AZ1Smith

For the second time in about six months my 2006 LX 470 has stalled in 100 degree "plus" heat while stopped at an intersection after an hour or two of in town driving. My vehicle is used to seeing these temperatures. After the first occurrence the Lexus dealer had it for a week and could not duplicate it, nor give me an idea what the problem might be. An independent mechanic I talked to said it could be vapor lock caused by using "non" name brand gasoline. Since then I've been using Chevron and it did not stall again, until today. Any ideas?

RobRed

Vapor lock in a fuel injected LX? Not likely.

Describe stalled? Does it restart easily? Do you have to tow it?

AZ1Smith

In both cases the engine died when starting press the gas pedal to accelerate from an idle. Also, in both cases, the engine would not restart after trying for several minutes. In the first, case we had the vehicle towed to the dealer , and the dealer had no trouble starting it. In the second case, the engine restarted after letting it sit for about ten minutes.

RobRed

Is the check engine light coming on when this happens? If so there is an associated trouble code.

Taking a stab... There is an evaporative canister that scrubs fuel vapor that may be causing a pressure problem. If it stalls again remove the gas cap and see if it restarts. These evap canisters and the associated plumbing do go bad.

AZ1Smith

Thanks for the input. The check engine light does not come on, and the dealer says there are no trouble codes. We have the vehicle in at the dealer again, and once again, they are not able to duplicate the problem. Frustrating!

LX470570

MAy sound dumb... any chance of a bad gas cap?

SC400slide

iTrader: (11)

Your thermostat. Does the LX470 have a safety feature so when the engine get's to hot, it will shut down and won't let anything happen until it's cooled down? Maybe I'm skipping ahead to 2020!

kklaus121

Hello AZ1Smith,
I have the exact problem as you do with my 2006 LX 470.
One mechanic thought it could be the fuel pump so I had that replaced and that helps with the problem but does not solve it.
I have replaced the fuel cap
I have had the dealership perform and EVAP check that checks the entire evaporative emission system and no problem found.

On hot days if I drive for about 45 minutes, then turn the engine off and let it hot soak for 20 minutes or so, then drive for another 30 minutes or so the engine will be very hard to start and may take cooling off for anywhere between 10 and 30 minutes.

Question: did you notice a strong alcohol/fuel smell when this happens to you? For me I get this smell every time the hard start occurs.

V8_Fan

I had this problem in AZ on my old 4runner. I suspect the mass air sensor (that squarish thing on top of the air filter) was dirty or too old. The 3rd gen toyota 4runners used a wire in the MAF whereby people who had those oiled filters like K&N had issues since the oil would gum up the wire and MAF. I don't think the ones on the LX470's are like that. This usually causes on initial cold start up, though, so I don't think it's your problem. It sounds like a fuel problem (fuel not getting into the cylinders). Do you smell a gas smell? Are the cylinders just flooding and maybe it's not igniting?

kklaus121

I don't think this is a MAF issue because that would normally throw a code.

I definitely believe it is a fuel problem. It may be the fuel pressure regulator. I am going to try to rig up a mechanical fuel pressure gauge this week and see what is going on with fuel pressure.

When it is hot I do have a fuel vapor smell, but not from the engine compartment or exhaust. It is coming from underneath the vehicle and is likely near the charcoal canister or the fuel filler tube. I suspect some type of issue with the EVAP system when it is hot and running ethanol fuel.

AZ1Smith

Yes, there was a strong fuel/alcohol type smell after each occurrence. Is the evaporative cannister expensive to replace?

kklaus121

The vapor canister is indeed expensive. List price is ~$850 and I can put you in touch with an individual that can get you one for ~$640 if you determine this is your problem. Should be a DIY job if you are a bit handy. It is located above the spare tire so if you drop the spare you will have access to all the connections.

You and I should stay in touch on this issue because if one of us can solve it then likely we can help the other one out.

I will hopefully have the parts this week to install the fuel pressure gauge on the rail. I'm hoping this will give me some clues. I will update this thread as I get information.

kklaus121

I have finally gotten the fuel pressure gauge installed. It is running at 42psi under normal driving conditions and bumps to 44psi when I get on it. Certainly this is in the specified operating range of 38-44psi. I have attached two pictures. I will keep updating this thread as I get more information, but it may be June before I get more information as winter is coming to CO.

RobRed

The land cruiser version can be had all day long for $425 via TPZ and TPE online.

kklaus121

RobRed,
that is certainly a better price than I have found on a new one. I'm not familiar with TPZ and TPE and a quick google search didn't seem to produce any relevant hits. Can you provide more detail on these sites? I'm fairly new to the Toyota world.