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Anybody have any idea if this is normal? Went for a drive in this 36c weather and the car was idling at 16afr. Doesn't seem right. I can hear the fuel pump screaming its nut off in the tank. It is much less than a year old. The noise doesn't fuss me but i believe the noise is a side effect from the heat and its performing poorly as the fuel must be hot.

Any suggestions? The last thing i want is the pump failing or not giving enough fuel to the car this summer. It was fine the last time i drove pre bs weather. Its a walbro 255l drop in.

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Was it noisey from the moment the car started or did it develop during the drive?

If it was noisey since it started, I wouldnt suspect heat. Unless you have a fuel cooler, it will probably get about as warm as it was on startup just cycling through the system.

A genuine Walbro 255 shouldn't scream, unless it's under massive stress, such as 80+psi fuel pressure, or high temps as you mentioned.

Have you got under the car and felt the fuel tank? It was 40 odd degrees yesterday wasn't it?

It developed to the point I could hear it while cruising. Electronics generally do not like heat, they don't perform as efficiently. Does this still apply with the pump?

Its genuine, I bought it off you. Its heat related. The car will not do it when it starts but builds up to it. Tomorrow should be about 15c cooler than today so will test and see what happens. Noise I can live with but the afr's changing so drastically(from 13.8 idle to 16.7) isn't good. Seems only to affect idle though.

Would beefing up the wiring further help?

I've done the grounding mod. The pump never has an issue. Voltage is stable in the vehicle. I've beefed up the grounding wire and I think I also beefed up the wiring in the tank but yeah essentially just grounded the pump control module.

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