2GR-FKS failure at 150K, looking for input/some questions

I ain't sensitive, no worries. I had no idea RON was a thing, do you know what the difference is? I'm gonna try finding the manual, I swear the heavy use interval was 3,500 miles and the service dept was good for it, only problem is the cab is basically a parts dept at the moment.

 

I mean, technically yeah but it's more of an engine bay dressing. Initially all the intake components had reflection tape over a double layer of mylar wrap with a forcing cone replacing the flat hole in the fender to try and get the air as cool as possible while using the truck for work. That's what the vents are for as well. It ended up being mostly to get the bay looking as clean as possible.

At idle, air temps dropped about 10 deg but on the highway it was closer to 45-50 deg which I was happy with. Plus on cold mornings if I rolled down the windows you could feel the hot air from the engine bay pass by the mirrors which was pretty cool. Having a vented hood helped with the mpg on the highway too by pushing some of the air out from that big ass grill.

I'm set for an appointment two weeks from today with a shop to do a teardown of the motor to see if its salvageable. Original quote is $5000 out the door to maganflux, hot tank, polish crank, replace pistons, hone cylinders, deck block and head and swap out valves/timing components. I'll keep shopping around in the meantime but the next big update will probably be a month from then as the shop quotes about one month for the work to be done.

 

People wreck them every day, especially this time of year. Hope an excellent used one shows up to save some $$.

 

Manual is online, that's where I found it. RON is what I believe other regions use and the fuel is measured differently than ours, or something like that. I'm sure a fuel nerd could answer it better, but otherwise ask Jeeves because I don't know exactly.

 

Sacramento, 50K engine…

https://sacramento.craigslist.org/pts/d/rio-linda-tacoma-parts/7427735274.html

 

no odometer picture.... you would think that would be a requirement when selling an engine

 

I'll sell you the engine from my 2019, around 4K miles on it (I'll have to check).

 

No more super charger?

 

Still have the charger, but if the offer for the stock engine is good, I'll build another from the ground up.... or 2UR-GSE 5.0L swap.

 

Hey Hey, this thread got away from me but I'm back with the updates after the break-in period. The truck runs again and is as sick as ever. So what happened?

Connecting rod in cylinder no 5 failed and sent the piston to the head contacting the valves and causing light damage to the head itself. Very light scoring in the cylinder and damage to the crankshaft as well. The connecting rod was shattered in multiple pieces with obvious heat damage. Luckily, the crankshaft was able to be reground, and the head was salvageable. We couldn't find anything particularly wrong that would look like a reason for the connecting rod to have failed the way it did besides the heat scoring, pan still had clean oil.

My initial plan was to replace all the rods and the crank with MWR sets to set the truck up for boost down the line, but with the supply chain price gouging and lead times, that wasn't gonna end up happening. We inspected the 5 other rods and all looked well, replaced number 5 with OEM parts and rebalanced the crankshaft. Very light honing of the cylinders and ring replacements as well.

Valves and guides were replaced, seals obviously, and all new timing components.

700 mile and 1K mile break-in period with another 500 babying the truck to be safe and I'm back to a place of confidence with the motor.

All said and done, rebuild took 4 months and cost 8 grand total out the door, high price and long wait due mostly to OEM components being on backorder from Toyota.

 

Although the engine runs well, its obvious it needs injectors serviced which sucks because its damn close to 2 grand for just the injectors. I'm happy overall to have the thing running well again, but it does suck that my plans for the thing have been derailed due to the rebuild. That being said, I have several things laying around that will be going up for sale to try and get the funds back up for the long travel project.

...and now to read through the replies....

 

why do you think the injectors need servicing if it runs well?

 

Cylinder #5 seems to pop up a lot...
Did they give a reason why it's connecting rod failed?

 

On initial startup, for about 5 seconds she shutters like bad gas. No coolant loss, no vacuum leaks, no dirty oil, spark is good. After those few seconds idle is good and stays good until warm and runs from then on with no issues. That initial hesitation with no other symptoms tells me injectors might not be giving consistent flow on startup, which would make sense for a truck that's been sitting for months on end with everything else being basically new.

 

Couldn't find anything particularly wrong besides some heat scoring on the top end of the rod. My builder said he's seen cylinder overheats a bunch in the 4.0, but I was the first 3.5 he's seen with similar failure. I was nervous about the rebuild without finding a cause for the failure in the first place but he said he hadn't had any issues with his 4.0 rebuilds. The go to is to polish out the fluid passages to make sure everything is properly cooled and make sure fitment everywhere is good.

I did do a lot of reading on the 2GR platform from some track guys since they seem to be the ones with the most experience and cylinder 5 failure seems to come up a lot from improper lubrication and overheating, usually from oil pressure being insufficient at times as the engine experiences forces during a hard turn. I guess it could be possible to have a similar failure result from the truck being on a partial incline causing the oil to slosh to one side away from the oil pickup tube and decreasing pressure which would be felt worse in cylinders 5 and 6 since they're the farthest away, but that's obviously all guess work.

I might try boosting cooling capacity for my own peace of mind, bigger radiator and at least an oil pressure gauge. we'll see

 

If you haven't already, fill er up with super unleaded and see if that helps.

Not the engine (frame) but mine sat for 3 months at Toyota with almost a full tank of regular. I don't recall it running rough like yours but it might have, I just did it more as cheap insurance.

 

Hydrolock from leaking injector???

 

At $8k and 4 months to rebuild why didn't you go with a low mile wreck motor for $3k as stated in the OP? Just curious on your reasonings.

 

That, and why not sell it now and get away from it? If it's not running 100% after rebuild, time to part ways. JMO.

 

It was a combination of a few things. I didn't like the idea of swapping in a used motor having no idea how it was maintained, the cheapest used motor I could find that I was comfortable with was $4K, and I found a builder that offered me a 6 year warranty with unlimited miles that came well recommended.