Spark plug blow out..

3.2Carrera · 3.2Carrera's Garage

I was driving my car home from work today and I noticed it started to sound like a lawn mower (turned the car off instantly). I pulled over and noticed one of my plug wires was sticking out,i went to pull it and the wire had broken off from the top. There seems to be no damage to the plug thread, which makes me think the head should be fine. What do you guys think? Could i have damaged my motor? Was the spark plug not tightened enough and possible blew out..

I am going to replace all wires and plugs

3.2Carrera · 3.2Carrera's Garage

I also noticed that the tip of the plug was stock in the wire, like it had unscrewed. Take a look at the photos. Thanks

Rouxzy · 07-20-2009, 08:47 PM

By the looks of the threads it seems the plug has been loose and rattled itself out of the socket. The reason for the motor sounding funky is because it was only running on 5 cylinders when the plug came out. Make sure to torque the plugs done when replacing.
Tom

rnln · 07-20-2009, 08:55 PM

Hope your head's threads are fine. This is the second time I heard this. The first time I heard was the plug was "shot out" and dent the hood (different car). Head's thread damage.
Good luck.

3.2Carrera · 3.2Carrera's Garage

Quote:

Originally Posted by rnln

The first time I heard was the plug was "shot out" and dent the hood (different car). Head's thread damage.
Good luck.

oo man that would have been really bad, mine seemed to just rattle its self out

DRACO A5OG · DRACO A5OG's Garage

Yeah re=torque all plugs properly.

Also I noticed you are missing the cap at the other end, is it in the wire rubber plug?

You should always check plug's caps are tight. some times they come loose to.

I highly recommend copper plugs Bosch or NGK's. RnlN and I both switched back to old School Coppers and we are very happy. We put in NGKs

3.2Carrera · 3.2Carrera's Garage

Quote:

Originally Posted by DRACO A5OG

Also I noticed you are missing the cap at the other end, is it in the wire rubber plug?

You should always check plug's caps are tight. some times they come loose to.

Ya the cap of the plug unscrewed its-self, and is stuck in the plug wire

Hugh R · 07-20-2009, 09:37 PM

Threads look kind of chewed up. I'd consider a thread chasing tool. Very dangerous if you don't know what you're doing. I cross threaded a plug once and ended up pulling the motor to get a straight shot at it. My brother, a Jet Propulsion Laboratory machinist said "Do you want to eff it up or do you want me to fix it". Wise words, he retapped it and it was magic what he was doing in terms of gauging the hole and getting back the threads.

Don't just try and run another spark plug into it, you may well make it worse.

DRACO A5OG · DRACO A5OG's Garage

Quote:

Originally Posted by 3.2Carrera

Ya the cap of the plug unscrewed its-self, and is stuck in the plug wire

Wow, so were the NGKs or Bosch?

Luckily you can use the plug to screw it back in the pull it out.

3.2Carrera · 3.2Carrera's Garage

they were bosch

DRACO A5OG · DRACO A5OG's Garage

Oh I see, I noticed NGK's have that issue too. I guess it is a common thing. That sucks.

3.2Carrera · 3.2Carrera's Garage

how do i tell if the head thread is damaged??

DRACO A5OG · DRACO A5OG's Garage

Try to place a new plug in there. Making certain it is straight and hand thread it in. It should be pretty smooth, then torque to 14-18 pounds per spec.

If it is tough from the beginning then you may have a stripped thread.

I dought it, it just may have not been properly torqued in the first place.

I always re-check the torque when cold, because the metal tends to shrink when cold ergo loosen the plug.

3.2Carrera · 3.2Carrera's Garage

Well i am not going to be driving the car for a couple of day's

, will make sure to check if the plug screw's in smooth, Thanks for all the help

DRACO A5OG · DRACO A5OG's Garage

No Problem Brother,

Hey, I visit my Mom in Tarzana alot so if you need a 2nd opinion, let me know and I can stop by to give you fresh eyes on it.

Break a Leg,

Jim

BTW, your plug does not look like it was stripped in.

kodioneill · kodioneill's Garage

Take off the valve cover and use an inspection mirror to check the threads.

warment · 07-21-2009, 08:07 AM

Looks like you are fine. I blew out a plug in my supercharged 2000 Mustang GT a few years back. My head and spark plug threads were stripped.

I bought a rethread/insert kit and made the fix. I have had no problems at all since then. The kit was nice. It came with nice directions, multiple inserts, a swedge tool and a vacuum attachment to suck out drilled metal bits. It also came with an aluminum spacer to prevent the drill bit from hitting into the piston.

3.2Carrera · 3.2Carrera's Garage

Quote:

Originally Posted by DRACO A5OG

Hey, I visit my Mom in Tarzana alot so if you need a 2nd opinion, let me know and I can stop by to give you fresh eyes on it.

BTW, your plug does not look like it was stripped in.

Great Thanks Jim, send me an email next time you will be around my area, joeybrauer@yahoo.com, would like to have a second Porsche opinion...

Flat6pac · 07-21-2009, 10:04 AM

Just a thought, only the top thread will be distorted, if nothing else, grind a bevel on the plug on a grinder and a little ppressure and you should thread. You just have to get past the top thread.
Bruce

Walt Fricke · 07-21-2009, 12:47 PM

If a well lubricated new plug won't just screw in, an old plug with good threads can serve as a mild thread chaser.

Use a hacksaw to cut 2-4 vertical slots in the threads at the tip end, clean up a bit with one of those tapered edge small files from the kind of set we all should have, grease it to catch any small bits, and gingerly insert it. Turn just enough to clean the first head threads, and remove.

Walt Fricke