Still running lean with AFPR maxed out with +20's

[turbo-baron]

Heres my currents setup ( got the motor in yesterday:) ) 2.5 TI,garret/intercooled, ported exhaust manifold,2.5" swingvalve, +20"s and an AFPR. I was attempting to dial in the A/F today and ended up maxing out the the AFPR and still not getting my narrow band into the green at WOT. Any ideas as to what might cause this?

[Directconnection]

I would think if the gauge isn't working right, you'd have lots of black smoke and running very rich conditions.

I suspect that it might be your gauge, but don't totally assume that your gauge isn't reading right due to my suspicions. Dedicated ground is very important on those, or they won't read correctly. I'd verify that it is reading right by seeing what a scan tool is seeing, instead.

Also, maybe there's something wrong with the AFPR? Faulty internally, or.... not hooked up properly?

[turbo-baron]

It puts out some black smoke when you first start it. I believe the gauge is ok because as I was adding more fuel and getting the gauge from lean to stoich I was getting more power. Installing the regulator is pretty idiot proof so I think thats ok. Ill double check the ground in the morning but I'm pretty sure that isn't the problem either. Is there nothing else that might cause this other then a faulty regulator?

[Vigo]

I would think if the gauge isn't working right, you'd have lots of black smoke and running very rich conditions.

I believe you're right because my aries has a problem which i think is grounding all the injectors wide open, and with +20s and stock fuel pressure it goes so rich that it floods out and dies even at 7psi of boost. (<9:1 on wideband).


to the OP:
It could be that your computer is not commanding enough injector pulsewidth when you're in boost. That could cause you to stay on the lean side even with your fuel pressure jacked up. Do you know how to bench-test your map sensor?

[turbo-baron]

How do you bench test the map?

[Vigo]

Well actually i guess bench test is kinda the wrong term here.

Basically what im talking about is feeding the map sensor a fake vacuum/boost signal that you make with a hand pump or whatever else, and then watch the output voltage to see if it is where it supposed to be at that pressure.

For example, if you've got a stock map sensor and you feed it 14 psi and it only sends back 3.0v, that's not right. I have charts for pressure vs voltage if you wanna try that.

Basically all you do is leave the map on the car with the key on, backprobe or tap into the middle wire to get the signal volts its sending out, and then plug your own air line to it to feed it the pressure signal. Then you just compare the pressure reading to the voltage reading.

All you need to do it is a voltmeter, a paper clip, a piece of vacuum line, and something or things that can generate vacuum and pressure, like this reversible hand pump thats usually used for bleeding brake and clutch systems.

http://www.mityvac.com/hq_images/MV8255.jpg

[GLHNSLHT2]

Ugh, when will people learn not to use Narrowband O2 sensors to tune the fuel in their car.

[turbovanman²]

Ugh, when will people learn not to use Narrowband O2 sensors to tune the fuel in their car.

That's right, because Widebands NEVER fail, :rolleyes:



Anyhow, these are links to test your ox sensor and fuel system-

http://www.turbo-mopar.com/forums/vbarticles.php?do=article&articleid=22

http://www.turbo-mopar.com/forums/vbarticles.php?do=article&articleid=36

[GLHNSLHT2]

My stock narrowband O2 would of passed your test. Guess what, with the wideband hooked up it put out the same voltage between 13:1 and over 9:1. Just because your one car lights up the yellow light on your narrowband O2 gauge doesn't mean it's the same a/f on every car, gauge and sensor. One look at the output wave of a narrowband sensor should tell you that.

http://www.techedge.com.au/vehicle/wbo2/fmd/FMD_curve.gif

[Vigo]

So, just to be specific, you DONT have a calibration that is scaled for those +20s, or you DO?

[turbo-baron]

No I don't have a cal. Would I be better of running the stock injecors with this setup. Again 2.5 TI,Garret/interooler,ported exhaust mani, AFPR.

[turbovanman²]

No I don't have a cal. Would I be better of running the stock injecors with this setup. Again 2.5 TI,Garret/interooler,ported exhaust mani, AFPR.

Stock injectors should be fine to 14 psi BUT that won't solve your problem, if your really lean with +20's, it will barely run with stockers. Use the links I provided to figure out if fuel pump and/or ox sensor are good or bad.

[shadow88]

This is the same as here? http://www.turbo-mopar.com/forums/showthread.php?t=51659

So what is it, lean or rich?
What instrument are you using to determine the a/f mixture?
What is your fuel pressure with the vacuum line unplugged?

[Directconnection]

Ugh, when will people learn not to use Narrowband O2 sensors to tune the fuel in their car.

You have to remember that not everyone has $ to sink into their vehicle. Wideband is soooooo much better, but if you know what you're doing, it will work for you. I'm sure you can't argue what Gus did years ago with just an egt and narrow band.

The AEM kit FWD was selling ot to long ago was a deal... but most widebands are over $300. And... most only have $300 into their car to begin with (home-made exhaust, G-valve, injectors)

[turbo-baron]

I guess amidst the excitement of getting my motor in I neglected to attach the ground from the intake mani to the firewall :o. It seems to be running a bit better now....

[GLHNSLHT2]

You have to remember that not everyone has $ to sink into their vehicle. Wideband is soooooo much better, but if you know what you're doing, it will work for you. I'm sure you can't argue what Gus did years ago with just an egt and narrow band.

The AEM kit FWD was selling ot to long ago was a deal... but most widebands are over $300. And... most only have $300 into their car to begin with (home-made exhaust, G-valve, injectors)


Keep up with the times Steve. Lc-1 setups from Innovate go for under $200 all day long on Ebay. That's money well spent to know exactly where you are.

[GLHNSLHT2]

I guess amidst the excitement of getting my motor in I neglected to attach the ground from the intake mani to the firewall :o. It seems to be running a bit better now....

:lol: gotta have the car put together right before you can tune it :)

[Directconnection]

Keep up with the times Steve. Lc-1 setups from Innovate go for under $200 all day long on Ebay. That's money well spent to know exactly where you are.

Oh I know.... I got the AEM for $199 myself. But to tell you the truth, on a budget with something simple like a T-II Garrett and wanting 18psi boost, I'd chance it the old Gus way. My T-III took a lot of $ to bring things back to snuff... I won't chance that.

[Directconnection]

Glad we could be of help.... in a roundabout way :thumb:

[turbovanman²]

Oh I know.... I got the AEM for $199 myself. But to tell you the truth, on a budget with something simple like a T-II Garrett and wanting 18psi boost, I'd chance it the old Gus way. My T-III took a lot of $ to bring things back to snuff... I won't chance that.

Agreed, especially with a stock cal.