Engine timing off crackling sound

Triggered.

 

To the OP: my 2000 tacoma 3.4 v6 has done this ever since I bought it in 2008 with 80k miles. It does it on rare occasions, depends on throttle position and engine load and who know’s what else. For what it’s worth, I have well over 200k miles on it now and it’s still running, never left me stranded. I got to drive my friends 2014 tacoma 4.0L and it also did it a few times. Sounds like tin foil crinkling.

 

Did you ever find a cause for this? I have the same issue, intermittently. Seems to be when the transmission fluid is between 59 and 80 degrees. The timing will drop to between 0 and -9 degrees.

 

Not to get into a pissing match but I wouldn’t call rotted frames proven reliability.

And no, the frames are different

 

My second Gen has a mint frame. Not a spot of rust on it. Oh, and it's original.

 

Haven't yet.
Not happening often enough to really piss me off yet.
Based on some reading, suspect it could be oil control valves.

edit: happens to me at a variety of temps & weather. within a few minutes of startup and after 30+ minutes on highway equally likely. Haven't found a pattern for when it happens.

 

Thanks for the replies. And just to clarify. I’m not talking about the pinging noise the fuel injectors make.
Is like the chain gurgling sound when the timing is off in older cars.
I haven’t heard that sound in one of my trucks/cars in probably 20 years. Till now :-(

 

OP,

I've got a 2016 3.5L 2wd auto truck. I bought it used with about 25K miles on it. She was filled up with 87 octane when I bought her (damn socal crap gas). I noticed on two occasions that there was detonation when starting the truck (the "crackling sound" you speak of). And like you said, it wasn't just a ping or two, sounded very bad, but only lasted a second. Couple things worth noting. After I bought her I pulled the negative terminal to reset the ECU/TCU, plus it had the 87 octane. Since I had reset the ECU, it could have been setting fuel trims at that point. These engines have knock sensors and will adjust timing/afr accordingly to prevent future knocks.

After that first tank of gas I filled with 89 octane (medium grade for us), no more detonation. Could have very well had nothing to do with the change in octane though. Now, I never had detonation during accel, only the two times after initial crank over of engine (cold mornings in socal are ~50F). Since that 89 tank I have filled with 91 (best we got), and the accel off idle feels a lot better (again, never had detonation off idle, accel just felt sluggish on 87/9 octane).

Not to scare you, but I would seriously consider taking your truck in for inspection at the dealer. Especially if you can recreate the issue under certain circumstances. Detonation is very bad for an engine, and Toyota should be held accountable if their engines knock like crazy. Just my 2 cents

Hope some of that info helps

 

Fully triggered

 

What year? Post a pic up so we can all see

 

The ecm controls the timing on our trucks, it either advances or retards it based on various conditions. If it's retarding timing, something is telling it to do so, and that something could be a knock sensor or something resonating in the exhaust. I would check and make sure the exhaust is oem & routing is original and nothing's hitting or resonating on it.
A knock sensor failure should trigger a code, but if all else is oem I'd try replacing with a known good one. We know we've had some issues with faulty cps sensors that don't leave a trail (code) too, so I'd be suspicious of that also.

Ether way it's a bummer for those with the issue and the dealer should be doing his best to help, as emission components have 80k warranty.

Let us know if anything's resolved.

 

It definitely says in the manual some knocking is normal. I tried to find it again but was unsuccessful. Mainly it said on an incline, guessing because of the loss of oil due to gravity. If you’re not getting a CEL I wouldn’t worry too much. The knock sensor should trigger if it’s an actual problem. If you’re worried take it an and see if there are any stored codes and have them check it out