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I have a 2006 IS 250 AWD with about 41K miles. I have only had the car serviced at the dealer and am

the original owner.

Yesterday, while driving home from work on the interstate the car suddenly lost power, stalled and wouldn't re-start.

I tried re-starting the vehicle three times; each time it was struggling to start and stay running. It felt like a spark plug

had failed.

Called Lexus RSA who sent AAA to meet me and try to help with the problem. Electricals were still working fine, so we ruled out an alternator. Car would still turn over, thus the starter was OK. Service guy did something very unusual.

He took a rubber mallet and smacked it against the fuel tank while I tried to start the vehicle. Car started right up and

I drove it the remaining 15 miles home. Next morning, car started right up and I took it to the dealer to see what may

be wrong.

The dealer is trying to diagnose the problem, and I hope to have an answer tomorrow.

Anyone else having this same problem?

Also, thanks for the heads up on the dusty brakes. Has been driving me crazy for two years now. Dealer is replacing the pads free of charge tomorrow while fixing the other problem.

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WOW!! Rubber mallet? I wonder what hitting the fuel tank fixed. Please keep us up to date. Just wondering, was the air conditioner running?

The rubber mallet thing really caught me off guard as well. I have hit a starter before with a hammer, but a mallet on a fuel tank?...

I did talk to a friend of mine who does quite a bit of work on cars. He thought maybe the fuel pump bypass, which recircs gas back to the tank when the injectors aren't calling for any fuel, may have seized up and the mallet knocked it loose. Which makes a lot of sense.

I will let you all know what the dealer finds out later today. They were having trouble diagnosing the problem given the trouble codes that came out of the computer.

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All hail the 'rubber mallet' aka the computer hammer!!!! :)

The fuel pump bypass valve is actually located on the fuel rail in the engine compartment. So I would guess that it was a problem with the fuel pump itself or some sort of contamination. Was the fuel tank recently run down to a very low fuel level??? Just a guess.

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All hail the 'rubber mallet' aka the computer hammer!!!! :)

The fuel pump bypass valve is actually located on the fuel rail in the engine compartment. So I would guess that it was a problem with the fuel pump itself or some sort of contamination. Was the fuel tank recently run down to a very low fuel level??? Just a guess.

I have heard of fuel pumps going bad when you run the fuel tank empty or very low. I have heard that the cause is two things, one: cavitation of the pump (sucking air), and two: pump picking up sediment in the tank. I don't have direct experience with this, but that's what I've heard from auto-mechanic types.

Someone on another forum posted a arrangment of the fuel pump in the ISx50. Apprently it is impossible to cavitate the pump as it is located in its own well at the absolute bottom of the tank. The pump will turn off before is runs out of fuel to aviod overheating. The sediment one is still possible I figure.

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Starting in the Mk4 Supra they came up with a clever design where the fuel pump sat in it's own small reservoir... this avoids several common problems with fuel pumps-

1. The problem where with low fuel the pump isn't being properly cooled... since you'd now have to run it to pretty much bone dry to exhaust the fuel in there cooling the pump

2. The problem where the pump sucks air because the level is low, the tank is poorly designed, and when you floor it all the fuel sloshes to one end, away from the pump pickup.

The ISx50 uses this same design.

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I have heard of fuel pumps going bad when you run the fuel tank empty or very low. I have heard that the cause is two things, one: cavitation of the pump (sucking air), and two: pump picking up sediment in the tank. I don't have direct experience with this, but that's what I've heard from auto-mechanic types.

Yes, fuel injection does cause several problems if the tank runs dry or low. If an air bubble gets in the system it will cause a mere misfire or hiccup, though, not thecar to stall. You may have had sediment in the fuel pump, locking it up and restricting the right amount of fuel to the engine. I know that it is a VERY bad idea to fill up at the pump if there's a refill truck, as the truck dumping gas in the underground tank stirs up all the sediment - sand, dirt, pebbles, etc. - at the bottom. In other words, if you see a gas truck at the gas station, GO SOMEWHERE ELSE UNTIL THE NEXT DAY. Hope this all helps, keep us updated.

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I've also heard that fuel pumps need to stay wet or they can overheat.

I would hope that Lexus, in all it's automotive wisdom, would have designed the fuel pump to avoid damage should the fuel tank run empty. :( ........... but then again why is the paint so soft you have to wash and dry it with super special fabric material!! <_<

Responsible Lexus drivers don't run their tanks down to the fumes.

As for drying, I use the touchless car wash and then go for a 100 MPH (no drifting) run and it dries everything except the trunk lid and rear bumper. For that I use a waffle weave microfiber drying towel. In 2 1/2 years I haven't seen any evidence of soft paint and have no scratches, rock chips, or swirl marks. I think the Zaino CS helps in that department too.

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Responsible Lexus drivers don't run their tanks down to the fumes.

As for drying, I use the touchless car wash and then go for a 100 MPH (no drifting) run and it dries everything except the trunk lid and rear bumper. For that I use a waffle weave microfiber drying towel. In 2 1/2 years I haven't seen any evidence of soft paint and have no scratches, rock chips, or swirl marks. I think the Zaino CS helps in that department too.

Responsible drivers don't go 100MPH with wet tires and brakes either. :P

Gotch ya (kidding)

I can confirm that the ISx50 Obsidian paint is soft as I got two rock chips in the hood before the first 5k miles. I guess I should have had the clear bra installed upon delivery instead of during the first maintainance. I wonder if different colors have different material properties? My car is black so I use the Mr. Clean Autodry. No towel needed.

Thread has been offically hijacked.

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I picked up my car last night after the dealer spent 2 days trying to diagnose the problem.

They put the car through a series of diagnostic checks to see what the failure alarm was,

and if it would help diagnose the problem. The failure code was a "communication fault"

in the fuel system. They were not able to recreate the problem even after driving the

car around quite a bit and at this point are chalking it up to a freak occurence. Given that

no one else has seen the problem that I can find nor they can find, it may just be that.

The most likely scenario in my mind is sediment in the fuel tank locked open the bypass line,

or for some other reason it seized up, and starved the drive system of fuel. The rubber mallet

either dislodged the sediment, or loosended the bypass valve allowing it to function properly.

If either one of these is correct, it will return.

I do typically run my tank down to 1/4 full, where it was when the fault occurred. I drive 350-400

miles per week, and there are no gas stations within a five mile radius of my house to product

ground water.

If I learn more, I will re-post anything we find.

Just a heads up, if you do have the new brake pads put on, they are not nearly as "grabby" as

the originals.

Thanks to everyone that replied.

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  • 6 years later...

I have a 2006 Lexus IS250 and needed to be towed. The tow driver hit the gas tank several

times with a rubber mallet and soon as he let it off the truck I pressed the start button and started

right up and ran the engine for awhile. The next morning I tried to start it to no avail.

The tow driver said the gas tank has sediment in it that gets sucked into the fuel pump screen

and stops the flow of gas and the engine dies.

Geno

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Good info.

Should I carry a rubber mallet in trunk (just kidding) ?...

Certainly I don't wont to run the tank nearly empty, and I use only Chervron premium gasoline, so no problem so far.

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  • 2 weeks later...

Well, I found a shop that knew what the real problem was with my IS250. The ECM wasn't grounding properly

and caused the engine to stall. It was fixed and no problems now.

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