Motor Cutting Out

[Ca_Silvia]

Copied from another Forum:

CA19DET ran perfectly fine/showed no signs of cutting before.

Put in new Walbro 255

Went to car wash

I cannot drive the car in boost anymore, i can free rev it no problem in neutral but once i start building boost (around 2800-3000) the motor turns completely off. No stuttering, no nothing, just off.

Then i cycle the key and it fires right back up no problem. Pump sounds good, no strange whining.

Last night i had the same problem, used compressed air to dry off under the hood - seemed to work, drove fine around the neighbourhood.

Started the car this morning, didn't get 100m from my house and it cut out.

WTF, should i swap the old Walbro back in? Im stumped

[float_6969]

Are you sure you didn't swap the feed and return lines when you installed the new pump? If you did that, when you got into boost, it would close the diaphram in the FPR, and instead of the fuel pressure increase, it would just cut the fuel off completely, which is what it sounds like it's doing.

[float_6969]

If it turns out that this is the problem, you need to replace the fuel filter and run a BUNCH of fuel system cleaner through the car ASAP. Running the fuel through the system backwards runs unfiltered fuel through the fuel rail, potentially plugging the injectors, and more importantly, flushes all the crap in the fuel filter, back into the tank. You'll also want to get a new pickup sock for the fuel pump, as it will probably be plugged up as well.