Signs of old plug and o2 sensor

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ericem
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Signs of old plug and o2 sensor

Post by ericem »

Hey guys, so recently did my spark plugs and replaced the o2 sensor. Why does one plug has rust around it? I am wondering if using the v power plugs are a bad idea. I think next week I might try just normal copper plugs and gap them at .28 instead of .38.

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What I am noticing is acceleration is very laggy and unresponsive. Actually its pretty slow sometimes. Car does not seem to misfire, or have trouble starting (instant).

Oh and here is what the o2 sensor looks like. Is this normal?

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1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
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Legacy777
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Post by Legacy777 »

You probably are getting a little blow by on that plug.

Which cylinder was it?
Josh

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ericem
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Post by ericem »

number 1 I think. Front passenger side. Closest to the rad.
1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
2007 Subaru Legacy GT :)
vrg3
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Post by vrg3 »

It could also just be caused by improper spark plug boot fit. What kind of plug wires are you using? Are you using dielectric grease to protect the connection?
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
ericem
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Post by ericem »

there oem wires and no i am not using grease.
1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
2007 Subaru Legacy GT :)
vrg3
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Post by vrg3 »

You should. If that is rust it could very well be because rainwater is getting into the spark plug well.

Get some dielectric grease (also called "tuneup grease") and smear a little into each spark plug boot. I also usually coat any rubber surface on the boot that touches the engine to help it seal there too.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
ericem
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Post by ericem »

ok cool ill give it a shot. I am still wondering if i should just get some normal copper plugs and gap them to like .28. I still dont feel the acceleration is there.
1993 Subaru Legacy L AWD Wagon R.I.P
1994 Subaru Legacy SS R.I.P :(
2004 Nissan Titan LE 4X4
2007 Subaru Legacy GT :)
jefferson
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Post by jefferson »

Josh nailed another one. You had a bad seal on that plug that was allowing combustion pressure past. Good time to replace it.

Jeff
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suba
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Post by suba »

That plug (front on drivers side) seems to have a tendency to get rusty, mine does it as well. My theory on it is that because of the battery being in the way it's hard to get the boot seated all the way on the plug so it doesn't seal against the engine as well so water can seep in and cause rust.
90 Legacy L AWD 5mt
Formerly of the USMB but moved from an RX to a Legacy
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