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  #1  
Old 11-27-2003, 11:36 PM
6evil9
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checking fuel pump and pressure regulator

Hi

how can i check if fuel pump and pressure regulator work fine?

what pressure should fuel pump make?



(my car dies slowly with terrible idle and terrible acceleration under 3000rpms i wanna cry )
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  #2  
Old 11-28-2003, 10:47 AM
lee lee is offline
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Location: Indialantic, Florida
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with a gauge made for this, do it at the tank outlet under the rear seat area. my reference says 34-38 psi regulator disconnected, 26-30 connected.
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  #3  
Old 11-28-2003, 04:08 PM
6evil9
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what does regulator connected/disconnected mean?

how do i do it?

and that pressure should be at idle?
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  #4  
Old 11-28-2003, 04:23 PM
lee lee is offline
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sorry, told you wrong place, read this

Fuel Pressure: Testing and Inspection
1. Release fuel pressure.
2. Install fuel pressure gauge.
a. Disconnect fuel hose from filter.
b. Connect fuel pressure gauge between hose and filter.
3. Start engine.
4. Disconnect vacuum hose from fuel pressure regulator.
5. Observe fuel pressure reading.
Fuel Pressure
235 - 265 kPa (2.4 - 2.7 kg/cm, 34 - 38 psi)
6. Connect vacuum hose to fuel pressure regulator.
7. Observe fuel pressure reading.
Fuel Pressure
177 - 206 kPa (1.8 - 2.1 kg/cm, 26 - 30 psi)
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  #5  
Old 11-28-2003, 07:10 PM
6evil9
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cheers

ill have it checked ....hope mechanincs here have the pressure gauges...

thx
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  #6  
Old 12-02-2003, 08:09 PM
James Scott James Scott is offline
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Join Date: Nov 2002
Location: Fresno, CA
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Exclamation doiturselv!

U can do it ur self! Buy fuel press gauge. Cut gas line (out from fuel filter) in half. Get T fitting to hook up gauge. If like mine ($24.95), will reach (barely) windshield (under windshield wiper arm. Support with plastic or wood scrap to prop up gauge, so you can see it thru windshield from driver's seat.

Like they said, 26-30 lbs when vac line attached, 34-38 lbs when you pull off (tiny) vacuum hose (passenger side rear of engine, near fuel rail). When driving, fuel pressure will vary from 26 to 38 lbs pressure (has to do with vacuum loss at high speeds?)

I drove for about a week, to see if fuel pressure would vary (drop) significantly when my intermittent rough idle problem or high-speed shuddering surfaced. The problem showed up, with no change in fuel pressure. You can do the same, if U want!

Good Luck! [I'm doing the same with a vacuum line now, to see if it's the problem. I'm also waiting for another member to swap MAF sensors to see if that could be the problem.]
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Last edited by James Scott; 12-02-2003 at 08:12 PM.
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  #7  
Old 12-02-2003, 10:41 PM
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sleepem sleepem is offline
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Location: East of Mount Vernon, WA
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Lightbulb check your hoses

I recently had the same type symptoms after removing a couple of the large hoses that go into the airbox at the back of the engine. I left one off and got no idle and ran ratty below 2500 rpm.Noticed the hose off and put it on and had instant fix. My guess is that a lot of air bypassing the MAF thru the hose leak kills the idle. Several of my hoses were so hard that they broke like glass when I pulled them off, so yours may have a leaky hose, especially under the intake manifold where they're hard to see. This may be too simple but hope it helps!

Rob
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  #8  
Old 12-03-2003, 03:35 AM
6evil9
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so what rpms are for what pressure?

i think pressure will vary with rpms?

any simple table from 3-4 readings it should have?

and yes ofcourse i started from vacuum lines

i ve changed almost all hoses i could find

but still no luck

what hose r u talking about Rob? cause there are 5-7 of them
and they give different result

(like big one off throttle body on the top: when removed car just dont iddle at all!)

also i hear some whistling noise from around the power steering pump/reservoir, checked hoses there but they seem to be ok

removed manifold and changed couple of hoses under it, but on the vacuum diagram, there are 2 more...

geez how its hard to change them! (gonna take alternator next time to get access. as removing manifold and putting back manifold is 2 hour job... )
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  #9  
Old 12-03-2003, 10:27 AM
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sleepem sleepem is offline
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vacuum lines

A leak in any line anywhere that terminates on the airbox would be suspect. Some are very hard to see or inspect under the intake spider, tho.

The whistling near the PS pump could be a leak at an intake riser...loose bolt? or missing gasket. This may also give same symptoms as leaking or disconnected hose.

Just my thoughts...you prolly have checked this..

Rob
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