IS250 Starts up and then immediately stalls

[rob250]

Hi guys

 

Yesterday whilst driving on the motorway my IS250 lost power. The engine kept running but I could not accelerate even when the pedal was pressed down.

 

I managed to pull over and turn the car off and then back on and it was fine to drive home.

 

This morning I've come to start the car and it starts but then immediately stalls. I've included a video.

 

Spoke to my local garage and they have refused to get involved saying that Lexus are very hard to diagnose!

 

Any idea what is going on?

 

2011 Lexus IS250 Advanced, 45,000 miles. Full Lexus service and history.

[steve2006]

I found this which suggests a fuelling problem which I would agree with, also mentions a recall for the fuel sensor as a known failure.

https://www.my.is/threads/2009-is350-starts-runs-dies.611624/

I would also find yourself a not so local garage who are competent on Lexus.

[GMB]

Plug a diagnostic tester in the ECU and the results should tell you immediately what the most likely fault is.  Most common prices for the test are between £50 and £100 depending on the depth of analysis/faults found and the garage.

[rob250]

6 minutes ago, steve2006 said:

I found this which suggests a fuelling problem which I would agree with, also mentions a recall for the fuel sensor as a known failure.

https://www.my.is/threads/2009-is350-starts-runs-dies.611624/

I would also find yourself a not so local garage who are competent on Lexus.

Hi Steve,

I just checked the VIN against recalls and no outstanding recalls.  According to Lexus the fuel sensor recall was only on 2007-2009 and mine is a 2011.

Any recommendations for a good independent lexus specialist in cheshire/north west? 

[rob250]

6 minutes ago, GMB said:

Plug a diagnostic tester in the ECU and the results should tell you immediately what the most likely fault is.  Most common prices for the test are between £50 and £100 depending on the depth of analysis/faults found and the garage.

Hi GMB,

My local garage plugged in car to diagnostic tester and said no fault codes are coming back.

[GMB]

5 minutes ago, rob250 said:

My local garage plugged in car to diagnostic tester and said no fault codes are coming back.

That's a weird one isn't it.  It should throw an error if it isn't running right, so it's the old chestnut, intermittent faults that even Sherlock Holmes would struggle with. But I agree with Steve, it sounds like a fueling issue. Trouble with doing your own fault finding is finding the right bits in the plumbing rat's nest.   I know it sounds daft but sometimes it is better that the car stops altogether then at least you get a better chance at tracking the issue.   Very best of luck - fingers crossed🤞

[GMB]

 

If it's any help, I found this on t'internet...........................

 

 

However, these are just some of the most common causes and there are actually a few more. Here is a more detailed list of the most common reasons why your car starts then dies:

1. Lack of Fuel

The most common reason why your car starts then dies is because of a lack of fuel in the engine. This often happens because there is a small amount of fuel in the fuel rail – which is enough to help the engine start – but there is no fuel pressure to keep the engine alive.

Lack of fuel is pretty easy to locate, though. Either you can connect a fuel pressure gauge on the fuel rail, or you can loosen a bolt there carefully when you crank the engine to see if you have any fuel pressure. Be careful that you do not set anything on fire, though.

If you realize your car has low fuel pressure, you can check out our other article about Low Fuel pressure.

2. Anti-Theft Alarm System

The second most common cause is any problem with the immobilizer or anti-theft alarm system. When the anti-theft system is activated, the car will not send any power to the fuel pump, which builds fuel pressure in the fuel rail. This will cause the car to start for some seconds, as we talked about before.

If the anti-theft alarm system is from the factory, you should have a key symbol on your dashboard that should turn off a couple of seconds after turning the ignition. If it is not, try to lock and unlock your car and try again. If it is still illuminated, there might be a problem with your car key.

If you have an aftermarket anti-theft alarm, there might actually be a problem with the alarm itself or a bad remote. You may need to program the immobilizer hardware.

3. Dirty Fuel Filter

If the car stops after turning on the ignition, the problem could be a lack of fuel, as we talked about before. A fuel filter is a widespread cause of low fuel pressure.

