Hesitation on Acceleration
08-16-15, 10:12 PM
#211
Logger
Funny you should mention that. My logger arrives in the mail tomorrow ;-)
I think the best thing to do is data log and when the event occurs you can then see what has transpired.
If knock is observed which retards timing then it could very well be this issue.
If timing is retarding or not advancing as it should in the absence of knock then it;s possibly the VVT.
You should data log using a blue tooth adapter and a laptop or smart phone.
If knock is observed which retards timing then it could very well be this issue.
If timing is retarding or not advancing as it should in the absence of knock then it;s possibly the VVT.
You should data log using a blue tooth adapter and a laptop or smart phone.
08-17-15, 09:21 AM
#212
Logging has pointed me in the right direction but one needs to be careful because it can lead you in the wrong direction because everything works in tandem with each other.
08-17-15, 11:39 AM
#214
I have thought about this also because I notice that when the car is cold I can go around a corner while in second gear and at 2000 rpm's and hit it and there is no hesitation at all, its only when the car is up to temp.? Also as I have mentioned before when the hesitation was almost gone at one point, the wife and I did a day trip in stop and go traffic in hot weather, after that the hesitation was back completely ?? It took a couple of days for little to no hesitation too return. Again I only use Sunoco 93 octane.
08-17-15, 11:45 AM
#215
I hear that.
I have thought about this also because I notice that when the car is cold I can go around a corner while in second gear and at 2000 rpm's and hit it and there is no hesitation at all, its only when the car is up to temp.? Also as I have mentioned before when the hesitation was almost gone at one point, the wife and I did a day trip in stop and go traffic in hot weather, after that the hesitation was back completely ?? It took a couple of days for little to no hesitation too return. Again I only use Sunoco 93 octane.
08-17-15, 03:15 PM
#216
Pole Position
So I have been silently working on a test of my own. Testing different brands of fuel. Still got many months left to go in order to prove theory
But the reason I say fuel would be from three causes
1. Carbon build up. Very easy Google search will tell you direct injection doent spray fuel on certain parts and therefore don't get cleaned by the fuel. Many manufactures are awhere of these problems and even have TSB's. Plenty of information on the web. Just very hard to prove, but you could pull the top of your engine off and see
2. Ethanol in fuel. There is a lot going on when your car ignites the fuel, and the car makes adjustments based on the fuel burning process. Again, there is a lot of debate on how bad ethanol is for your car. A good rule is to never use more than 10% and try finding 100% pure gasoline and see if this problem continues. Could be hard to find in your area. A Google search and you can find stations who have pure gasoline. It also will cost a bit more.
3. Fuel quality. This is my little project I am working on. Everyone has heard of top teir gasoline and should be using it. We are driving one of the most advanced engine on the road, put the good stuff in there. Find one of these fuel brands and stick with it for months. Don't just buy fuel from any place. Get a routine. If you can, find a store that is rather new and hopefully the fuel storage system should be in cleaner condition. Fuel quality starts at the manufacture and continues all the way through the pump.
But the reason I say fuel would be from three causes
1. Carbon build up. Very easy Google search will tell you direct injection doent spray fuel on certain parts and therefore don't get cleaned by the fuel. Many manufactures are awhere of these problems and even have TSB's. Plenty of information on the web. Just very hard to prove, but you could pull the top of your engine off and see
2. Ethanol in fuel. There is a lot going on when your car ignites the fuel, and the car makes adjustments based on the fuel burning process. Again, there is a lot of debate on how bad ethanol is for your car. A good rule is to never use more than 10% and try finding 100% pure gasoline and see if this problem continues. Could be hard to find in your area. A Google search and you can find stations who have pure gasoline. It also will cost a bit more.
3. Fuel quality. This is my little project I am working on. Everyone has heard of top teir gasoline and should be using it. We are driving one of the most advanced engine on the road, put the good stuff in there. Find one of these fuel brands and stick with it for months. Don't just buy fuel from any place. Get a routine. If you can, find a store that is rather new and hopefully the fuel storage system should be in cleaner condition. Fuel quality starts at the manufacture and continues all the way through the pump.
