Hesitation on Acceleration
10-25-14, 03:14 PM
#61
Im starting to like the oil filter or oil screen theory.
If this issue is starting right after a fresh oil change it makes sense because isn't that when the oil would be at its thickest and most viscous?
After a few hundred miles its been heated , its been filtered , its been thinned out to some extent and then maybe the car starts to run as normal again.
Has anyone tried that engine cleaner stuff I used to hear about in every second thread in the sc400 section .....seafoam ??
If this issue is starting right after a fresh oil change it makes sense because isn't that when the oil would be at its thickest and most viscous?
After a few hundred miles its been heated , its been filtered , its been thinned out to some extent and then maybe the car starts to run as normal again.
Has anyone tried that engine cleaner stuff I used to hear about in every second thread in the sc400 section .....seafoam ??
10-25-14, 04:14 PM
#62
How does the car know its oil has been changed if we don't tell it by resetting the oil change required alert? If it doesn't, then the simple test would be to change the oil at, say, 2,500 miles instead of 5k miles, DON'T tell the car about it, and see if the hesitation manifests. Alternatively, DON'T change the oil when "Maintenance Required" appears, but tell it you did (via reset procedure). See if the hesitation manifests.
If one CL member would do the first and one the second, we should have our answer...
If one CL member would do the first and one the second, we should have our answer...
10-25-14, 04:26 PM
#63
Pole Position
I wonder if the previous owner was a user of conventional oil or didn't change the oil religiously? I know you use the toyota synthetic, but maybe the other guy was just using regular 5w20.
10-25-14, 05:02 PM
#64
How does the car know its oil has been changed if we don't tell it by resetting the oil change required alert? If it doesn't, then the simple test would be to change the oil at, say, 2,500 miles instead of 5k miles, DON'T tell the car about it, and see if the hesitation manifests. Alternatively, DON'T change the oil when "Maintenance Required" appears, but tell it you did (via reset procedure). See if the hesitation manifests.
If one CL member would do the first and one the second, we should have our answer...
If one CL member would do the first and one the second, we should have our answer...
On the most recent oil change I tried the shotgun approach. Had the re-flash, added some sea foam in the crankcase, then did the oil change using Toyota 0W-20 syn. and an oe filter. Not any hesitation at all since then. I'll add some cleaner to the oil before the next change and use the toyota 0W-20 syn again. I'll post the result.
10-25-14, 05:32 PM
#65
Yup perhaps a switchover from conventional to synthetic (after an extended period of time) can perhaps cause a cleaning of varnish and perhaps cause a VVT problem, but we all know these cars require synthetic from day 1. Now perhaps people have gone to places and they are having regular (unbeknownst to them) oil put in these cars...I could certainly even see a dealer doing this to them. Charge them for synthetic and drop 9 quarts of regular oil in there and eventually it catches up to them when they actually do get synthetic put in there, so that's a possibility I guess.
The thing that doesn't add up is that this seems to be happening at various times...not just right after an oil change. I've read from people that they thought it went away, then it came back. I've read it goes away 200-300 miles after an oil change. Then I've read it returns a few weeks later on some others. I think a possibility exists that it has nothing to do with oil all together, but what you are saying does make some sense.
So let me ask you this, have you ever seen a dirty transmission filter cause acceleration/hesitation problems? I have and considering this transmission is a "lifetime" fluid type, I can easily see how these filters get neglected. And think of all the clutch material that is in a 8 speed transmission...then remember how much this car weighs and the wear of that material that occurs to slow this thing down, or get it up a hill. The thing is constantly shifting. That clutch material has to go somewhere, most likely it's in the filter. Hey it's just another way to look at it.
I will say this, the week after I bought this car I would mash the gas pedal just to see what it had for power...there would be a hesitation before the thing took off like a rocket. I have since changed the tranny fluid and filter and I don't think it's there anymore. Then again my car wasn't doing what was in that youtube video.
The thing that doesn't add up is that this seems to be happening at various times...not just right after an oil change. I've read from people that they thought it went away, then it came back. I've read it goes away 200-300 miles after an oil change. Then I've read it returns a few weeks later on some others. I think a possibility exists that it has nothing to do with oil all together, but what you are saying does make some sense.
