Hello everyone,After changing my fuel lines to ptfe. My car is creating a lean spot around 3.7k-4k rpm during WOT. The tuner is saying the tune is okay. He put many of the fuel on that rpm still it creats lean spot. During cruise, the car bogs on part throttle. The fuel pump hanger gets HOT after doing some of the pulls. The fuel pump also starts to make whining noise at the same time on idle. But the fuel pump sounds normal and idle afr is also okay during the cold start. After doing WOT, it messes up. The boost fuel pump was also dead few days back. So, i had an extra fuel pump. Now, my spare boost pump also disturbing, sometimes it turns on and sometimes it bogs when the second pump turns on. Could anyone help me out what should i look into and solve the problem? I've checked few things which are perfectly fine on the car:No boost leakNo Vacuum leakNo fuel line leakageFpr working fine (38-39) with Vacuum and (43.5) without Vacuum
Cleaned injectorsFuel pump relay is also fineAll the fuse are also okay. P.s. i did a small modification on the return line which is, i connect my ptfe fuel line with nylon fuel line which connects with the stock return line through connectors. Pictures attached above.

My car's modlist:
My car's modlist:

2.3l stroker

Sparktech cdi coils

Kelford 288/280(intake 288/exhaust 280)

Precision 6766 twinscroll turbo kit

Ets 3.5 ti inch exhaust

Ets intercooler (4 inch)

Full blown double pumper(255*2)

Fic 1650cc injectors (high z)


Aquamist methanol injection kit
(4 port)

Jacks 5 speed drag transmission

Sheptrans transfer case

Ams intake f1 manifold

S90 74mm throttle body

Grimmspeed 3 port ebcs

 

It seems like you have already checked many potential causes for the lean spot and bogging issues in your Evo 8. However, there are a few additional things you could consider:

1. Fuel pressure: Ensure that your fuel pressure is consistent and within the recommended range throughout the RPM range. A failing fuel pump or a clogged fuel filter could cause fuel pressure issues.

2. Fuel pump hanger: The fact that your fuel pump hanger gets hot after doing pulls could indicate a problem with the fuel pump or the hanger itself. It's possible that the pump is not able to handle the increased demand and is overheating. Consider upgrading to a higher capacity fuel pump or checking if there are any restrictions in the fuel lines or hanger.

3. Wiring and electrical connections: Check all the wiring and electrical connections related to the fuel pump and fuel system. Loose or damaged connections could cause intermittent issues with the fuel pump turning on or functioning properly.

4. Fuel pump noise: The whining noise from the fuel pump could indicate a failing pump or a restriction in the fuel system. It's worth inspecting the fuel lines and checking for any obstructions or kinks that could be causing the noise and affecting fuel flow.

5. Methanol injection: If you have recently installed the Aquamist methanol injection kit, ensure that it is properly calibrated and functioning correctly. Improper methanol injection can cause fueling issues and affect the air-fuel ratio.

6. Tuning: While your tuner may have adjusted the fueling, it's possible that there could be other tuning parameters that need to be adjusted to address the lean spot and bogging issues. Consider consulting with a different tuner or an experienced Evo specialist to ensure that all aspects of the tune are optimized.