CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Kknock knock knocking

hello fellow cartalk people. im not sure if you guys remember but i posted awhile back about knocking in my engine when cold and discovered i had put really thick oil in.



now it has been awhile and im worried ive damaged something in the engine. every morning when i start the car up and rev it you can hearin tick and knock and as you drive it goes away for the most part after the engine is warm and is sometimes audible. have i ruined the valves or soemthing something along those lines?



2001 kia sportage 4x4 about 90000 miles on it

Do you mean to tell us that after all this time, you did not drain the “really thick oil” and refill the crankcase with 10w-30, or 5w-20, or whatever is actually specified for this engine? Or, did you drain the thick oil and replace it in a timely manner?

If you did correct your mistake promptly and are still hearing knocking noises in the cold engine a few months later, then it is very likely that lubrication problems during the period of “thick oil” did do some damage to bearings. However, it is also possible that you are hearing piston slap. We can’t hear it, so this is difficult for us to identify.

Anyone can make a mistake, but to perpetuate that mistake by not correcting it in a timely fashion is something that I have a difficult time understanding. Please clarify the actual sequence of events for us.

oh sorry ya i replaced it about a week after i posted when i got the money. i had the oil changed and the noise improved but it still sounds bad and im not sure how to describe the noise but if its piston slap wouldnt i have had more problems arise by now?

While the noise of piston slap is definitely annoying, many mechanics believe that it is not harmful. I’m not sure that I agree with that assessment, but luckily, I have never had a car with piston slap. Why don’t you have an experienced mechanic listen to the noise?

i would prefer not to because 1. im a college student and cant afford to spare a hundred dollars for a diagnostic and i like to do as much as i can by myself or with help. plus not to many good independents around here

piston slap does go away after the engine warms up Have 3 acclaims all have had it for the last 70,000 km .Just do regular changes and use the right oil