So let me ask you this, have you ever seen a dirty transmission filter cause acceleration/hesitation problems? I have and considering this transmission is a "lifetime" fluid type, I can easily see how these filters get neglected. And think of all the clutch material that is in a 8 speed transmission...then remember how much this car weighs and the wear of that material that occurs to slow this thing down, or get it up a hill. The thing is constantly shifting. That clutch material has to go somewhere, most likely it's in the filter. Hey it's just another way to look at it.
I will say this, the week after I bought this car I would mash the gas pedal just to see what it had for power...there would be a hesitation before the thing took off like a rocket. I have since changed the tranny fluid and filter and I don't think it's there anymore. Then again my car wasn't doing what was in that youtube video.
There was no scam in regard to having regular oil changes from the dealer. Pre- 2012 many of the Lexus vehicles were getting regular Toyota 5W-30 oil. It is only after 2012 or so that Toyota has been on an aggressive campaign pushing their 0W-20 synthetic. What I can speculate is that those people that were getting their cars serviced from Lexus probably made the change when they have accumulated enough deposits from the dino oil.
It has been observed on other engines that use the same type of VVT actuators that they too run into the same problems. Not all and not every engine or every car is going to have exactly the same issue but you can draw some loose conclusions.
Case in point.
http://www.corolland.com/forums/inde...eration/page-2
Having owned both a 1ZZ and a 2ZZ these were typical issues faced by owners who changed to synthetic oil. In fact in some cases changing to synthetic oil late in the game can unmask issues and can cause a catastrophic failure with oil gallery occlusions. So it begs the question why cant this small screen not suffer a similar fate being a little more sensitive to deposit formation.
In regard to the transmissions, it is normal for the car to delay shift. It could possibly shift faster but I suspect Toyota intentionally did this for reliability. Other cars with SMT type transmission that shift quickly are the most prone to break. When Toyota made their first production SMT it shifted very slow. I suspect they were looking at the longevity aspect compared to the Europeans.
In regard to the trans filter I doubt it's nothing more then an artifact that is there to trap some metal shavings during the initial break in. I highly doubt the high pressure of the transfulid goes though that filter and its most likely bypassed and passive.
Last edited by Devh; 10-25-14 at 05:53 PM.
10-25-14, 05:44 PM
#66
Im starting to like the oil filter or oil screen theory.
If this issue is starting right after a fresh oil change it makes sense because isn't that when the oil would be at its thickest and most viscous?
After a few hundred miles its been heated , its been filtered , its been thinned out to some extent and then maybe the car starts to run as normal again.
Has anyone tried that engine cleaner stuff I used to hear about in every second thread in the sc400 section .....seafoam ??
If this issue is starting right after a fresh oil change it makes sense because isn't that when the oil would be at its thickest and most viscous?
After a few hundred miles its been heated , its been filtered , its been thinned out to some extent and then maybe the car starts to run as normal again.
Has anyone tried that engine cleaner stuff I used to hear about in every second thread in the sc400 section .....seafoam ??
This is not a viscosity issue. You could run this car on 40wt oil and it would have no issues.
When adding new synthetic oil, it's cleaning due to the esters and detergent additives which can be quiet aggressive initially. What happens is dyno oil varnish deposits as well as carbon gets stripped but not dispersed. These plaque like substances find their way to the oil filter screen on the VVT actuators reducing flow, pressure or both. Once the oil settles down the deposits liquefy and pass though the screen.
This problem will persist until the old dino deposits are cleaned by the synthetic oil or until the car gets a good engine flush that is of the dispersion type, not the crap you get in your typical auto parts store.
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DrQuality (08-07-21)
10-25-14, 05:49 PM
#67
Pole Position
Two thoughts here.
There was no scam in regard to having regular oil changes from the dealer. Pre- 2012 many of the Lexus vehicles were getting regular Toyota 5W-30 oil. It is only after 2012 or so that Toyota has been on an aggressive campaign pushing their 0W-30 synthetic. What I can speculate is that those people that were getting their cars serviced from Lexus probably made the change when they have accumulated enough deposits from the dino oil.
It has been observed on other engines that use the same type of VVT actuators that they too run into the same problems. Not all and not every engine or every car is going to have exactly the same issue but you can draw some loose conclusions.
Case in point.
http://www.corolland.com/forums/inde...eration/page-2
Having owned both a 1ZZ and a 2ZZ these were typical issues faced by owners who changed to synthetic oil. In fact in some cases changing to synthetic oil late in the game can unmask issues and can cause a catastrophic failure with oil gallery occlusions. So it begs the question why cant this small screen not suffer a similar fate being a little more sensitive to deposit formation.
