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What to do after an overdue oil change?

Hi gang,

I just ran my car 7000 miles beyond the scheduled oil change, and it has developed a quiet, clickety sound when idling. Beyond attentively listening to lectures about how I need to change my oil more frequently, what other steps can I do to proactively improve my car’s idling sound? Is it too much to ask to make my car hum again?

Thanks so much!

Clear up something, please.

Did you change your oil?

Or are you still 7K overdue?

That noise may very well be the valve lifters or tappets. If you’re lucky the noise will disappear when you do the oil and filter change.

It’s also possible the valve lash is due for adjustment.

What car?
Model year?
Mileage?

I hope you changed your oil. That’s where I would start.

Did you open the hood and check your oil level at any time ? How many miles total did you go between the oil changes?

Assuming the oil has been changed, I would cross my fingers and decrease the change interval to 3k for the next few changes to clean out any deposits or sludge that may have built up.

As I have a mind like a steel sieve, I keep a log book in the car to track fuel consumption and any service done to the car. It’s saved my bacon on more than one occasion.

Good luck,

Ed B.

what other steps can I do to proactively improve my car’s idling sound? -
That’s the least of your worries. Noisy fuel injectors can cause noise to. Just get back on schedule. Occasionally going over may not be a big deal depending on the conditions you do it. (lots of highway miles) Just be more careful.

That sound could be anything. It might not even be related to the oil not being changed. It might be something as simple as a loose heat shield.

Not knowing what type of car we’re talking about, how old it is, or how many miles it has on it, I won’t speculate further.

BTW, it was more important that you actually had ENOUGH motor oil left in the crank case. If there was enough, little aditional wear was done, assuming you go back to regular schedule, or better still, follow @edb1961 advice.

As is very common, we don’t know the total number of miles that the car was driven between oil changes, whether the oil level was ever checked during that period of time, and what type of driving conditions the car is normally subjected to.

If the car was driven in mostly highway situations, the damage may be minimal.
On the other hand, if there was a lot of short-trip local driving for thousands of miles, then there could be a significant accumulation of sludge in the engine.

In the absence of that information, my advice would be to follow edb1961’s advice, and to do a few 3k interval oil changes in order to–hopefully–clean out some of the sludge that may be sitting in the oil passages. Then, make sure that you fashion some kind of reminder sticker that you can paste on the upper left corner of the windshield in order to remind you of the mileage and date for the next oil change.

And, of course, make sure that you monitor the oil level at least every couple of weeks.