Strange sound

Just a hunch, but what weight oil are you using?

Sorry, but I'm automotively challenged... but I believe the oil weight is 5w/30?

Is that important?

It was probably not a great question to ask, but I asked anyway. :-) Reason: I've had cars which made the sound you describe for just a second or two until the oil got moving, especially when cold. 5w/30 is the right oil to use, but you never know what effect advertising might have on someone, so I asked.

If you open the hood and get close (without letting your tie dangle into the belts), can you get a more focused idea of where the sound's coming from? How long does it last? Does it vary with the RPMs? Change when you activate the compressor (turn on defroster)?

constant rate ticking.

- Consistently from the left-rear side of the engine compartment. (closest point to the driver)

- Mostly in cold weather. I drive a few blocks ticking goes away.

- If I increase engine revolution, the ticking rate remains constant, but usually goes away.

- Ticking rate is about 3-4 ticks per second.

-No change if defroster is on.

constant rate ticking.

- Consistently from the left-rear side of the engine compartment. (closest point to the driver)

- Mostly in cold weather. I drive a few blocks ticking goes away.

- If I increase engine revolution, the ticking rate remains constant, but usually goes away.

- Ticking rate is about 3-4 ticks per second.

-No change if defroster is on.

Sounds like a valve adjustment is in order, just did one on mine. I had similar problems and this fixed it. To tell exactly where the sound is coming from; get a 3' piece of vacuum or fuel line, stick one end in your ear and move the other end around the engine while it's running(kind of like a stethoscope). Watch out for moving objects! If the sound is coming from under the valve cover, most likely the problem is just an overdue valve adjustment.

Thank you so much. I'm actually going on a 500 mile trip tomorrow...is this something that can wait or should I rent a car? I don't want to be stuck in Detroit in freezing weather on the side of the road. What do you think?

Thank you so much. I'm actually going on a 500 mile trip tomorrow...is this something that can wait or should I rent a car? I don't want to be stuck in Detroit in freezing weather on the side of the road. What do you think?

The noise means there is too much of a gap between the valves and rocker arms, what you hear is the slack being taken up before the rocker arm contacts the valve. The main problems with this condition is that it hurts your engine performance and gas mileage. Since there's too much of a gap, that means the valves are not opening as much as they should and the heads are not taking in as much air/fuel or venting as much exhaust gasses as they should. Over an extended period of time, several months, this could lead to other problems. If this is a fairly new condition, the trip should be fine. When you're accelerating and you start hearing the noise, back off the accelerator a little, don't push it too hard for too long.

Thank you so much for your help. The trip went smoothly. I'll have the valves check when I return. Thanks again! :)

He mentioned the rate stays the same with an increase in engine speed. I would think this would point to something other than valves as I would expect the rate to change based on engine speed.

I have heard some clicking on my Tundra, especially when it is cold that sounds to me like a solenoid of some type. No idea if this could be a possibility here.

If its at a steady rate have a look for a noisey fuel pump.

perfectly normal on older toyotas cold start injector on my 2nd gens are real loud

I thought I had read that somewhere else..... I'm glad you confirmed. Thank you!