In regard to the transmissions, it is normal for the car to delay shift. It could possibly shift faster but I suspect Toyota intentionally did this for reliability. Other cars with SMT type transmission that shift quickly are the most prone to break. When Toyota made their first production SMT it shifted very slow. I suspect they were looking at the longevity aspect compared to the Europeans.
In regard to the trans filter I doubt it's nothing more then an artifact that is there to trap some metal shavings during the initial break in. I highly doubt the high pressure of the transfulid goes though that filter and its most likely bypassed and passive.
There was no scam in regard to having regular oil changes from the dealer. Pre- 2012 many of the Lexus vehicles were getting regular Toyota 5W-30 oil. It is only after 2012 or so that Toyota has been on an aggressive campaign pushing their 0W-30 synthetic. What I can speculate is that those people that were getting their cars serviced from Lexus probably made the change when they have accumulated enough deposits from the dino oil.
It has been observed on other engines that use the same type of VVT actuators that they too run into the same problems. Not all and not every engine or every car is going to have exactly the same issue but you can draw some loose conclusions.
Case in point.
http://www.corolland.com/forums/inde...eration/page-2
Having owned both a 1ZZ and a 2ZZ these were typical issues faced by owners who changed to synthetic oil. In fact in some cases changing to synthetic oil late in the game can unmask issues and can cause a catastrophic failure with oil gallery occlusions. So it begs the question why cant this small screen not suffer a similar fate being a little more sensitive to deposit formation.
In regard to the transmissions, it is normal for the car to delay shift. It could possibly shift faster but I suspect Toyota intentionally did this for reliability. Other cars with SMT type transmission that shift quickly are the most prone to break. When Toyota made their first production SMT it shifted very slow. I suspect they were looking at the longevity aspect compared to the Europeans.
In regard to the trans filter I doubt it's nothing more then an artifact that is there to trap some metal shavings during the initial break in. I highly doubt the high pressure of the transfulid goes though that filter and its most likely bypassed and passive.
What you are saying makes sense regarding the hesitation, and if that's the case, then for all the people that have it it's no major problem.
10-25-14, 05:51 PM
#68
If the car was never changed to synthetic I imagine it would not manifest this problem until a lot of miles have accumulated.
There is a lot of hype surrounding synthetic oil but one of the biggest overlooked benefits is the cleanliness of the engines.
10-25-14, 06:00 PM
#69
Makes sense. I've got to say I've never heard of fluid being bypassed in a transmission filter...oil filter? Yes, but never in a transmission filter, but I guess that could be the case obviously in strainer type filters, but the LS has the paper element style like we usually would see in an older car.
What you are saying makes sense regarding the hesitation, and if that's the case, then for all the people that have it it's no major problem.
What you are saying makes sense regarding the hesitation, and if that's the case, then for all the people that have it it's no major problem.
I have seen some manufactures use some sort of catch screen during the initial break in of product and then it just ends up being a remnant. Since the transmission is sealed and once the gears are seated there should not be much contamination or excessive wear that warrants it's change for the effective service life of the car.
10-28-14, 08:14 PM
#70
Premature Celebration
so i finally did the first oil change in the car - took it to the quick lube and was in and out in 20 minutes. Didn't notice anything driving home. The next day, the hesitation was back in full force and that continued for another few days (i was seeing if it would work itself out). 
finally tonight i took some cl members' advice and took the battery terminals off and connected them electrically to one another using a piece of aluminum wire. This was all very uneventful. I re-connected everything and took the car out for a ride and there was no hesitation any more.
This got me thinking that when i bought my car, carmax performed an oil change on it, and this might have been all it needed to clear up my issue.
I'll post again if the issue returns before the next oil change. If you don't hear from me, i'll be driving merrily along!
finally tonight i took some cl members' advice and took the battery terminals off and connected them electrically to one another using a piece of aluminum wire. This was all very uneventful. I re-connected everything and took the car out for a ride and there was no hesitation any more.
This got me thinking that when i bought my car, carmax performed an oil change on it, and this might have been all it needed to clear up my issue.
I'll post again if the issue returns before the next oil change. If you don't hear from me, i'll be driving merrily along!
10-28-14, 08:29 PM
#71
Musings on oil vs. the oil change process...
It's not being by passed per say but it's probably passing though the filter with reduced pressure.