The fuel filter is a filter that you should replace after a schedule – the precise time interval depends on your car model. If you haven’t replaced it for a long time, it might actually be clogged.

Fuel filters are often quite easy to replace and not very costly. If you have low fuel pressure, it can be worth trying to replace it.

4. Bad Idle Control Valve

The idle control valve‘s function is to keep your car’s idle steady. Newer cars control the idle with the throttle body, but if you have an older car with a steel wire to the throttle body, you have an idle control valve.

Often this idle control valve can become dirty, and this will stop the idle control valve from working properly. You can try to clean this valve to see if it gets better. Otherwise, you have to replace it or repair the wirings to it.

5. Vacuum Leak

The throttle body or idle control valve controls the idle by regulating the amount of air entering the intake manifold. If you have a major vacuum leak, this can actually cause the car’s air-fuel mixture to become too lean and your car will die after a couple of seconds every time you try to start your car.

Vacuum leaks are often quite easy to locate, either using an EVAP smoke machine or just listening for the leak, as it will often cause a high-pitched sound.

6. Faulty Spark Plugs

The combustion engine works by igniting an air-fuel mixture. The spark plugs provide the spark for this ignition. The pistons move up and down, which leads to movements in the crankshaft and the wheel axles.

If the spark plugs are faulty, the ignition will fail, and the car will stop moving. The car will start for some seconds, but misfire too much with a weak spark, causing the engine to die very soon after you start your car.

7. Fuel Injector

The fuel is injected under high pressure into the combustion chamber with the help of the fuel injectors. The fuel injectors’ job is to regulate, so the exact amount of fuel needed will enter the combustion chamber.

If a fuel injector fails, it can cause the engine to run on fewer cylinders and also cause the fuel pressure to become low if one is stuck open.

You can try to feel the fuel injectors with your hand while cranking to see if they click. If they are not making any clicking sound, one of them might be faulty, and you will need to test the fuel injectors.

8. Faulty Ignition Switch

If your ignition switch is damaged, you may start the car normally, and after a few seconds, the car will come to a complete stop. If your ignition switch is defective, you must check the switch contacts for wear.

The ignition switch is located behind the car’s ignition lock. In newer cars, it is most often impossible to replace the ignition switch itself; you have to replace the whole ignition lock.

9. Faulty EGR Valve

The EGR valve controls the exhausts that should be recirculated into the engine. If the EGR valve is stuck open, it may enter too much air into the intake manifold.

This can cause the mixture to get too lean, which will also, in turn, cause the car to start and then die after a couple of seconds.

10. Engine Control Unit (ECU)

The ECU is a computer system that controls various engine functions, including the fuel injection system. Since a vehicle needs fuel to move, any ECU malfunction will cause the vehicle to come to a halt after starting.

The ECU controls the engine components via a series of sensors. Over time, the sensors become faulty and pass on erroneous information to the ECU. In this case, you must take your car to a car repair shop.

What to do when your car starts then dies?

If your car starts and then dies immediately, the first thing you should check is if the immobilizer recognizes your car key. Check for the key symbol on your dashboard and make sure it disappears after a few seconds after you turn the ignition. After this, you need to check the fuel pressure. If the fuel pressure is low, you need to inspect the fuel filter and fuel pump.

[rob250]

6 minutes ago, GMB said:

That's a weird one isn't it.  It should throw an error if it isn't running right, so it's the old chestnut, intermittent faults that even Sherlock Holmes would struggle with. But I agree with Steve, it sounds like a fueling issue. Trouble with doing your own fault finding is finding the right bits in the plumbing rat's nest.   I know it sounds daft but sometimes it is better that the car stops altogether then at least you get a better chance at tracking the issue.   Very best of luck - fingers crossed🤞

Yep very strange. Even when the car dies and starts back up there are no warning/engine lights on the dash. 
 

I will take it to a good lexus independent. Anyone know a good one in the north west? 

