knocking noise right after start then goes away

[mtnagel]

When ever I start my car, I hear a knocking noise coming from the engine, but after it warms up (just a few minutes), the noise stops.

Any ideas as to what it could be?

[Jason Lesbirel]

Apparently it's a combination of valve tick and piston slap - neither are of much concern, unless the noise doesn't go away once the engine has warmed up.

[Toyguyz]

It could also be the oil you use versus the ambient temperature... Oil will thicken in cold weather so if your using say a straight 30 or 40 wt oil and it's cold it may take a little longer to get oil flowing through the engine...

[SC/TGrandAm]

yeah what they said, its normal so dont worry about it. Esp when its cold outside. :agree:

[USMCspy]

Are you using 5W30? If not you should use it in the winter as you oil will not move through the engine properly till it warms up. It's not a good thing, and can cause major engine problems. I use 5W30 in the winter and 10W30 in the summer. If it is extremely cold teens and below all the time you might even want 5W20 in the winter, though it is hard to find. As long as you don't burn oil the lighter the better

[mtnagel]

It has been very cold lately (it was -11F yesterday morning - tied a record low ) but today it "warmed" up to the 20's this morning and I did just notice it the last couple days.
:snowman:
I don't know what oil is in there, I just take it to oil change places, so I'm assuming they put in the right stuff, but it's been awhile since I had my last oil change.

[chasm31]

Just a suggestion. Change your own oil. I've changed mine since I got screwed just getting an oil change. Actually, I enjoy changing my own oil. You know what your puttin in it, easy non-time consuming job, not too dirty, and establishes a bond with your Pon-Yac. Also, I recommend using Lucas Heavy Duty Oil Stablizer. It some good stuff but you only need a 20% Lucas to oil ratio. Also, when changing oil, this is a great time to put that Lucas enjector cleaner in. I don't work for Lucas or part store, I just love it and proudly stand by it.

[Colin]

This is common for these engines , they pretty much all do it . I,ve even heard brand new cars do this . The pistons expand when they warm up and the noise will stop . As long as it goes away fairly soon after you start your car when cold it's O K . :D

[mtnagel]

Is there any reason why it would all of the sudden start to do this? I've had this car for over 3 years now.