LS 460 Acceleration Problems
07-23-12, 07:26 PM
#16
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Well, after three weeks the vehicle has been returned to me. Work was all done under the powertrain warranty of 70,000 miles.
The invoice states:
"Valve shafts worn causing knock sensors to retard timing due to noise. Per Tas verified proper mounting of high pressure fuel pumps and remove drive belt to road test. Vehicle still hesitates. Per FTS replace all valves, cylinder heads, and valve spring seats (Updated parts).
Replaced parts and road test to verify no further hesitation present".
This is essentially a repeat of the work done a month previously, except this time they used all new parts.
It took a few weeks after the last repair for the problem to manifest again. We will see what happens this time. Hopefully this will take care of the issue .
Incidentially, Consumer Reports gives the 07LS a negative black dot for major engine issues.
The invoice states:
"Valve shafts worn causing knock sensors to retard timing due to noise. Per Tas verified proper mounting of high pressure fuel pumps and remove drive belt to road test. Vehicle still hesitates. Per FTS replace all valves, cylinder heads, and valve spring seats (Updated parts).
Replaced parts and road test to verify no further hesitation present".
This is essentially a repeat of the work done a month previously, except this time they used all new parts.
It took a few weeks after the last repair for the problem to manifest again. We will see what happens this time. Hopefully this will take care of the issue .
Incidentially, Consumer Reports gives the 07LS a negative black dot for major engine issues.
08-08-12, 05:27 PM
#17
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i have the same issue with my LS460 2009 awd...today i called the dealer and told him my symptoms and that they started happening shortly after a 70.000km maintenance service.After 5 minutes on the phone they told me theyre ordering new cylinder heads for me straight from Japan (it'll be a few weeks) and it is going to be a 4-5 day repair ... funny thing is they didn't even ask to test drive a vehicle to replicate the problem i described on the phone!
08-10-12, 07:55 PM
#18
wow sebastian, if lexus found out they are going to do that repair without verification, your dealer would be in large trouble. there are several things that can cause that problem. knock correct learn value is reduced to a very low level. this causes the problem. many things can cause that. most common by far = bad gas. ls460 is very sensitive to it.
08-13-12, 06:17 AM
#19
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well, the dealer has tried the "it's the gas routine" we said "ok, we will give that a try" bought gas for several weeks from Exxon, then a couple of weeks from Shell and so on....exact same issue. Westside Lexus in Houston, Texas does not want to pay for the expense repair. We have taken in video after video and same comment each and every time...sorry we can't replicate. They don't even change their line. Call corporate, just as worthless as Westside...can we fight this via Lemon Law or attorney? Or is Toyota just too big? We want a Lexus LS460 that performs like it should, we've been driving Lexus vehicles for 15 years and we are shocked that they just don't care.
08-13-12, 07:05 AM
#20
well, the dealer has tried the "it's the gas routine" we said "ok, we will give that a try" bought gas for several weeks from Exxon, then a couple of weeks from Shell and so on....exact same issue. Westside Lexus in Houston, Texas does not want to pay for the expense repair. We have taken in video after video and same comment each and every time...sorry we can't replicate. They don't even change their line. Call corporate, just as worthless as Westside...can we fight this via Lemon Law or attorney? Or is Toyota just too big? We want a Lexus LS460 that performs like it should, we've been driving Lexus vehicles for 15 years and we are shocked that they just don't care.
08-21-12, 03:15 PM
#21
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Acceleration Problem fixed
I had my oil changed and the acceleration problems began. The tach was accelerating and the car was not going anywhere. So I went to the best place to find out the fix. Yes, club lexus. After I read this thread I made an appointment with Northside Lexus in Houston to address this problem. I have had several bad experiences with Northside but I thought I would give them a try again. It has been two years since I went there. Westside and Northside are owned by the same people. They reasurred me that there were all new people in service.( and that they will just love me. Please let us address your lexus problems. Yea, it seems like I have heard that before) I printed both TSBs and took them with me. I showed the service lady both TSBs. She said she has never seen these TSBs before but will show them to the service dept. I left the car there on Friday and I just picked up the LS today (Tuesday) with both TSBs services done. Drove around all day today and no problems so far. The service dept did not know of these two TSBs to address the acceleration problems until I showed them the printed copies from this site. Maybe they should read the club lexus posts, so they will know how to fix our problems. I will let you know if there are any acceleration changes in my LS.
jarm
jarm
Last edited by jarm; 08-21-12 at 03:19 PM.
