HELP - Fuel starvation problem
#1
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This first happened yesterday on a long Scoobymeet drive and was pretty scary!!
After having a new uprated Sard fuel pump fitted on Saturday morning I have been experiencing what appears to be fuel starvation.
The problem occurs when the tank is under two thirds full and happens immediately after coming off a bend or roundabout. As I straighten up and try to accelerate the power dies completely (almost as if the brakes have been slammed on). The lower the tank gets the longer it takes to regain power and this can be up to 10 seconds when the tank is only a quarter full!
With the standard fuel pump I had never experienced anything like this before even when the tank was almost empty. I filled up three times since the pump was fitted and experienced the same thing each time.
Any suggestions as to the cause of this and any recommendations to overcome it would be very welcome.
Thanks
Mikee
After having a new uprated Sard fuel pump fitted on Saturday morning I have been experiencing what appears to be fuel starvation.
The problem occurs when the tank is under two thirds full and happens immediately after coming off a bend or roundabout. As I straighten up and try to accelerate the power dies completely (almost as if the brakes have been slammed on). The lower the tank gets the longer it takes to regain power and this can be up to 10 seconds when the tank is only a quarter full!
With the standard fuel pump I had never experienced anything like this before even when the tank was almost empty. I filled up three times since the pump was fitted and experienced the same thing each time.
Any suggestions as to the cause of this and any recommendations to overcome it would be very welcome.
Thanks
Mikee
#3
Ecu Specialist
Sounds as though the pump has been installed with a different pick up pipe/filter which is not on the bottom of the tank, need to make sure that it is otherwise you have a lot of fuel sloshing around and the pump can't reach it. OEM filter/pickup is pretty large, most aftermarket ones are much smaller
#4
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yep your right bob, the filter wasnt swaped and the one on the new pump is alot smaller, will try swaping it over
thanks
mikee
thanks
mikee
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My car suffers since the Walbro pump went on on anything under 1/8 of a tank in a straight line. Need to take it out again and look at the pickup - it was a bit shorter in length from the top of the tank. On track happening on 60% full.
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#9
Ecu Specialist
Its alot shorter, I get surge accelerating in a straight line at 0.3 bar when the light is only just on, either I have a shed load of power (possible) but more likely the same thing, compared the old and the new just now, its a good 40/50 mm different.
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Moray - just attached a long hose direct to the pump and be done with it
How did John F. get on with his STi in-tank anti-surge pick-up thingy?
Richard
How did John F. get on with his STi in-tank anti-surge pick-up thingy?
Richard
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Will need to look again, but can't we move the rubber hose down a bit and use the original filter/sock thingie to get "deeper"?
I was sure there was a difference with the new pump, glad others find the same and it is not just me. Also fuel surge at 60% may be due to the higher pickup - previously it only surged on 30% or lower round the knockhill hairpin- both in the dry, both sliding so presumably similar g force? Will wait to empty this tank and then have a look.
I gather the STi pump is smaller physically than the UK one?
Sorry Richard cross posted with you - have you lengthened the hose and it works then?
[Edited by john banks - 8/6/2002 12:19:26 PM]
I was sure there was a difference with the new pump, glad others find the same and it is not just me. Also fuel surge at 60% may be due to the higher pickup - previously it only surged on 30% or lower round the knockhill hairpin- both in the dry, both sliding so presumably similar g force? Will wait to empty this tank and then have a look.
I gather the STi pump is smaller physically than the UK one?
Sorry Richard cross posted with you - have you lengthened the hose and it works then?
[Edited by john banks - 8/6/2002 12:19:26 PM]
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Whoops - didn't re-read my post. No I havn't lengthened the rubber hose connecting the pipe...this was a failed attempt at a joke regarding gas-station pump hoses :-)
It would be preferable to lengthen the hose because it's a tight fit anyway. Problem is the metal bracket that the feed end of the pump mounts into via the rubber bush.....you'd need to cut/lengthen this.
