Wideband vrs Narrowband readings?

[andy670ho]

SO I finally hooked up my hptuners to my wideband and went to make a little run and see where I am at, According to my wideband I am very lean, can you tell from the narrowband readings if my wideband is reading right? I am fighting a losing battle with my walbro 255, I put a hotwire kit on it today but it is still dropping to 51 psi at wot and not coming back so I think my pump is going. Can someone look at my log and see if my narrowbands are reading lean under wot?

[KLUG'S SS]

DO NOT pay any attention what so ever to what your narrowbands are reading at WOT!

Narrowbands are not accurate at all at WOT. They are good and accurate around stoich and that is it period.

[KLUG'S SS]

From that log I seen that your wideband was reading at almost 13.8 at one point in that WOT run which is wayyyy too lean at wot.

What wideband do you have? Did you check to make sure that you didnt have any voltage offsets so that your wideband matches what it is reading in the scanner?

Thats not too good on the fuel pressure at wot either.

[Cantalope Kid]

Well thats your culprit right there then. Lost fuel pressure. How are you confirming 51 psi vs. stock 58 psi? Anyow fix the fuel pump issue first. Mechanical THEN tuning... Don't see a copy of your tune but guessing your haven't changed your PE setting to command a 13.8 AFR @ WOT. Your losing pressure when its trying to hit the figure you are commanding. 13.8 is F*ing horrible! Stay out of it and get back to 58 psi rail pressure.

[Cantalope Kid]

Did you also notice you were at 41* ignition advance from 4300rpm on down when you let off the gas?

[andy670ho]

I have a fuel pressure gauge in the car also, the car was always rock solid when in PE at 12.9 afr until I noticed a drop in fuel pressure, thought it was voltage related so I went with the hotwire kit but it didn't help the problem so a pump is on order. Is the timing a little high when letting off? I have a plx wideband and the gauge and hp tuners is very close if not spot on, I have noticed this lean condition when entering PE on my gauge. Is there a way to log my fuel pressure with my autometer electric gauge?

[Cantalope Kid]

Timing just threw me for a loop since this is not the amount of timing you have given the vehicle in your HO tables. Look at your scanner when you let out. I think your commanding like 31* if I recall correctly (don't have Hp Tuners at work to view). Somewhere (decel maybe) you are getting an additional 9*-10* being added in when you slam the throttle shut.

[blownbluez06]

Is there a way to log my fuel pressure with my autometer electric gauge?

There is a way to log virtually any 0-5v input and even 0-100v inputs with a custom built and scaled circuit.
You need to discover the scale of the output of the sending unit and then you can write a custom PID for it. Do you have HPtuners pro? If so, just use one of the EIO inputs and scale it to match the sending units' output.

[KFZ)^]

If you have the HPT Pro MPVI interface, the Autometer Fuel Pressure Gauge is pre-configured in the Scanner AUX Input list, under Fuel.