2010 PRIUS IV - engine/transmission - headache/migraine

To preface, I've been trying to read here as much as possible, and check youtube, etc prior to actually "wasting" a post here! I didn't really want to make my own thread but I'm pretty much at a wall right now!

So, I have my 2010 Prius IV (four) that I do use for personal and full time ride-share driving work. It currently has between 290,000 and 291,000 miles. Not that long ago it started, what seems to be a notorious, engine shaking/shuddering/clattering that absolutely freaked me out! When it very first started the symptom only seemed to present itself at around 55 MPH, while on the highway. CEL did come on and it was throwing DTC's for random misfires, and misfires in CYL 2 and 4. I honestly didn't recall the mileage the vehicle had when I bought it (had to be somewhere in the 200's already though) so I figured I should probably do the plugs/coils anyway @ the 290k that I am at. So after I did the plugs (ALL personally gapped and put in to exactly 15 FT LBs) and coils it did start to run better, but it was still acting funny. After doing more research I saw all the "stuff" about head gasket failure, EGR clogs/failures, the intake manifold TSB, and so on. Well, being winter here in Chicago and not having a garage of my own I couldn't personally dig into this level of DIY right now, I had borrowed a friends garage for the plugs/coils knowing that was going to be a quick job! So, I bring the car to a 'general shop' where my old neighbor works. They're not a full service shop, but long story short NOBODY there can figure it out! No problem, so I ask them where they would go in terms of a "full service" shop. They give me a reference and so I plan to bring the car there. I ran a tank of 93 octane fuel and seafoam to try to make sure the injectors are "clean" too BTW. Take it to the "full service shop" after that tank of gas because nothing was getting better. They notice the car is NOT throwing any more DTC's since resetting them after doing the plugs/coils. I *insist* they perform a leakdown and/or a compression test and otherwise verify the integrity of the H/G, after seeing all the H/G issues these cars and the "clatter" have! He said they did indeed check the integrity of the H/G, and that it was good for sure. He referenced the TSB for the manifold, so I authorized him to replace the intake manifold, replace the PCV (which I wanted to do when I did the plugs but just couldn't), CLEAN the EGR *system* (tube, valve, and cooler). After they completed these repairs for me, he said the engine is definitely running "sound" now, and as far as he can tell, doesn't require ANY further attention at this time. Certainly was still not throwing any CEL / DTC's! He did add that the car does still have a "problem" he noticed while test driving, and he thought it was related to the fact that the condition of the transmission input shaft damper assembly looked to be rather poor (especially the springs, they "look all rusty"). He also mentioned he believed he thought he saw a "hairline" CRACK possibly starting ON the flywheel. So I pay for services already rendered and drive the car around all day to "test" it "nice and good". The problem for quite a while was *exactly* as he described. There is still a weird clattering, but didn't seem to really be any actual shaking/vibration with it anymore. It only occurred when accelerating "smooth" (like you would when you're driving for hire!), and if you accelerated "hard" (I guess like you would in a "normal car", if you weren't actually driving a Prius how they were MEANT to be driven), it does seem to not happen, or even make it STOP happening if it's already happening. Still kinda freaky, but I actually began to wonder if I couldn't just get back to work before having to continue down the diagnosing/fixing path! But I keep driving around, because when I am driving around for hire/work - I do tend to do in upwards of 300 miles per day! Eventually it did/does seem to gradually get worse the longer it's driven. The problem from the very beginning has been that way. Minimal or completely non existent when cold at the beginning of the day. As more time goes by, and the vehicle components get warm/hot - it gets worse! So I keep driving it around! Eventually I finally get to the situation where it kicks the ICE on at a stop light to either charge the EV battery or maintain temperature for cabin heat. Dang it! The vibration was back. The SOUND and VIBRATION it made, even while sitting at a stop in Drive, was SO bad (to me). While in the state of the ICE being on for EV/TEMP, acceleration of ANY kind (smooth or hard or SUPER hard) just seemed to make things worse! The sound and vibration became rather heavily amplified now/then! Now I know for sure, I should NOT return to work before further diagnosing and fixing whatever the heck is wrong with my babay, or (shh) replacing her!

