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84 stalls in a hard turn when under 1/2 tank of fuel

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84 stalls in a hard turn when under 1/2 tank of fuel

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Old 06-13-2018, 07:28 AM
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Gibbles
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Default 84 stalls in a hard turn when under 1/2 tank of fuel

So my 84 stalls in a hard turn when under 1/2 tank of fuel.
it got a bit worse after my fuel pump upgrade.
While data logging or ve learning with my ebl flash, it also runs noticeably leaner...

I understand that some have resolved it by adding a cup around the fuel pickup...

​​​​​​​Anyone have a good solution (and maybe pictures)?
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Old 06-13-2018, 01:23 PM
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Originally Posted by Gibbles View Post
So my 84 stalls in a hard turn when under 1/2 tank of fuel.
it got a bit worse after my fuel pump upgrade.
While data logging or ve learning with my ebl flash, it also runs noticeably leaner...

I understand that some have resolved it by adding a cup around the fuel pickup...

​​​​​​​Anyone have a good solution (and maybe pictures)?
My 85 does the same. Replacing the fuel sock helped quite a bit, it won't stall until ~1/8th of a tank now. I have EBL Flash as well, I love it. It does lean out as you turn hard because the pump isn't keeping fuel pressure high enough. For me, it would stay lean until I let off the throttle, as the pump couldn't bring the pressure up until DC was low.

If a new sock doesn't help you, then a cup/baffle may be a good idea - if mine stalled below half a tank, I'd get annoyed quick. But since mine won't do it till the tank is down to the last few gallons, I just avoid hard driving below 1/4 tank. I unfortunately don't have pictures, but my '78 LTD had serious fuel-sloshing issues, so I fashioned a brass bowl that I tacked to the sending unit such that the bowl was right below the pickup on the sender. The bowl itself started as a sheet of brass, I shaped with a hammer and piece of round steel-stock. I soldered it shut on where the edges met, then attached it to the sender using coat hanger wire that I dipped in rust inhibitor (old car doesn't have a pressurized gas tank, so air/moisture can get in).
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Old 06-13-2018, 06:48 PM
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Sock is about one year old, i swapped it when i changed a tail light last year. (Easy access with the pump out).

It got really bad after i re plumbed the throttle bodies to include the vac ref fuel pressure gauge.

​​​​​​​its pretty anoying not being able to run less than a half tank...
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Old 06-13-2018, 06:59 PM
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I also noticed the fuel return points away from the pump/sock.
​​​​​​​i keep wondering if it would help if i redirected it towards the sock, or if that would cause more issues.
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Old 06-13-2018, 07:33 PM
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ex-x-fire
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Get one of those Holley fuel pump socks, they pick up fuel even if a corner is submerged.

Last edited by ex-x-fire; 06-13-2018 at 07:34 PM.
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Old 06-14-2018, 10:41 AM
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That sock looks like just the ticket.

What I don't see is a way to attach that to my fuel pump with the press on sock type.
I'm not sure if I would have enough room to adapt it to the AN fitting type.

It also looks like I would likely need to cut out the OEM fuel bowl mounted in the bottom of the tank, but that should be no problem.
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Old 06-14-2018, 02:21 PM
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I find it hard to believe that you could be sucking air at your fuel sock with a half tank of fuel. Yes, '84's do real good in the corners, but you'd need to be pulling about 2 g's or so to suck air with a half tank of fuel! There must be something else going on here.

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Old 06-14-2018, 02:38 PM
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Originally Posted by Hot Rod Roy View Post
I find it hard to believe that you could be sucking air at your fuel sock with a half tank of fuel. Yes, '84's do real good in the corners, but you'd need to be pulling about 2 g's or so to suck air with a half tank of fuel! There must be something else going on here.

Good point, could be a leak somewhere in the plumbing above the pump has a rust hole? Does yours have the silly pulsator? It could suck in air there too if the seals were shot.
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Old 06-14-2018, 03:51 PM
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I've pulled some pretty ferocious g's in my '84, but it just kept asking for more!! I probably need some stickier tires to test your theory, as I went into a sideways slide, but the engine was running fine! A helmet is recommended for that test, as I kept banging my head on my roof frame!

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Old 06-14-2018, 04:16 PM
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no pulsator, and its a new pump as of a few years ago.
All is pretty good cond
and the fuel line between the pump and the pump frame thingy is tight and the correct type of line.

