Awful rattling when starting.

New, new engine?

 

Maybe torque plate springs. Engine bad? Fire getting put out on initial startup.

 

Did you install?

 

New oem plugs from a dealer?
Any trouble lights?

 

Yeah that definitely sucks I had a JDM spec engine and initially engine installed with a another transmission from the engine supplier I figured I'd get a transmission with similar mileage to the engine I was installing bad idea apparently everything ran good for about 3 months and then all of a sudden I have the noise you have It is not the engine missing or the fire getting put out either It is something right there between the engine and the transmission or at the transmission end of the deal when it's rattling you can put your hand on the engine in the engine is running smooth as glass apparently something else that's reciprocating is not happy and I don't think it's in the engine it's over in the drive line or something which would be part of the transmission the wheels are not turning at this point we're just sitting in the driveway in drive foot on the parking brake shift into neutral the noise will go away but if I flutter the gas a little bit while in neutral I can make it make the rattle when it's not rattling the engine is still running smooth as glass not skipping a beat If it was like an old car with spark plug wires I could lift the wires off each plug and make it skip perfectly not going to do that in a Prius easily.

 

I have my original transmission and torque plate sitting here ready to go back in this will be the last thing I do to this car If this doesn't straighten it out this is the last generation 3 I have and it will go to the trash We are not having anymore of this this is just a very sick joke of the situation and I will not partake anymore going forward I don't see myself buying anything from 2010 to 2024 so far the Prius is out of my eyesight generation 2s aren't but all this other nonsense not going to happen this is like the Nissan stanza of Toyota. If you don't remember that joke of a car well you're lucky.

 

Would timing chain off a tooth even run? If so, might be that?

 

Everything in the transmission that is spinning in P is still spinning in N; there isn't anything that disengages. But N cuts off the electrical power generation, so the engine is under less load. It's a "real" idle in N, and can be more "doing work at idle speed" in P when the battery is to be charged.

So the engine is running roughly under load, smoothly under no load. In a Prius, a rough-running engine (for any reason) will make that awful clatter with the transmission, because the transmission also has massive rotating elements that are not going to match the irregular engine rotation. (The input damper is there to try to gloss over that, but it can only do so much, and can eventually be worn out by doing it.)

"Engine misfires under load" is a diagnostic situation with sort of a list of Usual Suspects.

 

So again it looks like we are sticking to the guns that anytime the engine or anytime the system makes this rattling noise the fire's getting put out in the cylinder I got no problems with that only issue is right now that even under load where the clanking is going on the engine is running smooth as glass You can see this in a few videos that I've made which are kind of pointless because they don't really show anything other than the engines running smooth as glass I can rest my hand on it I can play a mattress on top of that engine and sleep on it with it running and I have to flutter the gas and fiddle fart around with the car sitting like in my driveway The minute I put it in drive and start to try to drive then the clanking is on as soon as it gets up past the center line in the generation 3 of the consumption or energy monitor where it turns red the rattling more or less goes away then if I back my foot off the gas and let the red clear to be in the good gas mileage range the rattle comes back pulling into the driveway the rattle will almost shut right off like a switch is turned it off but the engine still running smooth as glass I swear to God it seems to be right there where the transmission front of the transmission and the very back of the torque plate If I listen with my stethoscope that's what I hear and I understand I hear that because we believe the engine is missing under this load and it's causing this rival I do understand that only problem is right now I don't see any cooling in the cylinders Don't smell any coolant coming out of the spark plug holes . The engine is the one we bought JDM and put in along with a transmission from the same people The only recourse I have at this point is to take the car back over to my buddy's place pull the transmission out and see if the torque plate that came with the engine that got used my initial thought was it would have less mileage and being better shape just the metal and the springs themselves apparently not. And this car worked with this newer transmission in engine for about 90 days flawlessly quiet no problem never low on oil never low on coolant nothing pretty boring actually and then all of a sudden we noticed the rattle sitting in the driveway I think initially.

 

The clanking you hear is the sound of the rotating engine flywheel not matching the rotation of the massive bits inside the transmission. The speed of the engine crankshaft isn't constant through a whole two revolutions, it speeds up and slows down four times. Worse if misfiring. The car does its best to match the engine rotation to the rotation of the MGs. What you're calling the "torque plate" is there because the matching can't ever be perfect, but you want it to be close. When it isn't, there is a clanking noise (and the "torque plate" eventually gets beaten up).

 

Yep I got it so maybe the torque plate was beat up or was damaged while it was on the back of the engine which is the one I bought I think my original torque plate and transmission are sitting here in the shed there was nothing wrong with them at time of removal except the engine had thrown a rod from the head gasket business which cracked the center girdle which is the reciprocating mass and ruin that motor. So like I say I'm at the point where apparently the transmission has to come out another expense on a car that shouldn't have any money be spent on it at this point as far as I'm concerned but just to see if I could run the engine without the transmission connected I am more or less positive that the engine will sit there and run just wonderfully there is no missing no fire being put out none of that it just runs and throughout the RPM range quite well too just runs like every other Toyota engine I've owned before it just runs funny how in the old days of the 22 are in a distributor I don't think I had a missing any of those engines for 16 years or some run like that never plug soaked in oil you name it never skip the beat wires ancient old is all get out 22R and a truck or a celica. Never miss the beat till the engine went something like that these newer cars man you can't do anything without some kind of misfire code which many times the misfire is not the ignition system It's the fire being extraneously put out like by water.