[GMB]

Sorry I don't know any but would be interested to find one.  I have only ever heard or experienced good reports about Lexus Preston and Bolton but they do like to charge a lot for their services.

[Linas.P]

47 minutes ago, rob250 said:

I will take it to a good lexus independent. Anyone know a good one in the north west? 

Does not exist... 

If your Lexus has complex fault you are basically on your own, or you pay £195/hour in the dealer. 

Your fault does sound like fuel related, so I would start from checking fuel pump, there are also "bush mechanic" trick of just putting few drops of fuel or carb cleaner in each cylinder and checking if that makes it running for a bit longer (basically confirming it is fuel delivery issue).

I had same issue when my immobiliser died, starts and few seconds later stalls, but then you would get immobiliser code.

Generally speaking - no codes seems weird. Could be fuel pressure sensor - it is known to completely crash ECU, because it shorts 5V line, but that usually results in "crank - no start" condition, "start/stall" is more likely pump or immobiliser. Also could be injector driver issue, but again that would be "crank - no start".

BUT... loosing power when driving driving is unlikely to be immobiliser, as far as immobiliser is concerned, if engine started and it is running, it won't bother you until you need to start the car again. You can literally start car with key, leave it at home, drive across the country and only realise you have no key to start it again (it does say on the dash "key is not detected", but if you miss that you can drive for a while).

In conclusion, my speculation would still be fuel pump. Injector driver, fuel pressure sensor and immobiliser would have slightly different symptoms, but they all should be checked just to make sure.

Few relevant threads:

 

[GMB]

Fair comment Linas - Good advice. I especially like the spray a bit of fuel mix directly into the air intake/ throttle body, not as easy nowadays with all the complicated intake plastics. But it does help greatly with diagnosis to see if it is fuel starvation.🫡

[steve2006]

I found this one with a google search but no idea just how good or bad they are with diagnostics.

https://chesterautoservices.co.uk/car-service-prices/lexus/

Also found this video explaining how to disconnect the fuel pressure sensor and others at the ECU and then see if the car starts. From there it also explains how to disconnect the fuel pressure sensor alone and then see if it starts again. This is something you could initially DIY at zero cost to assist correct diagnosis.

 

[Linas.P]

3 spark plugs can be accessed on one side, not ideal as only 3 cylinders will fire, but as "bush mechanic diagnostics" it works. Engine obviously will stall, but if it runs for few more second then it is kind of confirmed it is fuel issue.

On other hand it may be redundant, as it is already clear that it is fuel issue, it is just not clear what is causing it. Because if it would be issue with spark, then the engine would not start at all.

[Linas.P]

4 minutes ago, steve2006 said:

I found this one with a google search but no idea just how good or bad they are with diagnostics.

https://chesterautoservices.co.uk/car-service-prices/lexus/

Also found this video explaining how to disconnect the fuel pressure sensor and others at the ECU and then see if the car starts. From there it also explains how to disconnect the fuel pressure sensor alone and then see if it starts again. This is something you could initially DIY at zero cost to assist correct diagnosis.

 

Yes that is the common - fuel pressure sensor issue. And it absolutelly do work as explained in the video. As mentioned stupid design means that faulty fuel pressure sensor causes ECU Communication to drop (can even blow ECU completely).

In theory, it should only trigger limp mode, but depending on the fault mode it could completely short ECU. 

[rob250]

Just a quick update for everyone.

Had another mechanic look over it today and was told that there was small deposits built up on each side of the throttle body flap causing it to stick.

They cleaned the throttle body and checked MAF sensor and all now seems to be ok!

Engine starts and runs fine now.

[BC99]

Only just seen this.

It's handy to have your own Bluetooth obd thing they're pretty cheap, and very handy. I think the free version of the Torque app allows you to view error codes, and clear them.

I would have suggested disconnect Battery for as long as possible, turn lights on to ensure all charge gone, then reconnect.

Sadly not all faults show up with obd. Things like a sticking throttle body as you possibly had, or similar mechanical rather than out of range sensor faults which makes things more difficult.