I actually thought about the length difference when installing the new pump, and stupidly disregarded trying to fit the OE collector 'cos I was in a rush In my defence it took much longer than expected due to all the fuel that p*ssed out after clamping the wrong hoses, lol!
Changing subject wildly - I did mine with a full tank & left the car to stand for an hour after my drive home before removing the pump. When I did it was still hot to the touch! How hot does the fuel get (again, I didn't stick my hand in the full tank to check (was this wise or stupid?!))? And has anyone tried any fuel cooling solutions?
Richard
It would be preferable to lengthen the hose because it's a tight fit anyway. Problem is the metal bracket that the feed end of the pump mounts into via the rubber bush.....you'd need to cut/lengthen this.
I actually thought about the length difference when installing the new pump, and stupidly disregarded trying to fit the OE collector 'cos I was in a rush In my defence it took much longer than expected due to all the fuel that p*ssed out after clamping the wrong hoses, lol!
Changing subject wildly - I did mine with a full tank & left the car to stand for an hour after my drive home before removing the pump. When I did it was still hot to the touch! How hot does the fuel get (again, I didn't stick my hand in the full tank to check (was this wise or stupid?!))? And has anyone tried any fuel cooling solutions?
Richard
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wrxrob, the original pumps may not go wrong (and are quieter with fewer pickup problems) but they do not maintain pressure on a heavily modified car. Even at supposedly standard fuel pressure, you can get more out of your injectors. I am running only 7-8% CO but it is quite easy to get the IDC to 94% even with the uprated pump. Since I could use less injector duty cycle with the new pump compared to the old, I would be unhappy relying on the standard pump.
#17
Ecu Specialist
The original pumps are a variable feast, some are nearly twice as large in diameter as others The filters are different depending on pump, some are angled compared with others. The one common thing is the diameter of the pickup point on the pump and so the original filers should fit however its a bit of a lottery as to wether the original filter on the new pump will actually be in the right position, if its twisted around then problem will still be there. With careful adjustment it can be done, as I say some will be no problem at all.
#18
Dowser,
Dont dip your hand in a tank full of petrol. Dipping your hand into a tank of petrol is not cool!
Seriously, petrol is dangerous, poisionous stuff which can potentially cause death in a matter of minutes, or less. Petrol is small enough to pass through skin directly into the bloodstream, potentially causing liver failure in not much time flat.
Moray
Dont dip your hand in a tank full of petrol. Dipping your hand into a tank of petrol is not cool!
Seriously, petrol is dangerous, poisionous stuff which can potentially cause death in a matter of minutes, or less. Petrol is small enough to pass through skin directly into the bloodstream, potentially causing liver failure in not much time flat.
Moray
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Thanks Moray - so I was clever then?
I'm still amazed at the temp of the OE pump after it had been standing idle in a tank full of petrol for an hour. I can only assume the petrol was also hot....must check to see if better now...
Richard
I'm still amazed at the temp of the OE pump after it had been standing idle in a tank full of petrol for an hour. I can only assume the petrol was also hot....must check to see if better now...
Richard
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Hi All.
I just installed my walbropump from Mark.
After the trooble i can see You are having i did mount the original filter pickup on the walbropump.
this was a little trooble as the original would point to one side.
What i did was to cut of the thing were you but on the lockwasher then i can be installed in the right angle using a hose clamp.
injoy!.
Skassa
I just installed my walbropump from Mark.
After the trooble i can see You are having i did mount the original filter pickup on the walbropump.
this was a little trooble as the original would point to one side.
What i did was to cut of the thing were you but on the lockwasher then i can be installed in the right angle using a hose clamp.
injoy!.
Skassa
#22
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Today I got the tank low enough that it started starving in a straight line. Then I refitted the original pick up which is longer and sits better in the tank. Then out for a blast and the starvation does not happen.
#23
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i swaped back to original filter on saturday had car near empty
and no fuel starvation now thanks
mikee
[Edited by mikeesingh - 8/13/2002 5:06:11 PM]
and no fuel starvation now thanks
mikee
[Edited by mikeesingh - 8/13/2002 5:06:11 PM]
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