I started to wonder if maybe the holes that allow fuel into the fuel tank bowl/anti slosh thingy is too small for the amount of fuel that's getting sucked up.
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Old 06-14-2018, 04:43 PM
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Originally Posted by Hot Rod Roy View Post
I've pulled some pretty ferocious g's in my '84, but it just kept asking for more!! I probably need some stickier tires to test your theory, as I went into a sideways slide, but the engine was running fine! A helmet is recommended for that test, as I kept banging my head on my roof frame!

My first doughnut ever ended in my engine shutting off at the end.
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Old 06-14-2018, 04:45 PM
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I also finally found am active picture of an oil bottle used to keep fuel sucking, i might give it a test this weekend if i have the time
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Old 06-15-2018, 05:02 AM
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Did you check the tank for the factory baffle / cup mounted in base of tank, the fuel pump sits there and if the cup has come loose that will explain the fuel starvation issue.

My 85 had the same symptoms when i got it, the cup fuel pump recess thing had come loose. It will not stay there if the plastic welds have broken, i ended up attaching it to the fuel pump /sender assembly.

Is a pain to get right but its cable tied to the sender piping and a bit tricky to fit in tank, but have not had any fuel starvation issues.

Just too lazy to replace the tank
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Old 06-15-2018, 06:58 AM
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Thanks, and yes the cup is in the tank.
it's riveted very solid to the bottom.
And i think i forgot to post the year, it's an 84.

Some of the pictures i saw searching around showed the baffle bowl thing with straight sides, the ome in my car is more of a bowl \_/ on the sides.
And yesterday, driving onto a freeway onramp with a nice s shape, i drove a bit spirited with just under 1/2 tank and it tried to stall.

it sure takes the winds out of your sails, jaring me into the seatbelt pretty good.

I'm thinking oil bottle around the pickup, and changing the fuel return to aim at the pickup/oil bottle since right now it aims at the left rear corner of the tank...
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Old 06-15-2018, 10:40 AM
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Before I changed to a fuel cell, I used a piece of braided steel line from the end of the fuel pump to the bottom of the fuel basket. You can configure this so it comes within a 1/2" of the basket. I used a hose clamp to clamp the line to the pump. Something must be wrong with your setup and you are sucking air somewhere.
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Old 06-15-2018, 11:05 AM
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I was planning on tearing into this weekend, however I just filled up my tank yesterday.
I'll have to keep a mental note next weekend to not fill up my tank so I can take a good solid look at my setup.

Also, thoughts on the fuel return line?
Is it odd that it's aimed away from the fuel pickup?

I noticed in my wife's 2007 aura when I changed the fuel pump, there are 0 baffles inside of the tank.
And the fuel pump assy has this box that has a hinge.
Inside of the box the fuel pickup and return are included, along with the fuel strainer.

I have yet to do a full dissection of the old unit, however I kept it as I might learn something from it.
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Old 06-15-2018, 11:41 AM
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Originally Posted by Gibbles View Post
I was planning on tearing into this weekend, however I just filled up my tank yesterday.
I'll have to keep a mental note next weekend to not fill up my tank so I can take a good solid look at my setup.

Also, thoughts on the fuel return line?
Is it odd that it's aimed away from the fuel pickup?

I noticed in my wife's 2007 aura when I changed the fuel pump, there are 0 baffles inside of the tank.
And the fuel pump assy has this box that has a hinge.
Inside of the box the fuel pickup and return are included, along with the fuel strainer.

I have yet to do a full dissection of the old unit, however I kept it as I might learn something from it.
My only concern with the fuel return would be that it could introduce air into the gas depending on how you set it up. If the return was under the gas level, I think it would help. But if it dumps fuel from the top of the tank, I'd worry a little about air bubbles. Probably not a huge issue, but maybe worth considering.
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Old 06-15-2018, 08:29 PM
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Originally Posted by Gibbles View Post
Sock is about one year old, i swapped it when i changed a tail light last year. (Easy access with the pump out).

It got really bad after i re plumbed the throttle bodies to include the vac ref fuel pressure gauge.

​​​​​​​its pretty anoying not being able to run less than a half tank...
Why vac ref?
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Old 06-16-2018, 01:16 AM
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Originally Posted by JoBy View Post
Why vac ref?
That's a good question. What's up with the re-plumbing? There's no vacuum referenced fuel pressure regulator in the CFI system. What is your fuel pressure? Does the fuel pressure at your throttle bodies decrease as the fuel level in your tank goes down?

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Old 06-16-2018, 01:34 AM
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Originally Posted by Gibbles View Post

It got really bad after i re plumbed the throttle bodies to include the vac ref fuel pressure gauge.

​​​​​.
I agree with the two previous posters. What did you do? If it made it worse, put it beck to stock.
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