2019 Tacoma 4 Cyl rattle on cold start

Temperature is 42 degrees in my area, and when i started my tacoma this morning, it did not rattle, i observed that only rattle in the temp range of 50 degrees, as it happened 3 times already and all the same temp range at 50’

 

@tacogent20
Mine doesn't do it every day, the temperature has something to do with it, however it's not the deciding factor. It's intermittent for sure.

@tojnom20
I'll check my air box as I replaced my filter a few months ago, however I highly doubt that's my issue or yours.... Maybe we'll both get lucky...

If the problem continues it'll be time to run some seafoam in the crank case for about 500 miles and change the oil

 

Hey guys, sorry, i have not contributed for a while because i been observing my truck, about the rattle. Here is the update
My battery died 2 weeks ago, and i replaced it, rattle still there, i was wondering why my battery died, so i took out my alternator and brought it to O’Reilly s and they checked it and failed, i replaced my alternator and rattle with additional check engine came out, i ran rout of option so i brought it to the dealership and 30 mins, they figured it out, fuse connecting computer to the alternator burnt, with no communication betwen ECm and alternator, telling alternator to randomly produce voltage that broke my alternator and battery, they replaced ETC number 1fuse and my alternator worked as it should be and did not hear rattle so far, it makes sense, alternator and computer is not given enough voltage to VVT actuators and it happens when temp is below 50 because battery drops when it is cold and when oil is still thicker,

i hope this helps you guys, start bychecking fuse, alternator voltage and battery voltage.

 

Very interesting.

Its been cold here and I've only heard the rattle once since changing my oil.

I'll check my fuses and relays though

 

ETC?

Do you mean this guy?

 

10 amps below towing and Abs, 2 of them. ETCs

 

The fuse is not the culprit, its the result of bad alternator regulator, the alternator gives out fluctuating voltage to vvt actuators that gives out pressure (oil) to VVTI cam, that pushes valves, if the VVTi cam doesnt receive enough oil pressure from vvta actuators because of low voltage, it rattles. The alternator is supposed to give out higher voltage at start, around 13.7 to 14.6 volts to give enough voltage to actuators and after few seconds it levels out to 13.7, but it doesn’t because the voltage regulator only gives out bare minimum which is below 13.7. Engine will still start but with slow response, poor acceleration and poor valve timing. Due to voltage fluctuations, the computer will eventually cut fuse when it receives higher voltage than required and gives out PO560, “check Charging System “ and if the voltage spike higher than normal.
Your alternator might still be giving out bare minimum voltage, bring it to Oreily’s or any parts store and they will check your alternator, mine failed also have your battery checked too, because mine broke because of the alternator.

 

Please post if you have positive information from my post. Thank you

 

Thanks for explaining.

I'm actually going to replace my battery. It's 5 years old and I feel like I'm on borrowed time with it. I haven't had the rattle in a couple weeks now. But what your saying makes sense .. my battery is due for a check and probably needs to be replaced.

 

How long has been going on? maybe drain the oil and look for metal shavings, if it is does go metal on metal or hard fraction, oil will show and check filter too

 

I just changed my oil. This issue is recent for me.

 

Just wanted to give everya heads up.

My issue started when the temps started to drop (which here in NJ wasn't until mid November). It wasn't/isn't an all-the-time issue, it is more intermittent.

Step 1 (mid November)
Check the oil.. it was low by about 1/4 quart.... Added oil and the problem was still intermittent.

Step 2 (late November)
Check under the hood for poorly fitting filter seals or anything loose that might be an issue.. I'm under the hood more than the average person so I might have forgotten to tighten something or put something back incorrectly. I didn't find any out of place.

Step 3 (early December)
Cange the oil and filter(I was due anyway). I read somewhere that the anti drainback valve can stick in OEM filter imposters. Replaced oil with the same oil I've been using for 60k and replaced filter with OEM (always). Problem was still very intermittent and by this time the temps had dropped (sometimes into the teens). I've had the cold start rattle a few times .. still intermittent, but less

Step 4 -- (mid/late December)
Change Battery with Toyota True Start 60month OEM. Although I'm still not confident this could possibly solve the problem @tacogent20 put up some valuable information and since my battery was manufactured on 1/13/20 and it's the original from the factory 60month battery and the temperature is 15 degrees in the AM I figured it's time to replace it anyway.. I don't need a situation where I get in after ice hockey practice at 10:30 and find my truck won't start... I gave my jump pack to my mom and I don't want to be stranded.

It's only been a week, but I haven't had any issues at all.

Fingers crossed here...

 

So maybe a long shot but i recently inherited a low mile 07 sienna with 50k, it has an oil cooler and vvt hose that has rubber sections that are prone to cracking and blowing out all the oil. They changed them to all metal lines 2010 ish anywho, i recently changed them for preventive maintenance well the vvt hose has a mesh screen that goes into the engine block that i pulled out and cleaned debris. It got me thinking about the 2tr and it looks like there is a screen on the side of the engine that you may want to pull out and clean and or replace.

https://www.youtube.com/watch?v=fGE-TchVFK8

 

Maybe...

My truck is still under 100k so I'm trying to avoid pulling stuff apart unless it's fairly simple. From the short video it appears I would have to remove the header in order to get to this screen.....

 

Thats intake manifold side, may be able to sneak in in without removing too much. That video shows the location of the filter/screen they could have the manifold off for another reason maybe not. Agree i would not go too deep but if its somewhat accessible worth the effort.

 

Are you still problem free? Did this solve the issue the issue permanently?

 

We've got snow and 18 degrees temps. Since replacing my battery I've heard the rattle once.

The other day I started my truck to warm it up and my radio had a message when I got in 5 minutes later saying that low oil pressure was detected and to schedule service.

I turned off the truck and restarted it. No message... I'm assuming the cold weather had my truck not wanting to act normal.

 

My low oil pressure light seems to now be a daily occurrence. The temps have been hovering between 6 and 18 degrees in the AM when I start my truck up for work.

Oddly enough the cold start rattle is still intermittent. At this point I'm changing my oil again after running some seafoam through the crankcase. I will be going to my local Toyota dealership and purchasing a few "known good" OEM filters and using them in place of the ones I bought from EBAY (they don't look like fakes, but what do I know --- who would even fake a $5 oil filter anyway).
I will also be running mobile 1 this go around in lieu of Pennzoil platinum.

We shall see if these changes yield any results. We still have plenty of cold weather to deal with and now more than ever I'm suspecting these eBay oil filters as imposters or faulty..... I had purchased a out 10 filters when my truck was new and used them all up.... I purchased another 10 from eBay and that's oddly enough when I started having these random problems...

 

I still hear intermittent rattle, but not often, and one time, low oil pressure light flashed for a second and disappeared. Im preparing for the worse, “VVTI Camshaft sprocket “ might be the culprit…

 

I went and bought 3 oil filters from my local Toyota dealership. I ran 6oz of seafoam in the crankcase for 600 miles. Drained oil, replaced Pennzoil Platinum 0w20 syn with Mobile 1 0w20 syn. Replaced eBay "OEM" filter with one of the filters I purchased from Toyota. I can't see any difference on the filter housing.

At this point I'm not sure that the filter is my problem, but time will tell. .. I saved the suspect filter to open up and compare. We still have plenty of cold weather left