Alaskan cold, Alaskan Tickity-Tic?

Well, for those of you "outside," as you're known in warmer parts of America, it's starting to cool down right quick here in Alaska's interior. A week ago, I toured Denali National Park with my Tacoma amid 65°F weather. This morning, as I started my truck amid the brisk 10°F darkness, not only did my battery groan after a couple of cranks, but after it finally turned over and warmed up to operating temperature, I walk around to the driver's side to get in, only to be stopped short by a distinct "Tickety-Tic" sound emanating from under the hood.

I pop the hood to inquire as to the nature of this new, intriguing sound to find that it's coming clearly from near my master break cylinder against the driver's side firewall. It sounds like a Timex watch, only louder. And bigger. And more metallic. Precisely like it's coming from a 5VZ-FE 3.4L V6.

"Tickety-tickety-tickety-tickety..." a couple of times a second.

I wonder, dearest friends, what it could be...any ideas out there where it's warmer?

I am – as always – in your debt.

 

valve tick.

the oil in your engine is too cold (yet) to get up to the top end of the engine and the ticking you hear is the valves opening and closing. This will eventually become a permanent sound even after the engine is warm due to wear on the valve train.

I just moved to Canada this summer and it is signature sound of cars that have been in Canadian winters! Mine doesn't do it yet and I plan to add a 125 watt oil heater that i leave plugged in all night long while the truck is parked. (there is a excellent thread on here with the mod that is needed: http://www.tacomaworld.com/forum/2nd-gen-tacomas/52827-oil-pan-heater-mod.html

The oil heater will keep the oil warm which will facilitate circulation in the engine when truck is started and thus prevent valvetrain wear.

my 2 cents.

 

Thanks, Sam, but I'm not so sure it was the valves. It was *really* localized at the master cylinder, and the assembly of gobbly-gook that resides right in front of it.

Besides, after owning small 4 cylinder engines most of my life, engines with overhead cams, I know when the valves are ticking. This wasn't that sound. And...this came from a heated-to-temp engine that I let warm up for more than 10 minutes.

This morning, with a temp down to 1°F, I didn't have the same sound. It magically went away, and the engine temp went I got in was 138°F.

The truck is modded for cold weather. Block/pan/battery, all ready to go. I just haven't plugged her in yet. Judging from the patience I needed this morning to start her up, I may well plug her in tonight.

Thanks for the suggestion though.

 

interesting. i am not sure what it is then. there are no moving/rotating parts at the master cylinder area. i would be anxious to figure out what it is soon in case something is going on.
be ready the next time it does happen. I would keep a 3 ft long rubber tube handy (a vacuum hose type of deal) to use as an engine stethoscope and pin point the source of the sound.
The other thing i could think of is the cold start injector - not sure which side the intake is located on your motor, but then the CS injectors should not be working if it was a warm engine.....
anyway keep us posted. very curious....

 

Thank you, Sam...I've heard about the three foot section of surgical tubing trick from Tom & Ray on Car Talk. I think I'll give it a try. The good news is that while it's gonna get *really* cold this winter (think -40-50below), if my truck poops out on me, it's only a mile or so to work. Still...who wants to walk a mile in those kinds of temperatures. Perhaps I should get used to it now, while the weather's rather balmy.

Cold Start Injector. Hmmm...never heard of them. I would guess that they too, would stop working after the truck warms.

Thanks, Sam.

 

Thanks everyone.

I've found the source of the loud clickety-click that happens when it's COLD. It's somewhere in the vacuum hose system. It emanates from the rear edge of the charcoal canister near a vapor pressure sensor, or something indicated on the diagram called "VSV for EVAP."

This clicking/tapping sound happens when it's cold out, Like ten below or colder, and when there's an active draw on the engine: when I take my foot off the accelerator pedal, I can hear the tapping go quiet. Accelerate again, and it immediately returns. It's loud enough to hear from inside. What does it mean?

 

Great info on a possible fix/help with the VSV ticking along with what the VSV is and does:
http://www.tacomaworld.com/forum/2nd-gen-tacomas/43632-ticking-engine-one-fix.html

I live in Florida and my '06 Tacoma has the normal quiet tick it sounds like all Tacomas have. However it's recently gotten cold here (like 40 degrees and cooler) and sometimes when I start my car in the morning I get a much worse/louder ticking than normal. Happens in P or D and speeds up/gets worse under acceleration. When I hit normal operating temp it sounds like it's back to its normal ticking. Not every morning it's 40 or below does it do it, but probably every 3rd or 4th morning... Have not tried the rubber washer VSV tick trick as just researching it all now. Luckily we don't deal with this cold stuff too often Not alarmed by my usual tick, but the extra loud when it's cold does/did have me a little worried. High octane gas did not help (didn't expect it to). Use Castrol Syntec blend oil as others have stated they get different ticking based on different oils. Anyway, see if the washers help, and hopefully this is just "normal"