So I called the shop this morning where I just had the intake/pcv/egr work done to clarify: the transmission input shaft damper assembly looked bad and that there was a possible "hairline crack" starting in the flywheel. I told him about how for the most part things were as he described, and I was actually pretty close to just going back to work (gotta make $$$ to fix stuff!) because I honestly thought it WAS going to be "tolerable" to any potential customers I'd have in the car. Even like my GF pointed out, *I* am noticing it because I KNOW it's there, she said it was really so unnoticeable after getting it back from the shop - that no customer would realize there may be a "problem" - that if they did even notice it they'd likely dismiss it as "normal road noise/vibration"! UNTIL the ICE kicked in at a red light to charge the EV battery and/or maintain temps for cabin heat! That's when I knew for sure, there's NO way I'm risking something like that happening with a customer in the car! So the guy at the shop re-iterated that there's NOTHING else wrong with the engine/motor (ICE), it's running "prime". He said that he (his shop) COULD do the flywheel and or the transmission input shaft damper assembly, but if the problem is any further in the transmission, he does not do transmission work there and would have to refer me to a transmission place! He did add that he actually already "marked" the spot on the flywheel that he was talking about in the event I took it anywhere else to have it worked on, so that it would stick out to them so that they knew it was there too! He also offered to throw the car on a lift Monday for me and actually show me everything he's talking about. So far the both of us have agreed that I will drive the car around until it's nice and hot Monday, and then pick him up so I can demonstrate/replicate the issue "at it's worst" for him (with him in the car)! Then we will return to the shop where he will put the car on a lift and show me everything he was talking about with the flywheel&damper assembly.

Now, I am absolutely torn! I have not worked in almost a month now, between being sick and these car "issues"! So I just want to get back to work ASAP, but cannot until this vehicle is either fixed or replaced! But I'm also at a point where I just really do not know what to do, because: I cannot really DIY, even if the weather was good I certainly think this is getting WAY out of my personal scope/capability! I'm already in above my head! I also don't want to keep "throwing parts at it"! Sure, it may have technically needed all the things I've already done, but I also don't want to just "throw" stuff at it HOPING it will fix this main issue, just to find out it didn't. So, should I let this guy do the flywheel and damper assembly, should I bring it straight to a transmission shop? Should I believe him that the ICE is "sound" and doesn't need any further work? Should I believe the integrity of the head gasket IS good? Should I believe it's now going to be more towards if not IN the transmission?

Well, thinking about it logically, I do actually think he is likely NOT lying about checking the H/G. At least, it doesn't appear to be losing any coolant. I will continue to monitor that though for sure! But please, seriously, please: I would LOVE some input from this Prius community! ANYTHING you have to offer would be appreciated more than you know right now!

 

That was a good read, I do think I will forward that to this new shop of mine (the one that I had do the intake/pcv/egr job). It also does re-instill the concept to me that it could be something so stupid and simple, even though it's something already done too. For example, who says all the plugs I just put in are actually good? It is almost assumed since they JUST came out of a box from a store, but factories (accidentally) allow faulty product onto store shelves all the time. That's actually more prevalent today than "yesterday"! Overall manufacturing Including QC just downright sucks... I would think this shop would've caught something like that though, but I did tell him that I just did the plugs, so maybe it got "put off" there too, just like it has been in my own mind.

However, I would also think that, if it was something like the plugs (or something else "simple" like this) that it would be more of an "always on" problem. My problem isn't really an Always On problem. I don't know that I would consider it truly "intermittent" either, but it's definitely one of the oddest problems I've ever seen in my 38 years of life! All I know is the intermittent or semi-intermittent nature of it is surely not making it any easier to diagnose/fix!

I guess in a worst case scenario I'm going to get R**** by the shop(s) that I'm going to continue taking it to until it's fixed! I really do NOT wish to replace her, the more I think about it. I really think I got lucky with the specific car that I found and now have. MOST of the Prii I looked at were the most simple/basic/crap (hate to say that but it's true). Nothing that personally appealed to me anyway, all cloth, with the most basic head unit (stereo), etc... Then one day I got *lucky* and I found my new to me Prius. It had heated leather seats, with the upgraded JBL H/U with backup cam and navigation. SOLD! Still to this day, it appears such a "luxurious" Prius is hard to come by, at least in the Chicago area market(s). I don't want to wind up "downgrading" to some lower trim package prii. I think I'm so spoiled by this first Prius IV of mine that I couldn't have anything less at this point! And I am already thinking about the "one day" factor that I will almost inevitably upgrade to a 4G Prius, but I'm still not quite ready to part with the one I have. She has at LEAST FIVE (5) more years as a work horse at that!

 

I would but, it would then be my luck that the problem *is* in the trans! =\

 

I know it may still be a very real possibility to have to wind up replacing the whole car but, at this point I pretty much think I'm already kinda too deep in to just give up now. I'm about $1200 in between the plugs and coils I did (no labor), and then the parts and labor I paid the shop to do the intake, PCV, and EGR (cleaning).

To clarify, the potential "crack" he spoke of wasn't in the shaft, it was in the flywheel. I also think that may be from over-usage while it had a misfire. Since I drove it so much for troubleshooting I do figure that could be, at least partially, responsible for the increased damage to the flywheel and the damper assembly.