I have seen some manufactures use some sort of catch screen during the initial break in of product and then it just ends up being a remnant. Since the transmission is sealed and once the gears are seated there should not be much contamination or excessive wear that warrants it's change for the effective service life of the car.
I have seen some manufactures use some sort of catch screen during the initial break in of product and then it just ends up being a remnant. Since the transmission is sealed and once the gears are seated there should not be much contamination or excessive wear that warrants it's change for the effective service life of the car.
One thing that happens during an oil change is that some of the passageways that are normally full of oil get drained (like the filter element for example). Then, when we re-fill the pan with oil and start up the engine, there will be some amount of time where these "air bubbles" need to get pushed through the system to make way for the oil. The TSB specifically mentions knock sensor indications (and when an engine knocks, the computer retards the timing to prevent additional future preignition). So basically I am wondering if during the timeframe when we start up the engine after an oil change if the hydraulic valve lash adjusters or some of the other fancy hydraulic bits "clickity clack" and cause the knock sensors to make the engine controller retard the timing under various driving conditions, generally annoying us all.
10-29-14, 01:43 AM
#72
I find all of this discussion on oil varieties, deposits etc. confusing because the re-flash of my engine computer fixed the problem so instantly and permanently (until the next oil change) that I am currently convinced the problem occurs right at the time of the oil change and then needs to be corrected in the computer.
When we re-fill the pan with oil and start up the engine, there will be some amount of time where these "air bubbles" need to get pushed through the system to make way for the oil. The TSB specifically mentions knock sensor indications (and when an engine knocks, the computer retards the timing to prevent additional future preignition). So basically I am wondering if during the timeframe when we start up the engine after an oil change if the hydraulic valve lash adjusters or some of the other fancy hydraulic bits "clickity clack" and cause the knock sensors to make the engine controller retard the timing under various driving conditions, generally annoying us all.
When we re-fill the pan with oil and start up the engine, there will be some amount of time where these "air bubbles" need to get pushed through the system to make way for the oil. The TSB specifically mentions knock sensor indications (and when an engine knocks, the computer retards the timing to prevent additional future preignition). So basically I am wondering if during the timeframe when we start up the engine after an oil change if the hydraulic valve lash adjusters or some of the other fancy hydraulic bits "clickity clack" and cause the knock sensors to make the engine controller retard the timing under various driving conditions, generally annoying us all.
When you have a cleared computer then you start building a table for both short term fuel trims and long term fuel trims but initially it will use the factory tables which the ignition is a little more advanced. During this period and the car will appear to be peppier until the fuel tables settle down to what is most fuel efficient and emission friendly which means you lose some in the process. If you have an underlying sensor issue then it will present it's self as a sluggish car.
The lubricating system works by the geared pump to give immediate oil pressure. Even if the oil filter is empty it quickly fills up and is bypassed when its under pressure so that oil gets pumped to the peripheries. Any good oil has antifoaming agents that disperse bubbles and there is splash lubrication in the valvetrain that is not under any pressure. If there was major foaming you would also have rod knock.
Hydraulic valves generally retain oil however if a car has not been started in a very long time then there is the possibility of the lifters needing to be primed with oil and it may tick on initial start up, from what I can tell this car doesn't seem to have that problem and if it did, it would be clearly heard.
Also the car is sophisticated to know the difference between true knock and false knock. Valvetrain noise or even unusually loud noises from the valve train are filtered and usually do not register as knock.
For argument sake even if the knock sensor picked up true knock it would only retard timing a little as if the car was not running premium fuel and the power decrease would not be dramatic.
If the engine detects a great deal of knock to cause extreme hesitation that people describe then car would go into limp mode and that hasn't really happened.
Last edited by Devh; 10-29-14 at 03:43 AM.
10-29-14, 09:52 AM
#74
You are most welcome. Please don't take my words as gospel as it should be challenged and verified as it's just my opinion.
I spend a great deal of time with every aspect of my other car and the cars before it including tuning the damn thing with a wideband and a sophisticated tuning software that has taken a year to understand the subtitle nuances.
I spend a great deal of time with every aspect of my other car and the cars before it including tuning the damn thing with a wideband and a sophisticated tuning software that has taken a year to understand the subtitle nuances.
10-29-14, 10:44 AM
#75
No better way to understand a system than direct control of the variables that control its behavior. I wish I had the smarts to do tuning, but my control systems training is a LONG time in the past.