minho78

I'm trying to track down a problem with a lean condition:
What PSI should be at idle with a 2.5 bar FPR installed 4 months ago.
How much should it rise as I give it gas?
I wanted to add that my vaccum reads between 18 and sometimes up to 24hg.

minho78

Anybody could take a look at their gages please?

schip43

If you have a AFR gauge WB or NB you can set it to idle at 14.7, mine was reading lean suddenly, no piggy back and I found that the nut had backed off my AFR. I adjusted it a quater turn at a time till I was back to 14.7 at idle.

Don't have a Fuel Pressure gauge on my mine so I can't give you a number for FP.

Bri Bro

Test procedure:

minho78

Thanks guys.
Brian Ok from what I read I looks like I'm OK at idle 2 bar(~29psi).I thought It had to be at 2.5bar.
I can't get rid of this lean condition.

Bri Bro

Stock AFM? If it is, that is were I would look next.

minho78

Brian APE MAF. I need to check the third step.

Chris White

lets see....what pressure should a 2.5 bar regulator have...hmmm…let me guess – 2.5 bar! Yep, its that easy!
OK, not really – you have to disconnect the vacuum line ot the FPR to get the correct reading. It should be extremely close to 2.5 bar (35 psi). I always though the 2.3 to 2.7 range was too big. I would not be happy with 2.3 bar on a 2.5 regulator.

minho78

Chris when I take the vaccum it goes to 39 PSI on my gauge.

Bri Bro

A 39psi reading is 2psi over 2.5bar, how sure are you of the calibration of the fuel pressure meter? I would guess that higher fuel pressure would make it run a bit richer, not leaner.

minho78

Correct, I have toperform the last step to see if the pump is faulty. Fuel meter is the lindsey fuel meter. Question If I"m reving the engine to get into boost I should see fuel pressure rising?

schip43

Are you running the stock injectors?Maybe you need a 3 bar regulator?

Bri Bro

Yes, it will rise as vacuum is remove from the FPR ie by removing the vacuum line or by the car going into boost.

hot-J

I set mine at 44psi with the vaccum off the gauge, per Vitesse.

hot-J

And yes the perssure should increase as the boost rises, but if you are doing this at idle under the hood, there is no load on the car and no boost. You need load to see it rise reliably.