08-21-12, 04:39 PM
#22
I had my oil changed and the acceleration problems began. The tach was accelerating and the car was not going anywhere. So I went to the best place to find out the fix. Yes, club lexus. After I read this thread I made an appointment with Northside Lexus in Houston to address this problem. I have had several bad experiences with Northside but I thought I would give them a try again. It has been two years since I went there. Westside and Northside are owned by the same people. They reasurred me that there were all new people in service.( and that they will just love me. Please let us address your lexus problems. Yea, it seems like I have heard that before) I printed both TSBs and took them with me. I showed the service lady both TSBs. She said she has never seen these TSBs before but will show them to the service dept. I left the car there on Friday and I just picked up the LS today (Tuesday) with both TSBs services done. Drove around all day today and no problems so far. The service dept did not know of these two TSBs to address the acceleration problems until I showed them the printed copies from this site. Maybe they should read the club lexus posts, so they will know how to fix our problems. I will let you know if there are any acceleration changes in my LS.
jarm
jarm
08-26-12, 06:30 PM
#24
The Lexus southern area office has informed us that this is popping up all over the nation and that they really don't know what it is yet. Same issue, typical oil change and then accel. complaint. The land of the rising sun engineers will be coming over for this one.
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barloewen (11-29-22)
08-26-12, 07:00 PM
#25
A written complaint, regarding this issue, has recently been sent to the NHTSA safercar.gov site.
You can read the pdf file here: http://www-odi.nhtsa.dot.gov/acms/cs...61521-9280.pdf
You can read the pdf file here: http://www-odi.nhtsa.dot.gov/acms/cs...61521-9280.pdf
08-28-12, 03:03 PM
#26
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similar problem each time oil changed
I am also experiencing a similar problem with my 2007 LS460 L. The hesitation problem continues few days each time I have an oil change then disappears by itself. I was thinking that the problem was related to the valve recall. The local dealer in UAE (Al Futtaim) refused to do the recall for my car as it was shipped from the US.
08-28-12, 03:42 PM
#27
Lexus Test Driver
what do they do when they perform an oil change??? i have done mines no problems no need to disconnect the battery for that. hope they fix it.
Last edited by Lextrician; 09-03-12 at 10:15 AM.
09-03-12, 09:08 AM
#28
There is a lot of bad or misleading information being thrown around here. First of all, I read the pdf file posted above....that complaint does not seem to match what glenneagle and the others were complaining about.
I almost wish TSB's were not available on forums ONLY BECAUSE Lexus is never clear on tsb's on what the root cause of the problem is.........and the wording of the bulletins can be confusing to even experienced techs. I can promise you that most service writers don't really know what they mean and from there the bad information gets worse and spreads everywhere.
I will try to clear up a few things.
The first tsb, regarding hesitation from a stop......do you guys actually know what that software update changes???????? Most LS460 owners do not realize that after being stopped for a few seconds in Drive, the transmission actually shifts into neutral to safe fuel. Upon release of the brake pedal, it shifts back into first gear. Some people were quicker than the trans when going from brake to gas and you could feel it shift into gear right after pressing the gas. the TSB updates the software to make the transmission shift back into gear quicker, so even if you're quick from brake to gas, it will be in gear.
The 2nd TSB is very confusing. It deals with an overall lack of power from the engine caused mainly by ignition timing retardation. Many things can cause this, and the most likely is bad gas. certainly this is not always the case, but that's why dealerships default to that first.
The TSB is worded as though there is only one fix involving a software reflash and cylinder head replacement. this is not the case. the software reflash is supposed to be done first and there are separate "op codes" for doing the reflash only. I have yet to see one come back after the reflash but i'm sure there are some very very remote cases that actually needed engine work.
The second part, the engine work, is to replace the heads. From what I understand, the valve stems can have to much clearance in the valve guides and this can create a knock-like frequency that the knock sensors mistake for detonation. Therefore, the ignition timing is retarded. Ignition timing has a learned value called "knock correct learn". this is what dealerships will look at to see if the lack of power is due to ignition timing. If someone is running premium (which you should be!), the knock correct learn value should be around 22-25. on regular, this number may be as low as 16(and it will surge a bit too.). if it drops below 12...something else is going on. Usually bad gas or water in the gas. But THEORETICALLY it could be the valve guide issue.
I've only seen the heads replaced one time. This happened because the customer had a copy of the TSB and called Lexus and demanded that the engine work be done. He never even had the engine reflash done which probably would have taken care of it. Lexus caved and replaced the heads to make him happy, but if this were me I WOULD NOT HAVE THE ENGINE WORK DONE UNLESS LEXUS WAS COMPLETELY CERTAIN IT WAS NEEDED. that's a very big job...........and certainly the techs are qualified to do it.. but would you have open heart surgery based on an unlikely guess???? sure the doctor is qualified, but wouldn't you rather just leave it alone if it's not needed???
the original guy, glenneagle, sounds like he may have had one of the actual head problems. I say it sounds like it because I wasn't there and don't know the real deal. I don't know who the tech was and what he may or may have not done correctly. I hope his issue is now resolved. But please......don't read about his situation and assume that your car needs engine work also. Like i said, usually the engine software update takes care of this. Just make sure they do the correct update, not the one meant for the trans going from neutral to drive hesitation.
