GS400 started acting up on Sunday. Car would idle real low and shut down. Would restart it and hold the throttle open slightly to keep it idling, and as it warmed up it returned to normal.

I did a spark test and I am getting spark, so that means I am not getting any fuel.

I cannot hear the fuel pump priming, replaced EFI relay which did not fix the issue.

Swapped ENG MAIN relay, no success. Attempted to bypass the fuel pump ECU and the car still will not start.

Is there anything else I should check before replacing the fuel pump? And what wires should I be connecting on the fuel pump ECU in order to bypass it correctly? I found the two think wires running directly to the pump, so I jumped those at the fuel pump ECU, but I had no success.

Thank you ClubLexus.

 

are you 100% sure the fuel pump isn't running? Generally, fuel pumps in Lexus' are extremely quiet...

There are other potential issues than just fuel if you are getting spark...

I'd put a fuel pressure gauge on that before I just guessed and replaced the pump...

 

Fuel pump is getting power when I crank on it.

Replaced fuel pump, car starts. Thank you.