You're the best, dude. Not only did you pioneer this inventive swap, you stand behind your work. Really appreciate you, can't wait to feel the car at full power.
The deductive methodology you used was probably the best possible way to diagnose this issue. Each step kind of was necessary in order to rule out everything else.
I strongly agree. I realize it's easy to say this with hindsight AND from the peanut gallery but with those injector test results I'd immediately be wondering "Did I burn up valves?" , "Is there scoring in that cylinder now?" etc.; I wouldn't be able to sleep without confirming the rest. Sucks doing an engine pull to just to find out the real problem but at least it removes uncertainty down the road.
Running that lean would've been catastrophic and yet he pushed it round the track until it finishes, it's a miracle that cylinder survives. Great to see comprehensive diagnostic Marc, thx for the vid.
Unfortunately there was no sign of running lean, i was even there at the mid-ohio loss to look at logs and try to figure out what was going on and even I told him that despite being down on power everything was running right so to keep taking it out there. From what i understand the injector was going from running to fully shutting off quick enough that the engine never spent much time in the running lean region of operation so nothing burned up.
@nsteinMotorworks So it's the works of a faulty injector that made those behavior then? In your vid it seems that the 4th injector are almost fully absent on high frequency (rpms), I think it might've behaved differently like you said it being shutting off briefly when they're connected to the ECU, since all the sensors can detect abnormality from the engine.
@@FrankensteinMotorworkscould it have also been a situation where the other 3 cylinders were running rich, offsetting the lean condition of the #4 (as far as the readings on the WBO2 is concerned)? Was duty cycle checked in the logs to see if the duty cycle of the injectors was abnormally high?
@@kenny240Yes, the abnormal fuel use did show in the logs but we were seeing airflow inconsistencies also so there was a bunch of stuff that together did not align to a diagnosis. In hind sight it's very obvious with the information i had but i did not put it together at the time.
@@FrankensteinMotorworks I wouldn’t mind that 😉 I have a 2018 WRX as of now. I just ported and polished the factory turbo and installed billet turbo wheels. Currently making around 340whp, but it’s nowhere near as reliable as my Scion was. The car had almost 200K on it and needed some work done to it, mainly just suspension components and drivetrain mounts due to them being old and almost all original. My ideal build was forged internals, with your cams and valve springs, and a turbo. I just couldn’t justify spending that much money on all of those performance mods and ignoring what actually needed to be fixed on it. My Fiancée owns a 2016 tC with a 6-Speed, so I still get my fix tC when I’m driving her car. Love the fact she wanted it to be a 6-Speed since she learned how to drive manual in my car.
Love seeing someone put the hand up and stand behind their work, and also admit when they're stumped with something Funnily enough, the best way to show competence and knowledge is by admitting you don't know something. Straight away you can trust the guy that knows enough to say he doesn't know
Ouch! Rich is a bummer but lean is a killer, good that you figured it out! I had a I4 Camry and an injector died, at very high RPM is felt almost normal.
Way to go Marc! I met you and the Ben's at Mid-Ohio and we actually discussed the lack of power that day on the tracks dyno..... Full circle and here we are with an answer to the riddle. You are a wizard and this video put a huge smile on my face knowing this weight is off your shoulders now. Hope to see you all again at Mid-Ohio this coming season 🤘🤘
Nice detective work, and thanks for sharing the whole process so openly. Really interesting to see your process. Have you guys considered throwing some ID injectors in that bad boy? They do an amazing job of balancing and characterizing their injectors.
Injector dynamics really does make some nice injectors and what they do is crucial when you larger flow injectors but the goal of showing off this build was to show off what could be done with low budget using only factory parts. Keep in mind this motor is build using OEM toyota hybrid 2AR-FXE camshafts. I have other builds on my channel making much better power that do use Bosch 980cc injectors but when i grow beyond those i will likely be contacting injector dynamics for bigger ones.
I cant explain exactly why but your videos have this style to them that makes it seem like a really amazing lecture AND entertaining. Like I feel like I am more calm and more intelligent and more relaxed after watching this
Most of the population is asleep now while I'm leaned in and locked onto every piece of information. Lol. I hate that you had to do a full tear down but sometimes it's gotta be that way. Fascinating . Thank you
Holy cow what a weird failure! No surprise that so many people looked at it and couldn't find the issue. I have a couple weird ones like this every year. Always a pull your hair out scenario until you finally find the source. Congratulations on persevering and finding the root cause! 👏
I really debated if i should post this at all, i expected the internet to call me an idiot for not noticing this earlier but the responses have been surprisingly positive. But no matter what i try to be as honest as possible with my results on these engines so even failures have to be shown and everyone can learn something.
You posted a new video so soon after my "where'dyougo" comment on your previous video hah. :D Welcome back, it was a great episode with great content of a nice car. (I watched the video within 5 minutes of you publishing it but forgot to comment until now)
Marc, I think developing the 1ar has more potential due to more displacement and could potentially beat the k24. As of now, this scion motor doesn’t even have variable valve timing, just a k24 minus vtec.
That's such a wild finding, sucks that you had to tear down the engine before you found it. Love seeing this saga come to an end, now it's just up to how well Ben can handle his schizophrenic chassis on the track! Looking forward to this season for sure @GearsandGasoline!
Awesome sleuthing boss! Now you know that this is a thing, so a full tear down should not be needed.. Live, learn and document.. Can’t wait to see Lin get on track again
I'm not sure if the Haltech that you guys are using has the capability, but it probably wouldn't be a bad idea to start using EGT sensors on all the build proceeding this one. It really helps with diagnosing this type of problem.
