Hey all, I'm new to this forum and noticed that many people have received helpful answers here. I currently have a problem with my 2010 rx 450h lexus, where the engine part would start shaking very noticeably when I turn it on. I have taken it to the local shop, and have replaced all 6 coils at their suggestion but the problem persists. Now they're saying that it might have to do with something behind the transmission. I was wondering if anybody has any experience with this type of problem?

 

Does it go away after warm up? We had cold start up shaking discussed in depth at toyotanation in Camry Hybrid section. I experienced it many times on my Camry Hybrid. Well, maybe 5-6 times. Always at cold start up always goes away as engine warms up.
No one really knows why. We had theories. Mine is low oil pressure. I finally had my Camry engine rebuilt for oil consumption by dealer, as it failed oil consumption test. I am not aware of same situation for V6 engines though.
So doe sit go away as it warms up or not?
Also, do NOT touch accelerator to rev engine when it's doing this.
You mechanic is guessing on cause, by the way. Afraid they are milking you.

 

if it shakes all the time then you need a new motor mount somewhere

 

It doesnt matter when we turn the car on, we can have it running and then turn it off before turning it back on right away and it will still shake. It does go away after a minute or two, but in that time it has a very loud noise while shaking.

 

Sounds a lot like the symptoms described on this thread:
https://www.clublexus.com/forums/hybrid-technology/669026-6-new-fuel-injectors-and-1400-worth-of-warranty-work.html

Do you use premium gasoline, just out of curiousity?

 

I do! I've never used anything less than the premium gasoline. I have checked out that link and it might be the cause of it. Would you happen to know how to take the fuel injectors out of a rx450h in order for me to manually clean it myself? Or is this a problem that I would need to take to the mechanic.

 

Premium gas is supposed to have the cleaning additives to help keep the insides of the injector clean. Assuming this is happening, then the only explanation is that the injectors are getting dirty on the outside, not the inside.

This contamination is quite likely due to the EGR system, specific to the RX450h. The RX350 does not seem to suffer from this issue, probably because it doesn't have an EGR system.

​​​​​i don't believe that the injectors are easily removable for cleaning or replacement. Sorry I don't know enough to give you a recommendation for remediation.

 

My 2013 RX450h is with the dealer for the exact problem! As tempestv8 stated and had provided a link, it's the fuel injectors. The dealer just called me earlier to tell me that the cost would be about $2000 since the car is out of warranty. It has about 35,000 miles, always premium gas from BP or Mobil, and oil and filter change every 3500 miles.
My wife drives a 2008 RX400h with about 95,000 miles on it without such problem!

 

Did the dealership show you the old injectors?

Also, did they offer an explanation as to why the injectors needed to be replaced so soon?

Is there any recommendation given by the dealer on how to avoid a repeat of this issue?

 

They told me even though they say 93 octane at gas stations, but the gas will not be 100% as they claim. I believed the problem had been the fuel Injectors from the thread I read somewhere on this forum but not sure why this would happen on a Lexus hybrid and it's a third gen. Like I have mentioned before, wife's 2008 400h has around 96,000 miles and never had this problem. Same gas from the same station. Thanks.
By the way, after the dealer replaced all injectors the car is good now with no vibration and noise. I also notice a slight better fuel economy.

 

The low mileage usually means lots of short trips and that could cause more junk to build up, maybe you got some dirty gas that the 400h didn't get.
Either way you are out of warranty.

There is not much you can now, but to prevent it in the future, I recommend you run injector cleaner once a year. Seafoam is my preference, I prefer to add it when doing a long road trip where you plan to burn out the tank fairly quickly. I'm at 115k and haven't had this issue as yet but I was aware of it, hence me using injector cleaner once per year to hopefully prevent it, so far so good (knock on wood).