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-   -   Fuel Cutout @ High RPM in 4th Gear (https://www.ft86club.com/forums/showthread.php?t=155352)

smoltz 05-05-2025 01:19 PM

Fuel Cutout @ High RPM in 4th Gear
 
Anyone here experience fuel cut out at high RPM on track? Stock FA20 w/ Tune+Headers.

This was on a straight after a mid-g left hander.

I had about 3/4 tank of fuel, maybe a little less. Getting what I suspect was fuel cut out at high RPM in 4th, felt like I was hitting the limiter but I wasn't even close to it.

Is there a good way to verify this? Other than just replacing/upgrading fuel pump.

I see some older bosts about flapper mods and such but seems like DW300C fuel pump is the permanent solution?

Thoughts? Suggestions?

NoHaveMSG 05-05-2025 09:29 PM

Left hand turn. Fuel pump/pickup is on the left side it’s even worse with e85. The Verus fuel door helps some.

smoltz 05-05-2025 10:37 PM

Quote:

Originally Posted by NoHaveMSG (Post 3613779)
Left hand turn. Fuel pump/pickup is on the left side it’s even worse with e85. The Verus fuel door helps some.

What's the "proper" fix here?

14stu 05-05-2025 10:47 PM

Quote:

Originally Posted by smoltz (Post 3613781)
What's the "proper" fix here?

The Versus flapper valve lets you run longer without fuel cut, but to completely fix the issue you'd need a surge tank, auxiliary or transfer pump, or fuel cell.

smoltz 05-06-2025 07:30 AM

Maybe I'll start with the Verus flap and go from there.

This is a video of what's happening....

https://youtu.be/DVdzbvB68pc

In the video you'll see throttle goes to zero but that's cause I'm logging TPS not PPS (although I think I have the data for that in another file). I am 100% on the pedal. Seems like fuel starvation, car cuts throttle?

Is there any way to confirm that it's fuel starvation?

NoHaveMSG 05-07-2025 05:54 AM

Quote:

Originally Posted by smoltz (Post 3613787)
Maybe I'll start with the Verus flap and go from there.

This is a video of what's happening....



In the video you'll see throttle goes to zero but that's cause I'm logging TPS not PPS (although I think I have the data for that in another file). I am 100% on the pedal. Seems like fuel starvation, car cuts throttle?

Is there any way to confirm that it's fuel starvation?

That doesn’t sound like fuel cut to me. When it fuel cuts on my car it feels like it bogs. It also usually fuel cuts mid corner to track out depending on corner type/length. That sound kinda reminds me of bad DI seals. What do you have for logging data on car?

smoltz 05-07-2025 08:56 AM

Quote:

Originally Posted by NoHaveMSG (Post 3613820)
That doesn’t sound like fuel cut to me. When it fuel cuts on my car it feels like it bogs. It also usually fuel cuts mid corner to track out depending on corner type/length. That sound kinda reminds me of bad DI seals. What do you have for logging data on car?

Interesting. This was happening at the end of a short straight after a left hand turn, and I made it out of the turn through the top of 3rd into 4th with no issues. It did the exact same thing multiple times, but only at top (6500+) of 4th.

While on track it was just my AIM running with stock ECU profile, so not much, just pedal position, throttle position. Car has stock ecu with ECUtek so theoretically if I can reproduce I can use their logging feature.

Assuming I could get the ecutek logging setup and reproduce what should I be looking for?

NoHaveMSG 05-07-2025 03:07 PM

Quote:

Originally Posted by smoltz (Post 3613821)
Interesting. This was happening at the end of a short straight after a left hand turn, and I made it out of the turn through the top of 3rd into 4th with no issues. It did the exact same thing multiple times, but only at top (6500+) of 4th.

While on track it was just my AIM running with stock ECU profile, so not much, just pedal position, throttle position. Car has stock ecu with ECUtek so theoretically if I can reproduce I can use their logging feature.

Assuming I could get the ecutek logging setup and reproduce what should I be looking for?

I’d talk to your tuner and see if he is willing to help you setup logging. If not someone else should be able to help you from here. You should be able to log it. I’m an OFT peasant so out of my wheel house.

ZDan 05-07-2025 08:03 PM

Um, I had a similar issue, chased "fuel starvation", installed flapper valve, no joy. turns out the tune cut power if oil temp went above 275F! Dam... So yeah, check with tuner...


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