I changed the spark plugs on my '94 integra non-vtec, and 3 of the 4 were finger tight. I know that I did not install them this way. The new ones I installed I torqued down, went for a drive, and rechecked them, and 2 of them are loose again. When I say finger tight, I mean without rachet, just extension and spark plug socket.
What could cause this? Could it be a bigger problem?
Andrew
had the same problem, though, it was on a Mk4 Jetta turbo and it happened yesterday! I put them in just tight enough, drove it home, and under boost it would miss, like a coil went bad. Popped the hood, found out the coils were being pushed out by the loosened plugs... Tightened them back up, good as gold!
Bob at work drove his big mean Ford F150 from Minneapolis to Iowa to buy a John Deere tractor. His engine spit a few plugs out requiring head work at an Iowa dealership. He told me it was common.
Did you tighten them enough to compress the crush washer? It's usually 1/4 - 1/3 turn past snug.
When you say "torqued down" are you using a (reliable) torque wrench set to the actual factory torque spec? Are you using any type of anti-seize?
Bryce
Other than that, I got nothing. Sorry.
The F150 thing is totally different. The stupid 4.6 has like 1/3rd of a thread for plugs so it's stupid-common for them to blow the plugs straight out, threads and all. That is manufacturing dumbass decision that will not result in a recall.
As for all other cars, you have to actually crush the crush washer. Like Bryce says, find a torque spec and a torque wrench. On 99% of the cars I do plugs on I will re-tighten after the test drive for insurance anyways.
My old MX-3 blew a plug right out. When I popped the hood, it and the wire were lying on top of the manifold. Scared the crap out of me, thought I'd blown the freaking engine.
Do not use any kind of lubricant on the plugs.
The plugs were already lubed from the oil/gas mixture from the finger tight plugs pushing past them while driving, so yeah.
I do not own a torque wrench, but I went 1/4 to 1/3 of a turn past tight, I could feel the crush washer crush, then get really hard afterwards. I guess I'll just retighten them on a weekly basis, until they stop loosening. I'm doing this with the engine cold btw.
Andrew
Get a torque wrench. Srsly.
That's what I like about tapered seats, No gasket to worry about.
iceracer wrote:Do not use any kind of lubricant on the plugs.
I always use some degreaser on them before I put them back in, for safety.
