Measuring fuel pressure

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trac
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Joined: Sat Nov 13, 2010 11:43 am

Measuring fuel pressure

Post by trac »

Today I measured the fuel pressure of my EJ20G; got a Walbro 255 l/hr pump installed.
Otherwise standard engine, stock FPR.

- installed a t-piece between fuel filter and engine.

With green test connectors connected and contact on, measured:
- pressure gauge varies with 2 sec. interval from 2,2 bar to 2,8 bar (32 - 40,5 psi).

With test connectors unplugged, engine running idle:
- pressure gauge constantly on 2,2 bar (32 psi).

With test connectors unplugged, transmission neutral, blibbing the throttle:
- upon revving engine to 2000 rpm, pressure gauge goes from 2,2 bar to 2,5 bar and at that rpm (say 2000 rpm) pressure drops to 2,2 bar again (so from 32 psi to 36 psi dropping to 32 psi again).

Didn't do any road test testing the pressure under load (got a broken clutch master cylinder...)

Are these values any good for this engine with this Walbro pump?

Image

Thanks, Bram
BSOD2600
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Re: Measuring fuel pressure

Post by BSOD2600 »

Sounds about right.

The FSM has more details and testing instructions too.

'11 WRX Limited
'94 SS | 3" TBE, 07 TMIC, TD05H-16G, Revtronix Stage 2, Walbro -- Sold
'94 TW | R.I.P.
Legacy777
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Re: Measuring fuel pressure

Post by Legacy777 »

That's about right. Here's info when I tested mine. The regulator is the same between the turbo & non-turbo engines, and should give you around the same readings with the vacuum line on and off the regulator.

http://bbs.legacycentral.org/viewtopic.php?f=5&t=24723
Josh

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