Fuel system diagnosis

[Turbo6Smackdown]

A few questions about our fuel system. 1. Can you diagnose if the fuel pump's doing what it's supposed to be doing with a wide band and a powerlogger file. 2. If I were to pull this tank and pump and have a look-see, what would I be looking for that could pop out something really bad. I get jacked up wires but anything else that's not totally obvious? Is pulling the tank and pump really hard?

 

[SHADOWII]

1/ If you are recording the fuel pressure, it can give you an idea of the performance of the pump/regulator/injector health.
2/Besides the obvious burnt/damaged wiring/connection, check the adapter hose for deterioration/split and the pickup/sock. Be mindful when handling the housing as to not damage the float/arm/switch or gasket seal.
3/Remove the fuel lines after releasing the fuel pressure(remove f/p fuse and idle until engine dies) and disconnect the pump wiring connecter. Place a floor jack w/a piece of plywood , to protect the tank, under the tank and unbolt the two straps. It's easier w/a near empty tank to manage. You can run a ratchet strap over the tank to hold it to the jack/wood block.

 

[Mr.Spool]

Can you diagnose if the fuel pump's doing what it's supposed to be doing with a wide band and a powerlogger file. 2. If I were to pull this tank and pump and have a look-see, what would I be looking for that could pop out something really bad

this is where having a fuel pressure gauge can really help,so you can see things in real time.logging or observing a wideband is always after the events.

 

[Mr.Spool]

Is pulling the tank and pump really hard?

from a lift its easy from your back its not fun,not a big deal though

 

[Turbo6Smackdown]

this is where having a fuel pressure gauge can really help,so you can see things in real time.logging or observing a wideband is always after the events.

Totally. Was thinking of that kit from full throttle, but in the mean time I was just wondering from a hindsight perspective. Just trying to figure out the whole air fuel ratio and how it reacts inside the engine, and how the sensors measure it. I threw on the ported tb/dog house from steve monroe yesterday, plugged the pcv, and it idled as if God himself came down and blessed off on this bitch. It was like Eric Marshall, Bob Bailey or Cal Hartline snuck in when I wasn't looking and touched it. That got me thinking of how sensors report data, and how slight air leaks can affect slow oncoming boost readings and AFRs. If that little fix affected it, then would fuel delivery affect this type of stuff too?

 

[Pronto]

If you have a Powerlogger and your in a good state of repair and tune you can see changes in the fueling sytem. If the volts are good and the chip is burned correctly etc you shouldn't see the ecm adding huge amounts of fuel as the boost and rpms go up. That can be an indicator of some issue but a pressure transducer is a much more accurate way to see how the system is behaving. If you are going to drop the tank replace the stock lines while you're there.

 

[Turbo6Smackdown]

How do you notice that the ecm is adding fuel in the middle of a run. Ipw's?

 

[Mr.Spool]

Just trying to figure out the whole air fuel ratio and how it reacts inside the engine

remember the sensor reads all the cylinders,pulling the plugs tells you whats happening with each cylinder(you can see which ones are rich and lean),with the fuel pressure gauge you know the fuel is getting to the rail.

 

[Turbo6Smackdown]

Plugs can only be read DIRECTLY after a hard wot, correct? Otherwise combustion erases all but the most horrible signs on the plugs. I've read many plugs and they alllll look identical lol.

 

[Pronto]

How do you notice that the ecm is adding fuel in the middle of a run. Ipw's?

BLMs go way north in a hurry.

 

[Turbo6Smackdown]

Ah ok, that's what I thought. So blm's can move that much in so much a 1 second?

 

[Pronto]

Yup.

 

[Mr.Spool]

Plugs can only be read DIRECTLY after a hard wot, correct?

the best way wot shut the car off pull the plugs.some things will show up after that but only the obvious.

 

[Turbo6Smackdown]

Roger that.

 

[Turbo6Smackdown]

Yup.

Wait, Eric's chips are stuck on 128 for wot runs... sooo.... now what?

 

[Pronto]

No, he burns the chip to match your combo. If it needs adjusting you change the parameters available. If the way he burned the chip is too lean or rich or you changed the combo, the ecm will command the changes to the blm. You monitor those changes and adjust the parameters accordingly. Usually his chips are very close but each engine likes it's own tune so the chip settings may need tweaking.

 

[dank GN]

I have a 0-100 pressure transducer that I was using to recorded my fuel pressure . Pm me if u need one bud .

 

[Turbo6Smackdown]

No, he burns the chip to match your combo. If it needs adjusting you change the parameters available. If the way he burned the chip is too lean or rich or you changed the combo, the ecm will command the changes to the blm. You monitor those changes and adjust the parameters accordingly. Usually his chips are very close but each engine likes it's own tune so the chip settings may need tweaking.

Huh? I just asked if the BLMs can shoot higher right in the middle of a run and you said yes. So if that's true, and I'm not getting any blm spikes in the middle of a run, then I'm good? Can I show you a log maybe?

 

[Turbo6Smackdown]

I have a 0-100 pressure transducer that I was using to recorded my fuel pressure . Pm me if u need one bud .

And thanks Dank, I'm going to do the fuel pressure gauge for now but who knows what the future may hold.

 

[Pronto]

Get the transducer then you can log! Don't think you'll be able to look at a fuel pressure gauge while going 120, you won't.