Serious Engine Knock less than 4000 miles brand new, done with Toyota

In another video on youtube it sounded the same. The guy obviously has it frequently enough he predicted easily before taking the vid that it would happen and it did. My wife had it happens the one time in ours, says the video sounded like that but admits it was so long ago she's not sure.

Where is Bob's poll? And don't be impolite with the answer

 

Here's the link:

http://priuschat.com/forums/gen-iii.../86722-1-8l-starting-rattle-knock-events.html

with my best regards! (polite enough?)

 

Thanks

 

I responded to the poll, and I have never experienced this. I did experience maybe a handful of times on my '88 CRX-Si, a very rough engine start that went away after a few seconds, with all occurrences between 300,000 and 400,000 miles.

This Prius rough engine start has me tempted to try to create it by moving the car at night and shutting it off in the garage before it completes the initial warmup cycle, then seeing what happens the next morning.

 

FWIW on another vehicle of mine years ago in, I think cold weather, I once started it up and drove it a couple of car lengths then later on went back to it and it started really rough. I had assumed that it was running very rich for a few seconds based on my earlier start without it being properly warmed up but that was a pure guess and it never recurred. I recall more a shuddering type thing than knocking but my memory is crap and it was years ago

 

I noticed a drop in mpg when using Shell V-Power (the UK high octane one) compared to Normal Shell Unleaded, not worth the extra cost IMO.

 

Hey, all,

I thought I'd let you in on another thread that some of you may have overlooked. The first post is by a Toyota tech as indicated immediately under his username. I know the noise some owners experience is far longer than one second, but this info may begin to explain what may be going on & there may be a TSB for it by this time (his post was from back in June). Here's the link to the other thread. I hope it works.

http://priuschat.com/forums/gen-iii...nocking-noise-startup-there-may-hope-yet.html

Ken (in Bolton,Ct)

 

Sure sounds like fouled spark plugs. It -might- be bad coil packs, but that remains to be seen. First guess for me is spark plugs. Especially when several owners reported it -after- they moved the car without warming it up AND it "fixed itself" after they either reved the engine or warmed it up. Start it up and shut it down will cause some fuel to be left in the combustion chamber. Start it again some time later and it's running -very- rich.

Yes, you CAN foul iridium plugs. You just have to try hard enough. Been there, done that.

Oh, and yes, one or two cylinders not firing WILL sound like the engine is toast! It WILL NOT damage the engine!

 

why don't you turn on the heater, keep your car warm.

 

You know FWIW I read in my manual today it says some knocking during heavy acceleration or up inclines is normal and ok. Strange. Anyway, I realize the knocking mentioned here and elsewhere is start-up knocking.

 

I disagree - it sounds more like the valve gear before it gets fully lubricated. You can hear the knock come and go very much as it would when the tappets rotate (they are usually arranged to rotate to even out wear).

kevin

 

Holy smokes, man, I am a noob + here, but I have a prescription before you actually do cause damage to your Prius: take a few calming, deep breaths and "RTFM*".

*Read the "flaming" manual.

 

Or, read the fine manual.

 

Wondering if it could also be a VVT issue? That is, cold start the VVT position valve may stick. Some VVT motors are especially sensitive to oil viscosity especially when cold

 

No way valve gear causes violent knocking, me thinks.

People had experienced this knocking after starting the Prius and moving it a few feet (no knocking), stop the ICE, then restart, then knocking happens. You'd think the valve gear's not lubricated the 1st time, not the 2nd time.

 

If it's due to VVT in cold oil, I'd imagine it would happen to many cars too, not just he Prius genIII, especially those with "thicker" oils. But no, it only happens to genIII with 0W20 oil, the thinnest oil I've ever heard?

 

Yeah 0w synthetic should be able the easiest oil possible to get going when cold. And these are not Alaskan temperatures, I had the knocking in July, so it was way above freezing.

 

Unbelievably, we had knocking this morning, 9k after first event. Will update in the poll thread.

 

If it's vvt or poor lub you'd think it'll happen every morning. But in your case it happened 9k apart, just enough carbon accumulation in between, I think. Once the carbon deposits are "coughed" off by the knocking, it'll probably last another 9k.

Maybe you're a good candidate to test this "German tune-up" technique? Floor it once in a while and see if this knocking comes back again 9k later?