Base Fuel Pressure won't go past 38 PSI----Check your FPR, the spring it break!?!!
 

So I'm finally trying to get my car dialed in and my Aeromotive FPR won't go past 38 PSI.:scratch: If I try to adjust is any further is starts going back down.
Setup includes KG Secondary Rail, 1680 secondaries and Denso Supra fuel pump.

Makes me wonder if you have a bad FPR. Did you buy it used? This is assuming there isn't some kind of fuel pump related problem.

No I purchased it new 6 years ago! :lol: Of course the car has been mothballed off and on a lot through that time. I'm thinking of taking it apart and checking it out.

Fuel filter?

Fuel hoses installed backwards?

What kind of voltage are you seeing at the fuel pump?

Problem i've seen 10+ times is not using radiused pump fittings, normal fittings bottom out in the fpr and block the small hole that leads up where the fpr does its regulation. If you take the fpr apart youll see waht I mean. theres really nothing to a FPR, ball on diaphram plate, spring and allen bolts

The filter is low mileage, but is old. I'll be replacing it anyways later this weekend.

Chuck, the hoses are correct. I have the fuel supply going into the primary rail, the primary rail is connected in series to the secondary rail and the outlet on the secondary rail is connected to one of the two inputs, with bottom port being the return line going back to the tank.

I haven't checked the voltage at the pump yet, but that's my next step. At the same time I going to rewire the pump. I've already had to bypass the relay, so the pump continues to run even in the on position on the ignition.

Bacon, which brand and style fittings would you recommend?

My friend is going to lend me his mechanical gauge to compare with my PLX to see if maybe I have a bad sender unit, which is what my friend thinks it may be.

Jegs work fine just search " radiused pump fitting" Ive seen it happen with the SX regulators more than the areomotive, but usally you will just get super slow reaction to pressure changes....

Whenever I have seen these symptoms it has either been a piece of debris (teflon tape, chunk of rubber, etc) stuck in the ball valve of the FPR....or...the o-ring at the fuel pump pick up blowing by into the tank.

You can try loosening the adjuster nearly all the way, lowering the pressure, while the fuel pump is jumpered, then re-tighten it. This can sometimes clear out a small piece of debris holding the ball open.

Do you think this could be a problem? :lol:
http://img148.imageshack.us/img148/2826/imageuyz.jpg

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FAIL!

Wow, I have not seen that happen before.

Wow, guess that spring is going to be added to the list of things to check on a semi regular basis. lol Glad you found your problem!

i would forward it to aeromotive, they will probably give you a brand new FPR. that's no bueno and can result in blown motors so they will be interested in the failure.

that's alot of moisture in there... try to keep the FPR above the pressure port you are running it off of so that condensation drains back down instead of pooling in the hose. also going to guess you have auxiliary water injection, which i suppose this sort of thing is something else we have to worry about failing, put line filters in place for better filtering of post throttle body accessories.

Wow... how could that have happened?

Nope, put it back together and keep looking

David

WOWzer, I just had my SX apart and looks like the first day I owned it, thats an insane abount of rust/condenstion.

Put that on the list of top weird failures!

Why wouldn't they make it stainless, or at least some sort of corrosion resistance coating applied? Either way, most automotive springs are all rusty on the outside after years of use, and hey don't break. Rust in itself ill actually "seal" the exterior of an oxidized surface. The spring still broke, which is obviously a big problem, and I doubt it was caused by a little rust.

So I finally called Aeromotive today and was told that this doesn't happen often.:facepalm:
On the other hand they were happy to sell me another one for $15+$8 for shipping. :wtf:Hopefully be back in business at the end of this week.

lol, but apparently often enough that they know about it. super lame.

at least it doesn't break the bank to replace...not that you should have to replace it anyways.

Springs are often highly stressed components. Switching to stainless can result in a larger spring with undesirable characteristics.

Of course cost is a major factor, and something you can't see inside the component is usually the last place a commercially savvy manufacturer will spend extra money.

David

Opened up my SX Performance FPR last weekend to drill/tap the top hat for an AN fitting and look what I found. Used since 2003 and about 43,000-miles. Often sits idle for 2 weeks at a time and sat for about 1.5 years, 2008-2010. No auxilliary injection. Located in New Orleans with high humidity. Awaiting a response from SX Performance.

Jack

Hopefully SX's customer service is better than Aeromotive. Looks like I'm going to miss a test and tune this weekend because Aeromotive didn't think it was important enough to send my spring out and instead has let it sit there all week. They could have just Priority mailed it for less and it would have been here by now.

Dam i think i'll be taking my aeromotive apart this weekend to check it.