Whats up with my A/f ?

#21
Check fuel pump duty cycle
Check pressure drop accross injectors
Check injector duty cycle

You NEED to datalog WOT to see if your pumps are maxing out...its unlikely that they are done at just part throttle. Just run to about 4 PSI and check the results and report back. I can compare them with my car @ around 4PSI and see at a given fual rail pressure and injector duty cycle, how much fuel will be actually going into the motor.

your best bet for teh WOT run is to pull 4 * of timing from the 2000-4000 and 6*s from the 4000-8000RPM ranges...your car will be a dog, but it will be rediculously safe....even with a really lean A/F. Just dont rev it enough to get over 4 PSI and you will be fine.
 
#24
Sorry that took so long, got busy with other things haha.. anywho here is what I found out.

You need to actually plug the Xcal into the laptop first and then into the car, otherwise you wont be able to find those settings. I tried finding them based off my EEC code, but it wasnt there.

Ill look tomorrow once I plug it into the car and ill tell you exactly where they are located.
 
#27
So I tore the car apart today to see if I could find any cause of the lean condition. I checked all of the intercooler pipes, all the hose clamps, the MAF, EtC.

The only thing I found was I blew to tube clean off my PCV valve and there was oil on the valve cover. So I took this opertunity to run down to lowes to grab some things to make an oil seperator. It doesnt look the cleanest, but it does its job.

DSC01559.webp


Its icy here, so now WOT datalogs today. But as soon as the streets are dry I will go at it again. Help/suggestions are still welcomed :)
 

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#28
I logged those setting I was telling you about....but scratch the injector dutcy cycle, that wasnt in there...just pulse width.

So go into

+fuel
+Fuel pump

and you will find the "pressure drop accress injectors" and "fuel pump duty cycle" under those two sub headings. Those two in particular are I belive under the FUEL PUMP sub heading.

If you want Ill upload my datalog to SCTs site and link you to it so you can look at it on live link to get an idea of what you need to log and how everything should look...I logged ALOT of parameters. Just let me know.
 
#31
i wish i woulda saw this thread earlier

ive had a horrible experience with chris, and whenever something is wrong, as far as he is concerned you are pegging the maf, and he will try and sell you a new one until he is blue in the face, try and convince you the car isnt drivable, and make you think he is the best in the world. dont use him atall, he is worthless trash, he doesnt know tuning for *****. best bet is to either A) datalog B) go to kansas city or oklahoma. you might even be able to get a local guy around here to tune it(i got a good friend who taught chris how to do alot of tuning, who doesnt like him anymore do to the way he treated me at his shop). if you do go to his shop, be ready to pay big bucks, he charged one guy 1900 bucks for a LT install, subframe connectors and a base tune on a TA. figure 500-700 for the install, 100 for the subframe connectors, where did the rest go? i would explain a little bit better what happend to me but it really just makes me mad, lets just say we agreed on a price, got there, he dicked around for about 4 hours, told me my chip was bad, told me i pegged a L MAF, all with 6lbs of boost through a powerdyne... odd if you ask me
 
#33
nesqwick_05 said:
and its good to see more mustangs from wichita, esp. ones that are modding constantly. we shoud go on a cruise sometime in the spring...
Click to expand...

hell yes!

I thought something was off with him as soon as he said right away I needed a new MAF from him. I am considering getting the pro racer package and the book that MD sells so I can learn to tune my car myself. I graduate college next weekend, so this will give me something new to learn.

I am really glad to see another mustang guy in wichita, I'd like to hear more of your story. I was thinking about going down there just to get some numbers and to see if my car REALLY is running lean. But I dont know how accurate their dyno or A/f Is.....
 
#35
Couple of things... You are only guessing until you datalog things - like they said, log FP duty cycle and pressure drop across theinjectors - also log MAF AD counts and see where they are - if you are pegging the MAF, which I doubt - the counts will be at or approaching 1023. Be sure to use the latest version of LiveLink also. You can tell if your injectors are maxed out by logging injector PW - what happens is as the revs go up, the PW increases, when the injectors are done, the RPMs go up and the PW stays static. But again, I doubt this is the case.

An exhaust leak can show a lean condition - but 99.9% of the time this is at idle and to a lesser extent at part throttle and the reason for this is simple - the exhaust leak is usually a fixed volume of leaking air diluting the exhaust gases, but as RPMs rise, the leak becomes a much smaller percentage of the total gas volume, so it becomes much less apparent.

My guess is you have a bad WB sensor, although it could be something else. The sensors for most of the cheaper widebands are basically used for VW Turbo Beetles and you can get them online for $45 or so, so replacing it isn't that bad.

One other thing to consider is in some rare instances an overly rich condition will show as lean on a wideband and that's because the 02 sensor is reading the oxygen in the raw gasoline. It happens.

Usually at 18:1 there isn't enough energy in the mixture to hurt much and the car would not run "good" at WOT, you'd have hesitations and dead spots, so I question the readings, but like I said anything can happen. I'd replace the sensor and do the logs as suggested. Switching bank to bank helps also to give you more info - when we tune cars we run a wideband in each side usually.

Lastly, if you do get the PRP package, I would not waste your $$ on the PRP manual. Strange coming from me, because I wrote it for SCT. The problem is it has not been updated in a long time and it contains mostly older SCT hardware. There is some good tuning info in it, but it probably is not worth $75. Hate to plug ourselves, but I will anyway :D we have been selling Pro Racer training videos that show you, in the software exactly how and what to datalog and then how to apply this to the tune - there are over 10 hours of training on each disk - 5 for each version of SCT's Advantage software. We have sold a ton of them and one comment I keep hearing is that SCT should have included it with the software. We include it for free when we sell the PRP software and hardware to someone and discount it when someone gets just the software from us. See link in sig for more info.

Don
 
#36
Well, I just bought the wideband. I am going to call AEM and tell them I need a new sensor.

I am thinking I might have ruined it when I blew off my intercooler pipe and the computer was adding fuel like crazy. You could TASTE the gas in the air...hehe

There is ice/snow all over the streets- once that goes away I will datalog all day long :)

So far all signs point to a bad a/f sensor....
 
#39
SilverBullet00 said:
Well, I just bought the wideband. I am going to call AEM and tell them I need a new sensor.

I am thinking I might have ruined it when I blew off my intercooler pipe and the computer was adding fuel like crazy. You could TASTE the gas in the air...hehe

There is ice/snow all over the streets- once that goes away I will datalog all day long :)

So far all signs point to a bad a/f sensor....
Click to expand...


Tims tunes from MPH are usually dead on , I wouldnt do anything until you replace the sensor , and you might want to make sure it doesnt show -- when it goes lower than 10.0 either , my autometer wont read lower than 9.0 I think .........it might be going way rich , and its not going to peg the MAF at say WOT at 3500 rpms , so dont worry about that ......you should have plenty of room and the tune should be real close anyway , get a new sensor and you should be good to go ...... Tim at MPH is an excellent tuner , you shouldnt need to touch it , if you do , just call him and he will advise you .......
 
#40
Is there a better replacement sensor I can get? I mean, if this thing is this fragile, I will replace one every six months at this rate. What Wideband do you guys run? I got the AEM because I heard from several people it was very accurate and cheap...

And if I fouled the sensor, do you think I fouled my 02s as well? I have an extra set of those :)

Ands its lean ---. it has the LEDs around the edge, and when it goes --- the leds are on the lean side.
 
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