Insufficient information is given - but it could possibly be a sticking valve lifter that quiets down and the noise goes away after the engine is warm and the oil is circulating.
The fuel injectors make the ticking noise you hear at startup, especially when the engine is cold (colder temperatures).
Oil slow getting to the head
I think it needs a nose job, a.k.a., rhinoplasty.
It could be a sticking hydraulic lifter or valves that are slightly out of adjustment.
Could be a weak oil pump. The reason it is ticking is that the oil is not flowing to the lifters when it's cold. It's not that big of a deal.
I'm in the same boat: Try reading all pages on these links: http://townhall-talk.edmunds.com/direct/view/.f15850c/0 http://forums.automobilemag.com/70/6248778/toyota/2002-toyota-highlander-problems/index.html this one has photos how to do the repair: http://www.tundrasolutions.com/forums/highlander/32217-heater-quit-sort-of/
For a 2007 Toyota Highlander, the recommended oil weight is typically 5W-30. However, if you are operating in extremely cold temperatures, you might consider 0W-20 for better cold-start performance. Always check your owner's manual for the specific recommendations for your engine type, as some variants may have different requirements.
The ticking noise in a 1995 Aspire when cold is often due to the lifters or valves not getting enough oil circulation as the engine starts. When the engine warms up, the oil thins and flows more easily, reducing or eliminating the noise. Additionally, it could be related to exhaust leaks or components like the timing belt tensioner. Regular maintenance, including oil changes, can help minimize such noises.
The ticking sound you are hearing from the rover when it's cold is likely due to the metal components expanding as they warm up. This expansion can cause parts to move slightly, creating the ticking noise. It is a normal phenomenon and should not cause concern as long as the sound goes away once the rover warms up.
a "knocking" noise could be your lifters. and the ticking when accelerating and letting out of the gas is the same thing. check your oil and if it's full then you may need to think about either having them adjusted, or getting new ones. depending on what you have depends on whether or not you wanna sell it
It can depend on whether or not your area is subject to extreme heat or cold conditions but the usually recommended oil is SAE 10W-30.
Hereford or a Highlander