Fuel pressure regulator

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Vwjue73
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Fuel pressure regulator

Post by Vwjue73 »

Hi guys got a 2.1 dj I was wondering if to replace the stock f p r with an adjustable one .Has any one done this and with what results if any I!!and model make and where from thanks.

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Aidan
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Re: Fuel pressure regulator

Post by Aidan »

why mess with it ?

it's a vacuum pressure operated return/bypass valve that automatically reduces fuel pressure (and hence flow) to the injectors at low revs and ensures maximum fuel pressure (and hence flow) at high revs and the ECU maps are programmed to match

the pump just pumps at a steady rate and the injectors pass a steady rate at any given pressure so the regulator in combination with the ecu operating the opening and closing of the injectors is what gives the engine the driveability and economy

Too much pressure and you'll get unburnt fuel and too low pressure and you'll run lean, unless you can programme the ecu to match a different pressure (and hence flow rate) you won't get any advantage

I've driven a 2.1 with a blocked plenum vacuum hose and it was pretty undriveable at low speed because the fuel pressure was too high and it was outside the range that the ecu could cope with by reducing the injector opening times or altering the spark timing (MV with lambda so the ECU knew it was running rich)

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