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-   -   Exhaust leak from spark plug??? (

Tasteslikeink 06-22-2014 05:25 PM

Exhaust leak from spark plug???
I don't even know if that's possible but it's either the spark plug of the header gasket failed where it had loosened up which just so happens to be right above the #8 spark plug.

The plug isn't loose. It didn't blow out. I took it out to change it and had realized I ordered the wrong plugs and put it back in. Drove it around and then later that night I started it and it sounded like it had an exhaust leak. Brought it to my shop, found 2 loose bolts on my header and tightened them, then replaced all my plugs and wires. BUT THE SOUND WAS STILL THERE!!! Just under load this time. Not all the time. The spark plug wire boot had a light dusting of carbon. I still can't figure out if it's the header gasket, which is what I'm leaning towards, or the plug. It sucks that I have to be driving it to hear it other wise I'd smoke it out! Any suggestions? Also.. How do I find the right timesert or save a thread kit to buy? Thanks in advance. This thing is beating me down.

Tasteslikeink 06-22-2014 05:26 PM

I should add it's a 95 GT vert.

dawson1112 06-22-2014 05:30 PM

Any time the header bolts get loose it will blow the gasket out at that spot. Its almost a guarantee

Tasteslikeink 06-22-2014 05:35 PM

I figured as much. Same mechanic, new car.

mjr46 06-22-2014 10:19 PM

it's a header gasket, it's just that simple, replace it and be done with it..........

Maxwelhse 06-23-2014 12:14 AM

Replace it with a PERCY'S GASKET. Can't say enough good about them.

Wrenchman1 06-23-2014 06:53 AM

Just an added note, Don't reuse the hardware for the header, They are a one time deal.
Never remove hot sparkplugs, The threads can come with them in aluminum.
Not so much cast iron, still a good practice

Maxwelhse 06-23-2014 07:18 AM


Originally Posted by Wrenchman1 (Post 8401490)
Just an added note, Don't reuse the hardware for the header, They are a one time deal.

What? I have literally never heard of throwing away header bolts before unless they are corroded (like any other bolt). It seems like my ARP SS header bolt kit would have been marketed as "reusable" (because it is) just like my expensive gaskets.

HEAD bolts get tossed, sometimes.

Wrenchman1 06-24-2014 11:10 PM

torque to yeild
Way back when, I attended a GM motor school, We were instructed that any bolt that has a torque spec , is a one time use, Due to the fact that all bolts are an interference fit.
Due to harmonic vibration, They can loosen or not torque correctly.
There was also a tech article written up in one of the mags a few years ago.

bluebeastsrt 06-24-2014 11:15 PM

Well I've never been to any classes but I've been reusing header bolts for ever. I recently put headers on my 2011 Camaro ss and the company that made the headers recomended using the stock manifold bolts to attach the headers. No exhaust leaks on that install. The only bolts that are one time use in my book are head bolts.

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