Car stalls when tank is mid to full ???
#31
04-05-2012, 02:45 PM
Sorry but I think you might be confused here. I try and explain the best that I can.
The purge line in the tank and the purge valve, all work together in a system to purge fuel vapors from the tank. If the hose inside the tank tears/breaks, then when the system does its purge cycle, it sucks fuel into the engine. Depending on how bad the tear/break is it could be a lot for fuel of just a little. When the fuel reachs the engine it is considered unmetered fuel, just like when you have a vaccum leak it would be unmetered air, but with fuel. The fuel did not come in from the fuel rail which the ecm monitors as it goes into the engine. Then the o2 sensors read the rich or unmetered fuel causing the ecm to try to correct for the probelm and thats when the stumble happens. The ecm will try and lean the system out or remove fuel to correct the issue. The reason it happens at a full tank to half is that the line connects to a hard line at the top of the tank. So has the fuel splashs around it gets inside the line. This system is more of an emissions system.
The fuel pump will always drive to keep the fuel pressue in the rail as requested by the ecm. Nothing in the emission system has control over that. The only thing the emission system cares about is the fuel level in the tank. So that it may check for leaks, or fuel vapor leak.
You would only ever get a engine light if the tear/break of the purge hose is bad enough. Which the ecm will catch because it has tried to correct to the unmetered fuel in the engine, but can not correct the fuel trim anymore, without causing catalyst or engine damage. That is when codes like stuck o2 sensors or catalyst codes come up.
The purge line in the tank and the purge valve, all work together in a system to purge fuel vapors from the tank. If the hose inside the tank tears/breaks, then when the system does its purge cycle, it sucks fuel into the engine. Depending on how bad the tear/break is it could be a lot for fuel of just a little. When the fuel reachs the engine it is considered unmetered fuel, just like when you have a vaccum leak it would be unmetered air, but with fuel. The fuel did not come in from the fuel rail which the ecm monitors as it goes into the engine. Then the o2 sensors read the rich or unmetered fuel causing the ecm to try to correct for the probelm and thats when the stumble happens. The ecm will try and lean the system out or remove fuel to correct the issue. The reason it happens at a full tank to half is that the line connects to a hard line at the top of the tank. So has the fuel splashs around it gets inside the line. This system is more of an emissions system.
The fuel pump will always drive to keep the fuel pressue in the rail as requested by the ecm. Nothing in the emission system has control over that. The only thing the emission system cares about is the fuel level in the tank. So that it may check for leaks, or fuel vapor leak.
You would only ever get a engine light if the tear/break of the purge hose is bad enough. Which the ecm will catch because it has tried to correct to the unmetered fuel in the engine, but can not correct the fuel trim anymore, without causing catalyst or engine damage. That is when codes like stuck o2 sensors or catalyst codes come up.
. You are really helpful to all of us, so we don't go to the dealer totally ignorant, and actually have a conversation on what the problem might be. Much appreciated..
#33
04-15-2012, 12:14 PM
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The line is a small rubber hose almost touching the top of the tank, if you don't reach in far enough to the passenger side of the tank, no way you will see it..even with a mirror you can have trouble
#34
04-16-2012, 12:17 PM
Irish07, I am too going to address this problem with my technician next week. If telum01 and his mechanic saw nothing, what does my mechanic have to look for? Something in particular? My car has the steering at the left. Also, if this a hose line that runs at the top of the fuel tank and then it attaches to a hard line, it will be almost impossible for somebody to change the hose as the opening of the tank is very small. How can you work thru that small opening?
#36
04-16-2012, 12:26 PM
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Rep Power: 204 Irish07, I am too going to address this problem with my technician next week. If telum01 and his mechanic saw nothing, what does my mechanic have to look for? Something in particular? My car has the steering at the left. Also, if this a hose line that runs at the top of the fuel tank and then it attaches to a hard line, it will be almost impossible for somebody to change the hose as the opening of the tank is very small. How can you work thru that small opening?
Think Aston warranty pays something crazy low like 1 hour..and yes all is done though that top access hole
#37
04-16-2012, 12:27 PM
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Yep..doesn't matter LHD or RHD it's on the passenger side
#38
04-16-2012, 01:38 PM
Sorry, irish07. I thought you were in the UK.
So, do we should look for a disattached hose, cracked hose, or just change the hose altogether even if it looks OK? What is regularly the main reason for what you guys have done this for? Thank you.
#39
04-16-2012, 03:07 PM
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The hose gets gummy..it's about 1/4inch diameter and about 4-5 inch in length..when it gets this "gummy" state, you can stretch this 4-5inch hose about 20 inchs..it pretty much becomes tar
#40
04-16-2012, 10:28 PM
We could see the hose. The clamp was fine, the hose looked fine. He said the hose felt rather soft, not hard or cracked or torn. So if it gets too soft, that can cause the same problems as if it was cracked or torn?
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
#42
04-17-2012, 01:14 AM
We could see the hose. The clamp was fine, the hose looked fine. He said the hose felt rather soft, not hard or cracked or torn. So if it gets too soft, that can cause the same problems as if it was cracked or torn?
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
#43
04-17-2012, 10:13 AM
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Rep Power: 204 We could see the hose. The clamp was fine, the hose looked fine. He said the hose felt rather soft, not hard or cracked or torn. So if it gets too soft, that can cause the same problems as if it was cracked or torn?
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
I rarely have the stalling issue so my hose might be fine. I wanted to check it just in case there was something obvious.
The clamps don't come loose on there own, never had one yet..its the hose that faults. There can be a pin sized hole near the clamp or really anywhere on that litle hole..if fuel gets sucked through that pipe, you will almost have an instant stall.
A test you can do with the tank full, remove the purge line from the vapour valve(it's below the washer resevoir, access from under the car)..get a vaccuum pump on there and pump away..if you get fuel, you have proven there is a leak, get into the fuel tank and check where the leak is coming from, hose, clamps..etc
#44
04-17-2012, 08:43 PM
Do any of you guys know what's the part number of this hose? I would like to order it from an AM parts retailer and change it anyway. If we are going to see inside the tank and this is a recurrent incident with these cars, I might as well change it and see if the stalling stops, right?
Does anybody knows a reputable online AM parts distributor?
Does anybody knows a reputable online AM parts distributor?
#45
06-20-2012, 07:36 AM
Someone mentioned DIY...
Has anyone actually done this themselves and please tell me what I am getting myself into and what I will need to pick up from Discount Auto if I choose to take this on myself.
Has anyone actually done this themselves and please tell me what I am getting myself into and what I will need to pick up from Discount Auto if I choose to take this on myself.