Sadly, I do know that even if the ONLY remaining problems are the flywheel and the damper assembly, that itself is going to be fairly expensive. I'm guessing somewhere in the ballpark of another $2000. From what I see the damper assembly "books" for $900, but it appears to be available as low as $400/$500/$600. It also appears that the flywheel can be had for around $300. So we'll call those two parts $900-$1000. Then I'm sure there's going to be at LEAST $1000 in labor since you have to split the motor and tranny just like you were doing a clutch or torque converter...

My only 'thing' is, what if it IS more than that. Then I'd be about $3200 in, and STILL have an unknown problem to STILL fix...!

That is the exact reason I'd rather be able to find out for sure what's wrong rather than throwing parts at it. I guess as long as I keep the FINAL bill at or under an estimated $6,000, because once we reach THAT kind of price range, yes, I could have just bought another used '10 (or even newer) for that kind of money. But then again, buying another "new to me" 2010 could be just buying a whole new set of problems! Which is also why I'm still of the mindset to just fix the one I already have! That to me just may be too much of a gamble. I could get lucky and get a car that doesn't need anything and is "better". Or I could wind up with a total "Pile" that is going to wind up having MORE problems than this one!

Too much to think about, massive overload, which is why I've come here for help!

 

Yea sorry about that, I just tried to make sure to provide as MUCH information as possible about the situation. While it initially seemed really unique to me, I figure *somebody* out there had to have experienced something like it, maybe...

 

I do appreciate the input! Even if it's not "what I 'want' to hear"!

I still can't help but think at this point I will do (have done) the flywheel and damper assly. And if it does wind up being more, then sell as is to recoup as much as I can out of it then buy another Prius... Maybe I could get/be lucky and have the only remaining issue(s) being the flywheel and damper assly...?

I would hate to give up on it now, spend 6+ thousand dollars on a replacement Prius, when (just maybe) this one could have been 'finished' being fixed for only another 2k. $2,000 < $6,000(+)... Even if you count the other money already in the repairs - still - $3,200 < $6,000

=\

 

I guess it's NO help that I see articles like this all the time, and hope I can pull so much more out of mine. Especially since it's not even at 300k yet. My GF just bought a very high mileage unit that seems to be going decently strong too (has had cold start knock at least once this winter though, but only once or twice)... Hers has almost 350k! According to stories like this, mine hasn't even reached 50% of it's life LOL

 

So I took it back to the shop today so the guy could throw the car on a lift for me. Sure enough there's definitely a crack in the flywheel (what little bit you can see of it through the little viewing "window"/area without separating the engine and trans. I will provide the picture I took in this post.

This morning it did have vibration/noise on cold start, which I was able to hop out and get a little video of before driving into the shop. I will try to include that short video clip in this post if possible too.

They do seem to think the remaining noise/vibration issue is just the flywheel and the damper assembly. We did a one over on the rest of the car *together* and as they pointed out, a lot of the rest of the car looks really solid. NO leaks from the engine anywhere (main seals etc). Upon further inspection it also looks like the head gasket may have already been done (obviously before I bought it if this is the case). The "evidence" was all the orange we saw from the bottom looking up around the head and the timing chain cover. And like he said, he "guaranteed" it was not the H/G because he did a leakdown and/or a compression test when I had it in for the intake/pcv/egr. He said it actually looked really good overall for a car that had 290k on it. I would have to agree, seeing as it was the first time I saw the car from the bottom (oh how I wish I had a lift at home)! Even the mechanic/tech that actually performed the work on the car came over and said that it looked pretty well maintained for a car with 290k on it... He said the car/transmission shifted just fine when he drove it...

I still fear there may be more to all of this crappy noise/vibration issue, but I also think at this point I'm just going to have them do the flywheel and the damper assembly. He did say if I chose to do so, he would knock money off the labor seeing as I just had some other work done there. He even told me he will let me know what he can get the parts for, but to feel free to source my own parts if I can get them cheaper! He seems to completely understand that I'm already about $1200 in between the plugs/coils, intake, PCV, and EGR, and wants to try to "help" me (financially) wherever he can... I'm not sure what he/they would normally charge for such an operation in labor, but he did "estimate" the labor portion of the bill for that job would be lowered to $900 for me. That would be $100 under what I expected (as noted back in my post #8. So either he's only giving me $100 off, or maybe they'd charge more like (up to) $1200 for a job like that (to give me $300 "off")... Either way, I do appreciate any willingness to "work with me"! Should I maybe offer $800 for the labor? I know it's some 'serious' labor, I've done torque converters and clutches before (RWD cars), just not on a prius... And something like 20+ years ago LOL Would an offer for $800 for the labor be too much of a "low ball"?

