I usually keep the IS in the garage but with the holiday commotion in/out of the attic I decided to park in the driveway over the last 5 days while it just sat. I go to start it this afternoon and the thing began to shake like a crack addict on a 48 hr withdrawal. Basically felt like a cylinder dropped out. It took the better part of the warm-up for the engine to regain it's familiar purr but damn REALLY?!!!!

I've noticed in the past that when sitting idle for more than 2 days or so that the engine has an excessively violent start up kinda like a big block V8 does as it shakes the entire car side to side for a few rev's on initiation. Always purring just after though.

This is the first time I've felt a cylinder drop out (i.e. foul out) like this. First thing I did after a proper warm up was to get on the pipe a few times at stop lights and highway on-ramps. It's been fine since but I gotta wonder, is that carb build up issue starting to creep in? I only drive her a few times per week at most so I've tried to be good about clearing her throat at least once or twice every time I get her out of the stables. Hmmmm, wtf?!!!

 

had this once at about 12k miles for a split second, hasnt happened since and im at 30k, mayb someone who knows more can enlighten us

 

Had this happen to me after i came back from vacation after 30 days.

 

Same thing happened to me! I parked the car away for 5 days, started it up, the damn thing did exactly what you described! I'm guessing its something carbon build up related..?! Went away immediately once I started driving though and no issues since.

 

had the similar problem with mine.. my car was parked outside in the cold for 12hours and when i started it up something in the engine was vibrating/ clicking not the normal click for like 2-3 seconds.. im still trying to figure what went wrong, hopefully nothing bad..

 

Are all of your cars IS250s? I only drive my car 3-4 days a week and no shaking. IS350.

 

^ Mine's a 250. I have no issues if i don't drive my car for a weekend, but it seems when its stored for longer than that, the shaking OP described seems to happen...

 

if it is carbon build up try running some seafoam through your engine

 

I'm thinking this might be a slightly clogged fuel injector. Gonna try some Redline.

 

got my tsb done for the carbon buildup but now its happening again so going to take it to the dealer tomorrow

 

same thing happend to my IS250 2007, I went to start it up one morning it hadnt been started for about 3 days and it was about 30degrees outside, could would attempt to start up but would just sputter and kick like a old pickup that needed to give it some gas...tried it too more times same thing. finally 4th attempt it turned on but was running real shakey idle was just floating ...finally it corrected itself...drove it straight to lexus they stated the "Carbon BuildUp" issue and cold weather would make seem worse. so they cleaned out my engine of carbon buildup and inspected pistons for damage and would do you know...theres damage to my pistons from carbon buildup i guess....apparently theres a TSB on this issue...long story short. My car has been at lexus for about 6 days getting new pistons put in and basically a rebuild of my engine at 57k...all from lexus...YIPPEEE!!!, one more thing if you guys have ever noticed when you come to a stop and your car idles rough then corrects itself...thats carbon buildup..let the dealership know about this.

 

You IS250 and 250c (2006-2010) owners need to read TSB L-SB-0068-11. We have done the piston swap in about 10 IS so far and more waiting to get in the shop. Engine and tranny comes out, engine gets a tear down and new pistons and rings go in, then it all goes back together. takes days to do.

 

Damn, that's freakin wild! So it only seems to be the 250's?

This thread caught my eye and even made me kind of chuckle when I read the title because when I first moved out to Japan, I started my car and felt a VIOLENT rumble. It freaked me out and was worried something was wrong with my car all day until at dinner, I heard some younger Marines talking about how bad the earthquake had been earlier that day...haha. Quite a funny way to experience my first quake, if I do say so myself...

 

I just had my piston swap done. I read the TSB. The piston rings seemed to be changing to the ring that come on the 2011-2012 model IS250. Since the piston rings are reducing the clearance between the piston and the cylinder, increasing friction and such, is that why lexus switched to synthetic 0w20 for the 2011-2012 year rather than the 5w30 recommendation for the 2006-2010 IS250. I am just wondering because the OCI is also 10,000 instead of 5,000 and that would save some of us some money on oil if we could switch. For those of us comfortable with OCI as long as 10,000 miles.

TSB L-SB-0068-11 attached below for reference

 

My car is at the dealership right now getting the pistons replaced per the TSB. I took it in last Wednesday and it is supposed to be ready tomorrow. It's a 2007 IS250 with just under 47k miles on it. The service manager knew exactly what the issue was when I took it in and it is all being covered under the powertrain warranty. No questions asked.