Join Date: Dec 2013
Feedback Score: 0 reviews
Stock Fuel Pump Problem??
Hi all. I'm in the process of getting my 1.7T back on the road.
I figured I'd check the injectors before I bolt up the intake manifold. I jumpered at the main relay to turn on the fuel pump, then applied 8.5V to each injector for 15s to turn them on, one at a time.
I ran a hose from the fuel pressure regulator to a gerry can for the extra bypassed fuel.
I found that in 15s I injected approx 100mL. They were matched +-5ml which made me happy. A little low for the quoted injector size (500) but 400 is in the ballpark at least.
Without the injector firing I noticed the output from the regulator was surprisingly weak. A trickle. I measured this at 250mL/30sec, multiplying out to 500mL/min, 30L/Hour.
When I turned on the injector the bypassed fuel all but stopped.
Is this normal for a stock pump? I guess the next step is to check the filter. Not long ago I checked it and it was fine...I don't have a great way to check fuel pressure...sucks it doesn't have a fuel rail test port like a GM/Ford. They did one thing right lol.