Could this weird vibration/noise really be just the flywheel and damper assembly? I know all the other posts/videos I've seen around the internet always point to head gasket, and other misfire related items (plugs/coils, intake, PCV, EGR, etc), but we've already been through the motor.

I'm going to go attempt to source the parts now and see just how cheap I can find OEM parts. I'll leave the post with that pic of the flywheel/crack I took this morning... and if I can the videos of this mornings cold start up...

...And bear in mind it doesn't just do that upon startup, it will do it while driving too. Even though the idle 'smoothed out' in the video, once I jumped in the car and started driving it, the noise/vibration was present when accelerating slowly/smoothly (after the ICE kicks on). It can be reduced or (maybe) eliminated by either harder acceleration or deceleration. There is also NO noise or vibration present when the vehicle is operating on JUST the EV. It's ONLY when the ICE kicks on. It can also be semi intermittent. It doesn't literally always happen, and sometimes it's "better" and sometimes it's "worse". It definitely seems to be the worst when at a red light and the car kicks the ICE on to either charge the EV or maintain temps for cabin heat, and the acceleration while it's already running the ICE (instead of starting out on EV only) to charge/heat - is just horrible (to me)... It also doesn't appear to do it in Neutral, when I was leaving the shop it was running the ICE to charge the EV and it was doing it, so I put the gear selector into N, it stopped. Reverse or Drive, and it comes back. Back into N, went away again. It definitely seems to be either non-existent or minimal if the EV battery has sufficient charge to start from a dead stop, and get it up to some speed before 'making' the ICE kick on.

 

Yea, I'm almost sure being a transverse mounted FWD engine - either the engine or transmission will have to come (all the way) out to do that job! Which is why I was thinking way back in post#8 that this would be about 1k in labor easily. Makes me appreciate all the clutch and torque converters I have done on Mustangs and Camaros back in the day, that much more!

And that's my only fear, is that even after agreeing to do the flywheel and damper assembly that "we're" going to find a cracked input shaft, or even worse, get it back together to find out there is still Something wrong

I don't want to play this probability game on my own LOL Want to get as many opinions as I can. Even my woman seems to think there's a good chance it will wind up being just the flywheel and damper because once she saw and was able to better understand everything she made an analogy about an out of balance fan. She said what the car was doing sounded exactly like that to her. And she's right about that, eventually, at the right speed(s) and conditions and out of balance fan will 'catch itself' and smooth out. Also, adding or decreasing the rotational speed could reduce or eliminate that kind of out of balance / looseness (noise/vibration) for a period of time.

Then we found this video too! This was a pretty good video on the matter:

 

And yes, we are pretty much just "assuming" the damper is bad, just based on how rusty the flywheel is, not to mention the crack in it. The crack itself may be insignificant but if I'm sending them in there to do work, I'm surely going to replace it now while I'm sending them in there to do the damper! I do hope it will not reveal that it needs an input shaft too, but if I DO proceed with the flywheel and damper repair - I'd be WAY too far in not to just do that too! I just don't want it to be even more than those 2 or 3 things!

If it does need an input shaft, I don't believe this place does internal trans work either, so I'd have to ship (bring) the tranny to a trans shop to have the input shaft done! So no clue how much *that* will run me IF it is indeed cracked or otherwise damaged.

Sadly, there's no REAL way to know for sure if the damper assembly OR the input shaft is in *need* of replacement without breaking apart the motor and trans. At least as far as I know. So, the point we are at is "assuming" the damper is bad based upon what little visual we DO have of the flywheel (and the operational conditions of the car). So the first and main point of "sending them in" would be to replace the damper (*assuming* it's bad). Secondly may as well replace the flywheel while we're in there because it looks like crap (rusty and crack started - plus it could be worse than the little we can actually see). If it is discovered that the input shaft is bad once they go in, well, I guess I've already jumped off the diving board so I'm gonna get WET!

We do know, there's NO CEL - there are NO DTC codes being thrown! They even opined that this is one of the last few remaining things that could be wrong with the car that would not throw a code. They mentioned how almost anything else with the engine or transmission should be throwing a CEL/DTC! I'm apt to believe this...

So main questions right now are:

-Should I jump off the diving board (send them in there to do the flywheel and damper)?
-What's your opinion on estimated percentage chance it's *just* the damper/flywheel causing this issue?
-What's the opined estimated percentage chance the input shaft is cracked or otherwise damaged?
-Is there any opinions on *other/more* things it could be (beyond damper/flywheel/input shaft)?