08-17-15, 04:57 PM
#217
So I have been silently working on a test of my own. Testing different brands of fuel. Still got many months left to go in order to prove theory
But the reason I say fuel would be from three causes
1. Carbon build up. Very easy Google search will tell you direct injection doent spray fuel on certain parts and therefore don't get cleaned by the fuel. Many manufactures are awhere of these problems and even have TSB's. Plenty of information on the web. Just very hard to prove, but you could pull the top of your engine off and see
2. Ethanol in fuel. There is a lot going on when your car ignites the fuel, and the car makes adjustments based on the fuel burning process. Again, there is a lot of debate on how bad ethanol is for your car. A good rule is to never use more than 10% and try finding 100% pure gasoline and see if this problem continues. Could be hard to find in your area. A Google search and you can find stations who have pure gasoline. It also will cost a bit more.
3. Fuel quality. This is my little project I am working on. Everyone has heard of top teir gasoline and should be using it. We are driving one of the most advanced engine on the road, put the good stuff in there. Find one of these fuel brands and stick with it for months. Don't just buy fuel from any place. Get a routine. If you can, find a store that is rather new and hopefully the fuel storage system should be in cleaner condition. Fuel quality starts at the manufacture and continues all the way through the pump.
But the reason I say fuel would be from three causes
1. Carbon build up. Very easy Google search will tell you direct injection doent spray fuel on certain parts and therefore don't get cleaned by the fuel. Many manufactures are awhere of these problems and even have TSB's. Plenty of information on the web. Just very hard to prove, but you could pull the top of your engine off and see
2. Ethanol in fuel. There is a lot going on when your car ignites the fuel, and the car makes adjustments based on the fuel burning process. Again, there is a lot of debate on how bad ethanol is for your car. A good rule is to never use more than 10% and try finding 100% pure gasoline and see if this problem continues. Could be hard to find in your area. A Google search and you can find stations who have pure gasoline. It also will cost a bit more.
3. Fuel quality. This is my little project I am working on. Everyone has heard of top teir gasoline and should be using it. We are driving one of the most advanced engine on the road, put the good stuff in there. Find one of these fuel brands and stick with it for months. Don't just buy fuel from any place. Get a routine. If you can, find a store that is rather new and hopefully the fuel storage system should be in cleaner condition. Fuel quality starts at the manufacture and continues all the way through the pump.
In regard to direct injection we have both DI and port which alleviates this condition. If it was a problem then you would see it across the board from other Toyota cars that use the D4-S injection system.
The lack of combustibility of fuel can be seen if the fuel trims are off which I highly doubt it would manifest in any intermittent change. You would also see this condition in every car eventually if this engine was extremely sensitive to fuel quality.
08-17-15, 05:28 PM
#218
Pole Position
Although I agree with using brand name fuel that adds their additives at the pump I highly doubt it's is a fuel quality issue.
In regard to direct injection we have both DI and port which alleviates this condition. If it was a problem then you would see it across the board from other Toyota cars that use the D4-S injection system.
The lack of combustibility of fuel can be seen if the fuel trims are off which I highly doubt it would manifest in any intermittent change. You would also see this condition in every car eventually if this engine was extremely sensitive to fuel quality.
In regard to direct injection we have both DI and port which alleviates this condition. If it was a problem then you would see it across the board from other Toyota cars that use the D4-S injection system.
The lack of combustibility of fuel can be seen if the fuel trims are off which I highly doubt it would manifest in any intermittent change. You would also see this condition in every car eventually if this engine was extremely sensitive to fuel quality.
I just have a hard time buying into the oil as being the culprit. I still say fuel or fuel delivery system.
08-17-15, 05:28 PM
#219
Lexus Fanatic
Update:
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
Last edited by roadfrog; 08-17-15 at 05:35 PM.
