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Discussion Starter · #1 ·
2002 eclipse gt missing

My eclipse started missing really bad on my way home from work about a year ago. Pulled over and got it trailered home. Replaced cap, rotor, plugs, and wires then it drove just like normal for about 12 miles. then it started missing again. When I did plugs cylinder number 5 or 6 (can't remember) was very oily, but that cylinder still had compression. could my spark plug/valve cover seals cause a miss from leaking oil? went to go fire it up the other day just to run it, even tho it had a miss. It would not fire and killed the battery. Just posting this here to confirm my plug seal idea? or any other input would be good. getting a couple of days off of college and work to turn some wrenches on this pos.
 

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2001 Spyder GT. Koni adjustable shocks. ST sway bar.17X8.5 rims. LED headlights.
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Yes. This can be an issue. ...J.D.
 

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If there is an oil leak into the plug area it only stands to reason this would weaken the plugs efficiency, hence a weaker spark. The best scenario would be if it were the #6 plug so you don't have to tear down too much. Going with your theory try replacing the seals on the front side and pray this solves your problem. If not, then you will have to do the other side of the block also. I.m trying to wrap my head around how oil is causing a misfire. Generally, a plug that is saturated with oil is because the piston rings are not going their job.
 

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2001 Spyder GT. Koni adjustable shocks. ST sway bar.17X8.5 rims. LED headlights.
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Mine is up to 143,000 miles. My experiences owning my V-6 for some 17 years is that the cap and rotor last about 60k miles. By the time you need plugs [100k] the cam boxes usually need re-sealing, so you might as well do them at the same time, You have to pull the upper manifold to change plugs and wires. That is the way I would do it if I had to do it over. Just this month I finally cleaned my EGR ports. I think if I were to do that, in retrospect, I would do it when I had the upper manifold off as well. I did not know the car well enough to be that efficient, but in looking back that is how I would do it if I knew then, what I know now. BTW: I am running on my 3rd. cap and rotor set. ...J.D.
 

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Discussion Starter · #5 ·
If there is an oil leak into the plug area it only stands to reason this would weaken the plugs efficiency, hence a weaker spark. The best scenario would be if it were the #6 plug so you don't have to tear down too much. Going with your theory try replacing the seals on the front side and pray this solves your problem. If not, then you will have to do the other side of the block also. I.m trying to wrap my head around how oil is causing a misfire. Generally, a plug that is saturated with oil is because the piston rings are not going their job.
Yeah, that's what I'm afraid of, the plug was very oily even up on the threads, so that's why I thing its the valve gasket, if not it looks like I'm putting it on FB with a blown engine. and I did do all the plugs, took the manifold off and everything. i mainy work on 88-98 chevy trucks, they have a v v bad cap and rotor problem. They need replaced before 10k miles
 

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Discussion Starter · #6 ·
Mine is up to 143,000 miles. My experiences owning my V-6 for some 17 years is that the cap and rotor last about 60k miles. By the time you need plugs [100k] the cam boxes usually need re-sealing, so you might as well do them at the same time, You have to pull the upper manifold to change plugs and wires. That is the way I would do it if I had to do it over. Just this month I finally cleaned my EGR ports. I think if I were to do that, in retrospect, I would do it when I had the upper manifold off as well. I did not know the car well enough to be that efficient, but in looking back that is how I would do it if I knew then, what I know now. BTW: I am running on my 3rd. cap and rotor set. ...J.D.
Yeah, but the sound of it sounds like a spark problem, not a compression problem.
 

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2001 Spyder GT. Koni adjustable shocks. ST sway bar.17X8.5 rims. LED headlights.
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Yeah, but the sound of it sounds like a spark problem, not a compression problem.
YES...It IS a spark problem. The oil on the plugs is not from the compression chamber. It is oil leaking around the tubes the spark plugs mount in. It partially shorts out the plug because the oil grounds out the plug wire. Replace the spark plug tube seals and put new plugs in it. This is a known problem on the V-6 engines. I changed mine along with the cam box gaskets when the plugs were changed last time. ...J.D.
 

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Discussion Starter · #8 ·
YES...It IS a spark problem. The oil on the plugs is not from the compression chamber. It is oil leaking around the tubes the spark plugs mount in. It partially shorts out the plug because the oil grounds out the plug wire. Replace the spark plug tube seals and put new plugs in it. This is a known problem on the V-6 engines. I changed mine along with the cam box gaskets when the plugs were changed last time. ...J.D.
will keep you updated, pulling the intake tonight and slapping valves and valve seals in her, going to see if that fixes anything. Going to do another compression check on her tonight.
 

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Discussion Starter · #9 ·
YES...It IS a spark problem. The oil on the plugs is not from the compression chamber. It is oil leaking around the tubes the spark plugs mount in. It partially shorts out the plug because the oil grounds out the plug wire. Replace the spark plug tube seals and put new plugs in it. This is a known problem on the V-6 engines. I changed mine along with the cam box gaskets when the plugs were changed last time. ...J.D.
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electrode looks dry to me, there still may be hope the rings arent bad lmao.
 

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You're really replacing the valves and the valve seals? Or do you mean the valve cover gaskets and spark plug tube seals? I doubt your problem is your valves and valve seals, unless you've also got poor compression. That's an awful lot of oil to be leaking from the valve seals, IMHO. I think it's more likely the spark plug tube was full of oil and it ran down the spark plugs threads when you "pulled the plug".
 

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2001 Spyder GT. Koni adjustable shocks. ST sway bar.17X8.5 rims. LED headlights.
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This is a common problem with these. The old school Chysler Hemi's of the 1950's used to have the same problem. When they get older the seals on the lower part of the spark plug tubes harden from heat and start to leak [been there, done that]. If you have it as far apart as you indicate, you will obviously replace those seals anyhow. Mine was misfiring before I did the reseal and replaced what were almost new plugs. Keep us posted. ...J.D.
 

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Discussion Starter · #14 ·
As of right now, I have crank, but doesn’t run. It’s almost 2 in the morning. And I’ve been working out in the snow. Im fucking done for tonight.
 

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As of right now, I have crank, but doesn’t run. It’s almost 2 in the morning. And I’ve been working out in the snow. Im fucking done for tonight.
WOW ! You are a better man than I am !. Hope this solves your problem. Get some rest. ...J.D.
 

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Totally off the subject... I notice on your avatar that your front bumper lip is split. There is a very easy fix for that. Get yourself a piece of styrofoam and shape it so it fits inside the small section of the bumper.
Get a rubber bumper repair kit from your local auto store.. You will need to make a grove where the crack is and fill it with the rubber kit... Sand it to perfection and then paint it black like this....
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Discussion Starter · #17 ·
Totally off the subject... I notice on your avatar that your front bumper lip is split. There is a very easy fix for that. Get yourself a piece of styrofoam and shape it so it fits inside the small section of the bumper.
Get a rubber bumper repair kit from your local auto store.. You will need to make a grove where the crack is and fill it with the rubber kit... Sand it to perfection and then paint it black like this....
View attachment 44491
Damn, that would look badass as hell, never woulda thought of that. Second it gets on the road that’ll be the first thing I do!
 

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2001 Spyder GT. Koni adjustable shocks. ST sway bar.17X8.5 rims. LED headlights.
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First thing I would do would be to put a OBD2 scan tool on it and see what is going on inside. ...J.D.
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