drogersthx

Friday I had my 40,000 mile service done on my 2007 LS460 at the local Lexus dealer. As soon as I picked it up I had an acceleration problem (which I have had intermittently before), but this time it was very bad. It felt like an old carbureted car bogging down.

Saturday I was driving and had been on the road for about 20 minutes, stopped for a sandwich and then upon leaving the parking lot and entering the road the car bogged again, but this time it stalled. I looked down at the tach and saw it was at zero and there was a message on the dash that said something to the effect of “VSC Problem. Have dealership check car.” I tried to restart the car but to no avail so I coasted to a stop, still in the road.

I turned the ignition off and tried again to restart the car. It cranked and cranked but would not start. After 2 or 3 tries a new message appeared “Low Battery. Please start the car.” At this point the starter would not even turn over the engine and it only clicked (I had not heard that sound in several years). At one point a message appeared on the NAV screen that said "system restarting, do not power off", but aftre it was finished the car would not start. So there I was stranded in the middle of the road.

I have owned 2 LS400s, one LS430 and now I drive this LS460. I have been a loyal LS owner since 1995. The one thing I did not like about this car when I got it was the fact that the parking brake was electronic and not mechanical. I have wondered that if in a situation I really needed the parking brake for an emergency and the battery was dead would it do anything?

But if what happened to me Saturday was by design, I cannot fathom how stupid of a design that is. The car clearly had enough battery left to keep the engine running. Whatever happened that caused the VSC message to appear could not have been so catastrophic that it needed to immediately and without any warning stop the engine from running. I am grateful that I was not on some highway under construction without any shoulder and was only on a thoroughfare that had three lanes in my direction.

Has anyone got any idea what may be going on here?

jmcraney

WOW! Bummer!!

The possibilities are numerous and a guess is about all I can come up with.

I would suspect that the fuel flow was interrupted and the engine died as a result of that. All those other things were a result of the engine quitting.

Reasons for a fuel problem might be: empty tank; water in the fuel; diesel in the fuel; improperly installed fuel filter; fuel pump failure; etc.

It would be neigh on to impossible to provide a warning about impending fuel flow interruption.

The VSC warning probably came on as a result of the engine stopping.

The "Low Battery" was probably a result of the battery being depleted by your prolonged attempts to start your car. If you used the "49 Ford Technique" to try to start your car then that would deplete the battery in short order. These cars use a lot of energy in starting and you can use most of the available energy in just a few minutes of cranking. Although it is tempting to grind on the starter, I think it is wise to give up trying to start the car after two or three attempts of a few seconds each. These engines are computer controlled and they will start, if they are going to start, in a few seconds.

The "System Restarting" is the normal message that you get when the battery is disconnected and reconnected. That probably resulted from the battery voltage dropping very low as a result of your prolonged and numerous starting attempts. Batteries get very hot when they deliver a lot of energy in a short time and as a result they get hot and the voltage drops. After they cool off the voltage comes back up and sort of gives the effect of disconnecting the battery.

As for your concerns about the parking brake design: I expect that the parking brake is designed to use very little energy and to operate over a wide range of battery voltages including very low voltage that might occur when a battery is depleted.

Please tell us the rest of the story.

drogersthx

Thanks for your thoughts jmcraney.

The fuel tank was about ¾ full and I have no reason to believe there were any impurities in the fuel. I was only able to try to start it 2 or 3 times before it would not turn over the starter anymore so the battery had to be close to the edge before the incident. The frustrating part is that supposedly the battery had been load tested by the dealer the day before as part of the 40,000 mile service.

For future reference, if you have any other methods to try other than the “49 Ford Technique” I am all ears

edarte

Have you had the valve spring fix done?

bsims_01

Though the engine in my 2007 LS never stalled as it did with yours, I experienced the same acceleration problems you describe. It only happened on occasion until I had the VSR done last December. After the recall was performed, the car frequently lost power - - very similar to the "bogging down" you are experiencing. This happened several times in heavy traffic and created a very dangerous situation.

I took the car back to the dealership and was informed that the cylinder heads needed to be replaced. According to the service adviser, some of the early production models had a problem with the valves not seating properly in the heads. Sometimes under acceleration, this would cause the knock sensor to detect a problem and retard the timing to prevent major engine damage. Hence the "bogging down".

Anyway, the engine has performed flawlessly since the heads were replaced. Good luck and hope this helps.

JFNash

First off glad you're safe and the car didn't stall in the wrong place.

Do you know if the dealer ever replaced the fuel pipes?

I remember reading they need to be replaced on all 2007 LS460's due to a design flaw.

I agree with jmcraney on his assessment. I think if it was an engine problem, the "check engine" sign would have probably been lit. The VSC warning message is a common sign of so many issues, including a dying battery. I wouldn't worry about it. So no worries.

The system restarting message on the nav screen will appear anytime the battery is depleted then recharged or disconnected then connected. Also no worries.

Start the troubleshooting with the fuel system (pipes, pump, ...etc).

Good luck.

drogersthx

Yes the valve spring fix has been done. I have had acceleration hesitation problems both before and after that fix.

I do not know if the fuel pipes have been replaced – they were not since I have owned the car (I am the second owner).

So here is the rest of the story (so far).

The car was towed to the dealership where it sat over the weekend.

When they got to it the first thing they discovered was that the battery was dead (big surprise) so they replaced it. After they replaced it, they reported that they could find no other problems, had test driven it and it was fine. I did not respond to that voice mail at first and then a few hours later I got another call and they said that upon further test driving the tech had experienced the bogging/hesitation problem.

So they reflashed the ECM and now it really seemed ok. I asked if they had checked the spark plugs to see if the heads needed to be replaced and was informed that the first thing they do is reflash the ECM and then if I have problems again they consider whether to replace the heads.

I requested an audience with a manager and when I arrived at the dealership was able to meet with one of the service managers as well as someone who appeared to be a senior technician. They both were quite pleasant and listened to my concerns, which primarily revolved around the fact that IMO the car should never just stall. I asked about what the log had shown with the error messages and was informed that there was no log because it went away when the battery died.

In the end, they convinced me that the stalling issue could be reasonably explained by a suddenly dead battery causing the car’s myriad of computers to be inoperative due to low voltage and it just shut down. Very bad timing for me and for them, but just bad timing nonetheless because they assured me the battery had been load tested just the day before.

They comped the new battery, which I am sure was not covered under warranty, without me even asking, so all in all they did a very good job of handling the situation.

When I got back in the car to drive it home, it was a hot rod once again. I will keep my fingers crossed that this will be the end of these issues, but it gives me pause to seriously consider buying an extended warranty when the CPO warranty expires.

caha14

Happy ending to the story at this point... Good to see!

This TSIB may be of interest. The ECM reflash is included here (I had it done on my '08), and VIN cutoffs are provided for when the cylinder head change may be applicable. Falling in the VIN range doesn't guarantee that you will need the new heads, but at least you will know where your car falls in the range.

http://www.lambros.net/LexusTechInfo...SB-0033-08.pdf

Mikey100

Good story.

Informative as well.

Thanks for sharing and continued Good Luck to you.

Mikey
Lake Oconee, GA