How to tell if spark plug needs changing
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Joined: Aug 2006
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From: south texas
2001 c240
How to tell if spark plug needs changing
I bought a 2001 c240 with 100k miles. I bought it at an lease return auction and do not know the history. I was wanting to change the plugs, but when I pulled out the first one, it looked pretty clean. It is a bosh platinum plug fr8dpp33 and has just a little fouling. The needle like electrode is clean. I was expecting to see it worn down or some fouling. I am thinking I should just leave it in.????
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From: Seattle WA
99 E320
http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html
the above photo chart will still be useful even if you're using platinum or
other space age exotics. if the gap is still within spec, or, you can adjust
to spec, then no need to replace the plug.
the above photo chart will still be useful even if you're using platinum or
other space age exotics. if the gap is still within spec, or, you can adjust
to spec, then no need to replace the plug.
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From: Huntington Beach, Ca.
'17 Jaguar XF
The recommended sparkplug change interval is 100K miles. Yes, they burn very clean, even at 100K miles they should look good. If you use the recommended plug again you can expect 100K miles before needing another change. No reason to take a chance with any other plug.
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From: Boston
'05 A4 1.8TQM6
Also the longer you leave it in, the more risk you run of having them seize in there. Some of the plugs I took off were hard enough at 93k miles. Some who have changed before that had plugs break on them while trying to remove because they were seized.
Its cheap insurance to keep the engine performing up to par. I'm sure the plugs will run fine at 100k but trying to get them out and replacing them may be a pain
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Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
) Every car manufacturer is extending maintenance intervals with new technology and cars are lasting longer than ever but old habits die slowly.......to each his own.
Thread Starter
Junior Member
Joined: Aug 2006
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From: south texas
2001 c240
Just finished changing the plugs 2.5 hours. Everything was going just fine until I was down to the last three on the driver side rear. There is not a whole lot of clearance to get in there. During the removal of the plug wire I put a little too much wrench on it and bam it popped off. I thought everything was ok until I could not get the socket on the plug. Then I realized that the ceramic top to the plug was inside the wire boot. 
I got a mirror and could see that some of the ceramic had fallen off and was wedged between the plug and the side wall not allowing a socket to go over it. It took about an hour and a half of fishing it with a coat hanger and moving it just enough to get it out of the way and allow the socket to catch. I crushed what was left in there while unscrewing the plug and paused about every four turns and vacuumed it out. A little nerve racking but everything turned out ok.
I was able to get it done, thanks to the help of the forum members posting. Recommend using a magnetic spark plug socket. It worked like a charm and I don't think I could have done it without one. Also, using the open end wrench to help take the wires off was a good tip.
I ended up putting in the Bosh 2 platinum.
Don't have a better pic of the nightmare.
I got a mirror and could see that some of the ceramic had fallen off and was wedged between the plug and the side wall not allowing a socket to go over it. It took about an hour and a half of fishing it with a coat hanger and moving it just enough to get it out of the way and allow the socket to catch. I crushed what was left in there while unscrewing the plug and paused about every four turns and vacuumed it out. A little nerve racking but everything turned out ok.
I was able to get it done, thanks to the help of the forum members posting. Recommend using a magnetic spark plug socket. It worked like a charm and I don't think I could have done it without one. Also, using the open end wrench to help take the wires off was a good tip.
I ended up putting in the Bosh 2 platinum.
Don't have a better pic of the nightmare.
Last edited by ragu; Dec 15, 2006 at 03:56 PM. Reason: additional info
