Fuel pump PWM
How do you adjust the fuel pump PWM on the ultimate LS? I’ve got some surging at cruising speeds and I’d like to shut that off. I’m wondering if my relay isn’t latching with the PWM. I’ve got a aeromotive a1000 relayed and figure it’s worth a try, on top of the extra wear of the PWM to a relay. I tried following the instructions, but it’s not the same on my ultimate LS system.
Sorry Pat, the PWM fuel pump control they advertise and detail how to adjust in the manual does not exist.
These systems come with a regular coil & contact relay.
I think they made the change because some aftermarket pumps can be damaged with PWV voltage.
Posts one & two here: https://fitechefituning.com/fitech-efi-tuning-forum-2/topic/ultimate-ls-systems-700xx-information/
Thank you for letting me know!