The following users liked this post:
DrQuality (08-05-21)
08-17-15, 05:36 PM
#220
Pole Position
Devh, I get where you are coming from on fuel quality, but there are a lot of gas stations that sell fuel a few cents cheaper than the other guys. Sometimes there are reasons why they sell lower prices gas. You wouldn't by a used LS460 from a no name store that looks run down and a bit shady just to save a few bucks. So why do people fill their car at these places to save $1.00 or two. Sure there are good ol gas stations out there and I don't want to debate that. I'm just telling people to fill at the same place and find one that has good results.
08-17-15, 05:53 PM
#221
Pole Position
Chris, have you ever changed your plugs or at least looked at them? Could hesitation be related to a misfire ? Could hesistation be linked to oil consumption ? I know you are set on the oil and hesitation relationship. But still think gasoline related.
As long as this stays civil, forums offer great debate
As long as this stays civil, forums offer great debate
08-17-15, 06:04 PM
#222
Lexus Fanatic
Chris, have you ever changed your plugs or at least looked at them? Could hesitation be related to a misfire ? Could hesistation be linked to oil consumption ? I know you are set on the oil and hesitation relationship. But still think gasoline related.
As long as this stays civil, forums offer great debate
As long as this stays civil, forums offer great debate
Yes, I have changed my spark plugs and my DIY on it (and MAF cleaning) is in the Stickies.
08-17-15, 06:29 PM
#223
Update:
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
Roadfrog, so glad to hear that it's gone. Just so I get this straight, you shut it off with the hesitation then started it two days later and it was gone ???? This really is a head scratcher, this had happened to me before. That's why I mentioned the hesitation gone when I drive it cold because it was there the day before when it was hot ????????
I need a drink !!!!
08-17-15, 06:35 PM
#224
Pole Position
Update:
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
Didn't get a chance yesterday to drive my car again, but I did today.
Hesitation is gone. No hint of hesitation and the car drives as good as it ever did. So in summary, one hour in the day and less than 30 miles of hesitation and then disappeared. Remnants of debris in the VVT-I maybe? Dunno, but glad this episode was a short one and just a hiccup in the 25k miles and over one year since my last episode.
Again, there is NO doubt it's oil related. Either that or it's a complete fluke that immediately after 3 different oil changes that the hesitation occurs, (as is the case with many other members here). If that's coincidence, then we need to buy lottery tickets. As for fuel, my fuel selection has never changed. Pretty regular regimen.
08-17-15, 06:44 PM
#225
You guys really don't believe the knock sensors cause the hesitation? Really seems odd to me not to accept the TSB and the service article. It makes perfect logical sense. Poor fuel quality or dirty injectors will not cause intermittent hesitation as experienced. The knock sensors will retard the timing if you run low octane fuel but it will not cause the car to loose significant power. This is unrealistic thinking.
If you analyze the symptoms not the actual root cause it will lead to misinformation in my opinion. There is only one thing that will cause the engine to significantly loose power as many experience in such an intermittent fashion. This is the knock sensors. What is causing the knock sensors to engage? The improper movement of the valves. The ecu update is a smart choice but it does not actually address the real problem. I do believe the oil question just delays the inevitable. If there is a design defect in the guides this is what needs to be fixed. Oil pressure I am sure plays a role in the movement of the valves but clearly from the articles it is not the root of the problem. Also, it seems to be more of a common problem as the cars age. Does this not support value guide wear?
If you guys are still under warranty I would be taking my LS into the dealer and trying to get the heads replaced.
If you analyze the symptoms not the actual root cause it will lead to misinformation in my opinion. There is only one thing that will cause the engine to significantly loose power as many experience in such an intermittent fashion. This is the knock sensors. What is causing the knock sensors to engage? The improper movement of the valves. The ecu update is a smart choice but it does not actually address the real problem. I do believe the oil question just delays the inevitable. If there is a design defect in the guides this is what needs to be fixed. Oil pressure I am sure plays a role in the movement of the valves but clearly from the articles it is not the root of the problem. Also, it seems to be more of a common problem as the cars age. Does this not support value guide wear?
If you guys are still under warranty I would be taking my LS into the dealer and trying to get the heads replaced.
The following users liked this post:
DrQuality (08-08-21)