Yeah, i am very happy that the motor was actually still in great shape. That part honestly really surprised me. I would have expected a melted down cylinder with this kind of failure.
Cars are simultaneously the best and worst thing ever. I’ve never had something make me feel as angry and also happy as fixing what i thought was a complicated issue on my car that turned out to be a simple fix.
Yeah, i can't wait to see how he does with the car now that it has the power it was supposed to have in the first place. It's still at a bit of a disadvantage for the GLTC class but 15% more power should still make a big difference.
I have been watching/following you for two years now and love seeing the progression on the 2AR-FE and its variants. As an Engineer myself, I love your though process and execution as it was well planned out. I currently own a M/T 2014 scion tC for 4 years now and I was thinking of AWD converting the car. I have been looking at the rav4 AWD as a donor parts as the architecture is similar. The problem I would see is the parasitic loses in the drive train, but looking at your simple modification to increase the HP really could make this project work. I love to see what future innovations we will see this year for the engine.
Usually the biggest issue with an AWD conversion is getting a big enough trans tunnel and still having space for the fuel tank. the 2014 tC also has the EB60 transmission and that has no center differential option so if you go AWD you'll need an electronically controlled clutched rear differential or switch the transmission for the previous version that does have a center differential option available.
@@FrankensteinMotorworks BUT, you have a new thing to look for when doing a preliminary evaluation moving forward. so it wasn't really time wasted as it can save you from repeating this in the future.
Steps for checking injectors. Remove engine and disassemble head......... Double edge sword with this one. It was only the injector. But you had to take the engine apart. But luckily it wasn't something catastrophic.
Yeah, i took the really really long way around on this one. But to be fair many other professionals had taken a look at the car and not figured it out either so i don't feel that bad. Just slightly annoyed i had to do that much labor to figure it out.
I’ve got an AW11 MR2 sitting in my yard with its stock 4AGE on a stand. Knowing that engine is the same price and makes double the power has me in a real pickle.
Holy crap Marc! I just got off the dyno with a 2gr that was behaving eerily similar to this unexplained fuel trim asychrony (> 10%), missing power but not a whole cylinder work. I had been searching for a spark problem, but none exists.
These failures are the ones that really rip your hair out and take years off your lives. Glad you stayed in it and figured out the problem, bet that felt like you discovered Atlantis lol
Been following this, thank you for the complete explanation. In the very early beginning of understanding EFI and standalone tuning, i went through two different sets of injectors that one of the 4 went bad. Not easy to pinpoint without experience and the right tools. Individual egt sensors would be nice but not all can afford to.
Yeah, dropping a motor twice, once to carefully check that the motor is still in time and another for a full disassembly just to find a bad injector certainly was a bit more than i was hoping for.
Last few years Its become a regimen for anything I am working on to have the injectors checked and cleaned. Recenty had a rb26 come in for some service work with some mild driveability issues. Turns out 2 injectors were not as strong as the rest.
I've had other issues with injectors, that's why i bought that machine to begin with. This did not give me those indications but you're absolutely right, i think injectors will start getting tested just as a matter of course these days.
Something similar happened to me. I developed a sudden idle issue and notice my oil (on the dipstick) was milky. I disassembled the motor (not the short block) and discovered the head gasket was fine. I spotted a horizontal line of oil residue on the turbo cold side after disassembly. The side of the turbo that faced the valve cover. It never occurred to me the idle issue was that the seal for the valve cover was blowing air and oil. Air was getting in past the VC seal. In part because I had switched to a 2 into 1 catch can system (crank case vent and VC vent), and it was overwhelming it. So, had I kept my old 2 catch can system that worked, I wouldn’t have had higher pressures in the head…and I wound’t have had the valve cover gasket failure, which caused the idle issue. 🤦♂️ Cost me labor, a new head gasket, new VC gasket and other ancillaries. 8/10 times, the issue is simpler than we think.
Glad to see you back, Marc. Hindsight is always 20/20, and the tune wasn’t the only problem. Simply amazed that the engine didn’t burn up on cylinder number 4 running that lean (saved by running e85?). I am still baffled why this wouldn’t show up on fuel trims, as the ECU would add STFT to compensate for the lean condition on #4…which would also reduce power on the remaining cylinders as a result of being rich. The reversion to the “base” tune, which pulled ignition timing, may have what saved the engine during Ben’s race. E85 (which lowers combustion temperatures and tolerates more ignition timing) and the less advanced ignition timing from the wrong base tune likely prevented a catastrophic failure.
It did actually show up on fuel trims. We figured that out a while back but we could never figure out what that positive fuel trim meant. in hind sight we certainly should have dug further into those positive fuel trims. I think the biggest thing that saved the engine was that the cylinder almost entirely shut down, it was probably well below the low flamability limits at higher RPM. But that's not the entire picture since we do have evidence on the valve that it was running hot when it was running.
@@FrankensteinMotorworks it likely shut down at wide open throttle and close to redline, but if it was idling acceptably and dropping flow at higher injector duration, it had to run lean in between idle and full throttle. The good news is that no damage was done. I don’t think it would have worked out that way on gasoline, though I am speculating.
@@FrankensteinMotorworks with the retarded ignition timing though, yes? You are likely right…under high load conditions, it likely was too lean in cylinder #4 to he combusting at all.
Now THAT is digging in and finding the issue. Killer stuff, man. Question: would a 2AR swap make sense in an AW11 MR2? A 220ish hp NA engine in that car would make for an awesome daily/back road burner...