Hello,

My 2008 LR2 HSE has been having this strange problem. the past two times that I've filled up with gas (different gas stations) and didn't overfill I stopped filling when it clicked off.
Well when you go to start the car after the fill up it runs really rough like it's going to die and if you give it more gas the idle drops even more.
But if you shut the car off and start it up it starts and runs fine for my hour commute.

I was going to order a purge valve but then today when it was sitting over night it took 3 tries to even start the LR2. On the 3rd try it did start and run fine.

So now I'm confused I don't think a purge valve would flood the car when it's sitting overnight but I could be wrong I have never had one go bad before so I'm not to familiar with the symptoms.

Thanks for any help.

Oliver

 

There have been a couple issues with these symptoms, but all are software related. There is an issue with a hot start, after a short engine off period, which will not log a fault code, and there has also been an issue with a stumble on startup, but that will throw codes, not always turn on the MIL though.

I have attached both of these service bulletins.

You would have to have several other issues in order for the purge valve to cause this problem.

 

Thank you my vin does fall within the hot start issue range.
I'll have to schedule the service and see if that fixes it.

 

Hmm now I don't even trust it to drive. I was going to take it out today but the idle is all over the place. It's the strangest thing no check engine light and it's acting so strange all the time now.
Once the car warmed up it seemed to stabilize but I don't trust it driving to the dealer.
Here's what it's doing now at idle

http://home.comcast.net/~oliver1071/idle.wmv

 

Ok, sorry for my misunderstanding the issue at hand. Do not worry about the software update. It is one of two things, and the first would definitely turn on the MIL. Either the throttle body has a bad internal sensor, or you need to clean your throttle body. The is not that common of an issue on the LR2, but I have seen it before.... very common on the LR3 and RRS.

The only issue is that the throttle body is not very accessible on the LR2. It is fine to drive, once you're off idle it should run fine. The best way to do this on this engine, is to have an induction service preformed. Find a repair shop, most decent ones are able to do this. I have fully explained the induction service in other threads on this forum, and others. If you do a quick search you should find out exactly what it is that needs to be done, and pointers on the process. What happens is that carbon builds up at the throttle blade, and restricts air flow. The throttle is responsible for maintaining proper air flow at idle, and has a learned idle position. When the build up gets to the point that it creates an air dam, the throttle needs to be opened and closed in order to keep running, and you end up with exactly what you have in the video.

Any shop that has a BG sign outside of it should be able to do the induction service for you, including the dealership.

 

Thanks I'll search for the thread. You weren't mistaken this is just a new symptom. The original problem still exists I filled up the car again with gas and immediately upon restarting it the idle was really low almost stalling no surging though. Shut the car off and restart and it's fine again.

The only thing that has been done to the car two weeks ago the battery died out of nowhere while I was at work. Started fine in the morning then completely dead 8 hours later the doors didn't even unlock it was that dead I had to use the key.
I replaced the battery in the parking lot and then the next fill up with gas this all started happening.

The car has been running perfectly for years.
I'm just amazed that there is no check engine light with this erratic behavior.

Thanks again I'll have more time to go over the car this weekend.

 

When it is idling rough, does it act fine if you just give it a little bit of gas, in Neutral? Say raise it to 12-1500 RPM.

By replacing the battery, the throttle adaptions were reset. This caused the throttle to 'learn' a new closed position, which in turn has exaggerated the carbon build up issue. The check engine light isn't coming on, as it is doing what it is designed to do, it doesn't see this as a fault, it is commanding the throttle more open, and then closed, and the sensors are reading correctly. Eventually you should get a rich code (P0172/175) due to a lower amount of air being drawn in then expected, but it can take a while for that to trip a code.

 

Good and bad news. The throttle body cleaning helped the surging idle.
But I just filled up with gas today and has the same low idle almost stalling upon restart.
but when I shut the card off again and immediately turned it back on it was fine again.
I filled up about a 1/2 in to my trip and then drove another 1/2 hour with no problems after that.
I even restarted the car when I arrived at my destination to see if it was doing that when it's hot or only on fill up. It did not act up when I started it without filling up.
Oh and while it's in the low idle condition and I try to give it gas it drops even lower. I'll have to try pushing the throttle down hard to see if I can bring it up next time.
I also want to test filling it up with a couple gallons of gas so it's not completely full to see if it does it.

Thanks for any further sugestions.

 

Try simulating filling up with gas, and see if it still does the same thing.

Drive like normal, pull over somewhere, shut the engine off for a few minutes, get out of the car like you normally would while pumping gas, and then restart it. If it still messes up, get the software updated per the bulletin above.

 

Ok I did not get the results that I expected.
I drove home yesterday 1 hour 35 miles.
Shut off the car for 6 minutes then restarted everything was normal.
Then this morning I went to the closest gas station (couple blocks away) to top off and it also started fine.

I will drive it tomorrow to my normal gas station 15 miles 30 minutes and top it off again and see what my results are.

I could solve the problem by always going to the close gas station but that really wouldn't fix the problem.

And I have experienced this problem at other gas stations but I was already driving for a while with those as well so I assume it wouldn't be a problem at my particular gas station.