FP too high?

TYTILIDIE

METH HEAD
Is it possible that if your FP is too high it could cause a lean condition? Im thinking no but thought Ild ask anyway cause I still cant get good 02's on the top end like I had them before.
 

critical

meltdown
Re: FP too high?

It could be possible to overpower the injectors w/ fuel pressure.
That may cause erratic pulsewidth.
But a lean condition, i dont know.
 

Daron

Active member
Re: FP too high?

Describe your method of measuring AF Ratio. What numbers did you have before and what do you have now?
 

TYTILIDIE

METH HEAD
Re: FP too high?

Daron said:
Describe your method of measuring AF Ratio. What numbers did you have before and what do you have now?

On Datamaster, my 02's were at 910 the first month I had my new motor running. Now I cant get over 600 and these #'s are at WOT. I cant run as much boost as I was and even at 15 psi, my 02's are at like 7 something. Im contemplating going back to 2 bar and stock chip and FPR to see what kind of #'s I get. Abe, TURBOTYPHOON69, has the same turbo on stock motor with just and AFPR and a stock chip and stock boost and his 02's are at upper 9's and lower 1000's. He runs a 13.6 on this set up. I run a 13.2 with no fuel. Imthinkinng something is dead wrong here. I should be in the 12's. I dont have a wide band yet and do plan on getting one but for now IM just stuck with DM.
 

SY2455

70's Veteran
Re: FP too high?

What is your current fuel pressure set at? Have you change out your fuel filter lately?
My last filter lasted only 2500 miles. I only use top quality parts and gas so I was wondering what happen. So when I change out the filter again I cut it opened and found it 75% plugged. I must have got the bottom of the gas station tanks before a delivery.
 
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Daron

Active member
Re: FP too high?

TYTILIDIE said:
On Datamaster, my 02's were at 910 the first month I had my new motor running. Now I cant get over 600 and these #'s are at WOT. I cant run as much boost as I was and even at 15 psi, my 02's are at like 7 something. Im contemplating going back to 2 bar and stock chip and FPR to see what kind of #'s I get. Abe, TURBOTYPHOON69, has the same turbo on stock motor with just and AFPR and a stock chip and stock boost and his 02's are at upper 9's and lower 1000's. He runs a 13.6 on this set up. I run a 13.2 with no fuel. Imthinkinng something is dead wrong here. I should be in the 12's. I dont have a wide band yet and do plan on getting one but for now IM just stuck with DM.

Comparing o2 readings are not really productive, when discussing narrow-band sensors. I would suggest the sensor is on the fritz / changing, rather than your actual air fuel ratios. I would swap a new O2 in before I changed anything else.
If you suspect your running too rich, adjust your pressure down in small increments, and when your knock count starts to elevate, go back to the previous pressure setting where knock was acceptable. That will get you into the ball park, pressure wise.
 

TYTILIDIE

METH HEAD
Re: FP too high?

Im at 60 psi right now. I am dropping the tank tomorrow to make absolute sure the hose is ok. After that, I will grab my spare 02 sensor and slap it in. If its neither of those, I may put in my stock injectors. If that doesnt work, Im going to borrow an AFPR and see if thats it. I knwo I had this thiung running very good and just want to get it back to that point.
 

SY2455

70's Veteran
Re: FP too high?

TYTILIDIE said:
Im at 60 psi right now. I am dropping the tank tomorrow to make absolute sure the hose is ok. After that, I will grab my spare 02 sensor and slap it in. If its neither of those, I may put in my stock injectors. If that doesnt work, Im going to borrow an AFPR and see if thats it. I knwo I had this thiung running very good and just want to get it back to that point.

Did you check the fuel filter? I thought with the Ultimate you were to set fuel press at 50 lb. Did you go to 60 lb as a result of more tuning?
 

TYTILIDIE

METH HEAD
Re: FP too high?

Yes I did. Fuel filter is fine. Now Im having a short somewhere and my truck keeps trying to cut off so Ill have to get that fixed before I mess with my fuel problem anymore.
 

It's just a six

Super Member
Re: FP too high?

TYTILIDIE said:
Im at 60 psi right now. I am dropping the tank tomorrow to make absolute sure the hose is ok. After that, I will grab my spare 02 sensor and slap it in. If its neither of those, I may put in my stock injectors. If that doesnt work, Im going to borrow an AFPR and see if thats it. I knwo I had this thiung running very good and just want to get it back to that point.

Instead of all that work, maybe you should buy a wideband reader? :2cents:
 

TYTILIDIE

METH HEAD
Re: FP too high?

I pulled the tank today and the hose looked a little chewed up but am not sure it was causing this problem. Its possible that it wasnt clamped right because when I first did my own 10ga wiring, I didnt have th erelay working irhgt and it wouldnt shut off. Im thinking maybe it pushed the hose down enough to bleed at higher psi. I havent driven it yet but hopefully tonight I will. I just wanted to eliminate that first. Wideband tools are in the future but can not afford it all at the moment. If Im not fixed as of today, I plan on going to the 02 sensor then the rest of the fuel system. This all started when I blew my hose on the pump a few months ago. Before that everything was just fine.
 
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