Lastly, the phantom oil change problem. I've heard of people complaining of this but how could an oil change cause this? it's just an oil change. nothing fancy. nothing is reset (besides MAINT light which has no connection to the Engine computer.) I bet there are a lot of people imagining it, and have an alternative suggestion for those who aren't.. It may not be the oil change, might be the test drive. The LS460 has a 380 hp engine. However, most people rarely use more than 100 hp of that. If that. No need to throw out guesses on the details, but when you take a car that has been driven by a feather-foot.........and finally give it the throttle it was designed to handle, all sorts of things happen. I can tell you I've been in many 460's that I've given only about 70% throttle accelerating to 65mph......and after just that one medium-hard acceleration run, you can see a cloud of smoke from the exhaust and you will have an awful sulfur smell coming from the car. Engines need to be run hard occasionally. that goes for any engine from any manufacturer. If you rarely exceed 20 percent of the engine's capability, you'll have a dirty and unhappy engine. THIS LAST PARAGRAPH IS SIMPLY A SUGGESTION. I HAVE NO EVIDENCE TO BACK UP THE THEORY.
I almost wish TSB's were not available on forums ONLY BECAUSE Lexus is never clear on tsb's on what the root cause of the problem is.........and the wording of the bulletins can be confusing to even experienced techs. I can promise you that most service writers don't really know what they mean and from there the bad information gets worse and spreads everywhere.
I will try to clear up a few things.
The first tsb, regarding hesitation from a stop......do you guys actually know what that software update changes???????? Most LS460 owners do not realize that after being stopped for a few seconds in Drive, the transmission actually shifts into neutral to safe fuel. Upon release of the brake pedal, it shifts back into first gear. Some people were quicker than the trans when going from brake to gas and you could feel it shift into gear right after pressing the gas. the TSB updates the software to make the transmission shift back into gear quicker, so even if you're quick from brake to gas, it will be in gear.
The 2nd TSB is very confusing. It deals with an overall lack of power from the engine caused mainly by ignition timing retardation. Many things can cause this, and the most likely is bad gas. certainly this is not always the case, but that's why dealerships default to that first.
The TSB is worded as though there is only one fix involving a software reflash and cylinder head replacement. this is not the case. the software reflash is supposed to be done first and there are separate "op codes" for doing the reflash only. I have yet to see one come back after the reflash but i'm sure there are some very very remote cases that actually needed engine work.
The second part, the engine work, is to replace the heads. From what I understand, the valve stems can have to much clearance in the valve guides and this can create a knock-like frequency that the knock sensors mistake for detonation. Therefore, the ignition timing is retarded. Ignition timing has a learned value called "knock correct learn". this is what dealerships will look at to see if the lack of power is due to ignition timing. If someone is running premium (which you should be!), the knock correct learn value should be around 22-25. on regular, this number may be as low as 16(and it will surge a bit too.). if it drops below 12...something else is going on. Usually bad gas or water in the gas. But THEORETICALLY it could be the valve guide issue.
I've only seen the heads replaced one time. This happened because the customer had a copy of the TSB and called Lexus and demanded that the engine work be done. He never even had the engine reflash done which probably would have taken care of it. Lexus caved and replaced the heads to make him happy, but if this were me I WOULD NOT HAVE THE ENGINE WORK DONE UNLESS LEXUS WAS COMPLETELY CERTAIN IT WAS NEEDED. that's a very big job...........and certainly the techs are qualified to do it.. but would you have open heart surgery based on an unlikely guess???? sure the doctor is qualified, but wouldn't you rather just leave it alone if it's not needed???
the original guy, glenneagle, sounds like he may have had one of the actual head problems. I say it sounds like it because I wasn't there and don't know the real deal. I don't know who the tech was and what he may or may have not done correctly. I hope his issue is now resolved. But please......don't read about his situation and assume that your car needs engine work also. Like i said, usually the engine software update takes care of this. Just make sure they do the correct update, not the one meant for the trans going from neutral to drive hesitation.
Lastly, the phantom oil change problem. I've heard of people complaining of this but how could an oil change cause this? it's just an oil change. nothing fancy. nothing is reset (besides MAINT light which has no connection to the Engine computer.) I bet there are a lot of people imagining it, and have an alternative suggestion for those who aren't.. It may not be the oil change, might be the test drive. The LS460 has a 380 hp engine. However, most people rarely use more than 100 hp of that. If that. No need to throw out guesses on the details, but when you take a car that has been driven by a feather-foot.........and finally give it the throttle it was designed to handle, all sorts of things happen. I can tell you I've been in many 460's that I've given only about 70% throttle accelerating to 65mph......and after just that one medium-hard acceleration run, you can see a cloud of smoke from the exhaust and you will have an awful sulfur smell coming from the car. Engines need to be run hard occasionally. that goes for any engine from any manufacturer. If you rarely exceed 20 percent of the engine's capability, you'll have a dirty and unhappy engine. THIS LAST PARAGRAPH IS SIMPLY A SUGGESTION. I HAVE NO EVIDENCE TO BACK UP THE THEORY.
09-03-12, 09:18 AM
#29
Are you employed by Lexus or a Lexus dealer, or are you an agent for either?