Cold start knock... Ideas?

I have a 2013 TRD sport 4x4 4.0l with 69,xxx on it. The last couple of days its started to tick or knock on warm up. Once it warms up the noise goes away. Oil change every 5k with Mobile 1 FS and Toyota filter. No leaks, no smoke and doesn't seem to be using any oil. Any ideas since I'm out of warranty now??

 

Do you live in an area with mostly mild winters, but temps drop somewhat drastically every once in a while? I do, and on those cold mornings my 4 cylinder makes some very light knocking for about 30-60 seconds after startup. Been that way for 100,000 miles never got any worse. Methinks piston slap, but those words evoke some contention on this forum for some reason. My vote is normal if you're suddenly getting colder than normal temps.

 

Yeah North Carolina, temps go from 70's to 20's in the same week.

 

NC & VA get to dance with the jet stream all winter and spring, so I hear ya on the temperature fluctuations.

 

Are you sure it's a bottom end knock? Might just be some valve noises. The lifters need oil in them to work properly. I wouldn't worry about it unless you hear it getting worse. Just keep driving it for another 200 thousand miles...

 

A "knock" and "tick" are two different things. Tacomas have solid lifters, so the tolerances will not be correct until the engine is warm. This will cause a "tick". Pretty normal. You could hear a knock until oil pressure comes up because the oil film between rod bearings has not been established yet. I hear the tick on cold mornings too, but any knock sound is gone in seconds.

 

Yeah, I'm not sure where it's coming from specifically but it sounds more like top end. And to me it sounds like more of a "knock" than a "tick." It's never made any noise like this since I bought it with 30k miles. Like I said this just started a couple days ago. I've also had it in much colder temperatures before with no noise.

 

Mine does this too. So bad that my girlfriend thought she broke my truck. I'd describe it as a deep toned tick. It only does it on cold mornings, and being in Florida the temp can fluctuate rapidly. Volume of the noise decreases almost instantly, and fully disappears once warm. I've heard it's common.

 

I had something similar going on..., though it was during milder temperatures. I would hear a rattle or knocking for a few seconds on first acceleration out of the driveway, then nothing. I also had an issue where 2 or 3 times in the last year the truck would have trouble turning over on the first try, but then would start right up. I'm not a mechanic and I have a warranty on my 2013 but couldn't get either reproduced at the dealer.

I ended up having them change the spark plugs on a hunch that they were overdue. They said they looked like they were the originals..., I have just under 80k on the truck, so way overdue.

Anyway..., could be totally unrelated but I haven't had either issue above since the plug change.

 

Thanks for the suggestion. However the plugs were replaced with NGK's less than 10k miles ago.

 

from what you guys are describing. it sounds like you might have a rod bearing going out. any gold flakes in oil?

 

I sure hope not. I don't know, I haven't changed the oil since this started. It's only been about 3500 miles since the last oil change. I'll probably do it this weekend to check.

 

Heard this once or twice too on my truck before i switched to 0w-30 mobil 1. But Never had any issues, doesnt use any oil and she just keeps on going. I vote normal, keep driving

 

Rod bearing knock almost always gets louder as the engine warms, not quieter.

However rod knock could be a possibility if there's sludge clogging up oil passages, but that's only if you haven't been changing oil/filter at specified intervals.

Edit: I still vote normal

 

I get this when it is cold outside. It sounds like it is a top-end knock. It almost sounds like it is running too lean upon startup, when it is cold. Also, I have heard that the valve timing relies on oil pressure, so maybe that has something to do with it? Some mornings it is very noticeable.

There have been some threads mentioning bad oil pumps too...

 

These were mainly early 2nd gens, right?

 

Oil has been changed every 5k miles, sometimes a few hundred miles sooner so I wouldn't suspect any sludge. The noise only lasts for maybe 15-30 seconds then goes away.

 

I actually didn't know that. Whew, I may be okay then.

 

Yep, that's exactly like mine. Oil changed religiously at 5k intervals. Noise is loudest at startup, and is pretty much gone after a minute, unless it's really cold. I've researched it many times on here and read weak oil pumps, lifter taps, etc.. Yet I've never read where someone actually diagnosed and stopped it. Just a bunch of people with similar issue and still driving. I'm at 130k-ish miles and have yet to notice any performance issues. My next oil change when I return home I might send the oil off to one of those labs just for curiosity sake and see if they detect anything foreign in there. Other than that I'll just keep letting the truck warm up for a bit and turn the volume up on the radio.

 

My 09 knocked upon startup earlier this winter when we had a cold snap and temps in the negative digits. Unfortunately it got worse, and to the point it was knocking while driving, especially upon deceleration. Here's the result.... #6 rod bearing destroyed.. Looks like premature failure, likely due to material fatigue. The journal looked fine as well as both halves of the connecting rods big end. I pulled the other 5 caps and their corresponding bearings looked perfect...... Go figure. I installed another bearing and will be putting it all back together today.

118,000 mi, oil/filter every 5000 w/Royal Purple.