs wouldn’t screw in easy and they won’t stay in. The head can be fixed with a gizmo called a Heli-Coil, on the car, if done by a careful mechanic. If the plugs weren’t torqued properly, they can back out over time but if they’ve never been replaced, that is very unlikely.
I was going to say that I suppose that setting off explosions might put your plugs under pressure.
I just never considered pressure in that direction. Yeah. Total noob. I’ll ask them about the head when I go visit my car in the shop this afternoon.
Thanks all very much. I appreciate your expertise and willingness to help! It’s quite generous.
Are you sure he said spark plugs and not spark plug wires? spark plug wires are pulled off and pushed on to the spark plugs where spark plugs are screwed into the head.
This would make more sense, especially if the spark plugs are in holes in the valve cover and the spark plug wires seal the tops of the holes. The if your PCV valve was clogged up and you have a slight leak in your valve cover o rings, then pressure would build up under the spark plug terminals and blow them off.
Oh yeah, head light bulbs, one is usually real easy to change, the other is hidden behind the battery and sometimes other stuff too and is always hard to change. Of course, its the hard one that always blows.