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My 50 year old A4 runs fine, now that I know how to treat her.....but I have a question. I am running a set of new plugs in her, and all are fine....except #1 has a fine carbon film on it while the other three are clean. Why would that be? I'm thinking sticky valve, but would like your thoughts and what to do about it?
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If a valve were sticking you would likely have a misfire. Oil could be getting past a ring or valve guide, however. Can we have a look-see?Originally posted by quiesence65 View Post -
q, if you are running easy at low RPM's and or doing a bit of idling a darker #1 is not all that uncommon. As the engines in most cases tip back the #1 intake is the lowest on the intake manifold. Being the lowest with a updraft configuration it will draw the heavier bits of fuel (IE run a bit richer) as the better mixed and lighter stuff goes to the higher cylinders. Also the #1 does not get as good a coolant flow so the cylinder does wear a bit "worse" and often has a bit lower compression~no worries
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You could try leaning the idle a bit say 1/8 turn out at a time. If the engine starts a bit harder and takes another minute or two to get smooth when cold your about right.
Dave Neptune
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You could try reversing the order of the plugs on the off chance you were sold a funky spark plug.
TRUE GRITComment
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Thanks for all the insight.....Dave....I think you are on the money! I'm running pretty lean now, and the engine is running great....so won't mess too much with it! Thanks for the insight!!Comment
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