Need some help figuring out what my issue is.

I'm having my supercharged s2000 e-tuned by Jeff Evans and we decided that the stock fuel pump just wasn't working for me anymore so I installed a deatschwerks 255lph fuel pump.

After the install is where my issue began. As soon as my fuel level drops under half my engine cuts out under WOT at about 5-6k rpms. Loses all power for a few seconds and then pulls again. With half throttle the car will go up to redline with no cutting out.
With a full tank of gas the car doesn't have any problems going to redline under WOT.

Do I have a faulty fuel pump?

 

Did you install the fuel pump into the stock basket with sock? Or did you replace all of this with aftermarket? Typically the fuel sock pick up point changes relative to the float/fuel gauge reading if you go aftermarket. You end up starving for gas before the gauge reflects an accurate level. A larger fuel pump will consume more fuel anyway so its more possible to starve the engine at a higher fuel tank level anyway, but in more severe cases like this, its becuase the fuel sock either has raised or the float accuracy changed through the pump swap. In any case its very likely not the pump itself.

 

Stock basket was used. Stock sock was replaced with the one supplied with the pump.

The pump is the same size as the oem one and I know the walbro sock gets in the way of the float but the sock on this pump is similar to the oem one and the float clears it perfectly, so I'm sure it's reading the level accurately.

 

I will try to lower the pump a little if the stock basket tube will allow me to(06+ can't use the rubber hose and clamps supplied) and then try to secure the pump with zip ties I guess. Hopefully that'll help fix the issue I'm having

 

Yeah the pick up sock likely got raised obove stock location.

 

Just fill up and see how many litre's you use.

That's a quick indication on how off your fuel gauge is.

If you're seeing half tank but you're putting in 11 Gallons of fuel, something is off

 

My fuel gauge isn't actually off. I can run it to 1 bar and still drive. This issue just happens when I have less than a half tank of fuel.

 

Have you checked your spark plugs? When I was getting some breakup at wot it ended up being the spark plugs.

 

Surge tank....

 

Plugs are a few days old NGK BKR8EIX.. So they're fine. This happened after the fuel pump install and is related to the pump I'm sure.


What is surge tank?