Initial Tweec's and Problems...

Joes95GT

New Member
Jan 23, 2003
3,132
1
0
Delaware
This little thing is pretty cool. Too bad I don't understand most of it...

I started off by switching to the J4J1 calibration and immediately, just from the calibration switch alone, it idled without stalling. I changed the fan speeds, added 6 more degrees of spark (with the base set at 10* on the balancer; 16 total base), and set the MAF minimum voltage to 0.01 and maximum set to 4.99x. Unfortunately, my battery is smoked on my laptop, so I can't do any more dataloging than at idle. I have to have the laptop plugged in at all times, so datalogging is limited. I did notice that the car DRINKS gas. I haven't even got on it and I've used more than a half a tank in 65 miles.

This is where it starts to get weird...

The car runs so fat at idle, the fumes burn your eyes. However, when I checked out the LAMBSE and KAMRF, they told me the car was lean. WTF.

LAMBSE 1 - ~11.5
LAMBSE 2 - ~13.0
KAMRF 1 - 1.000
KAMRF 2 - 1.102

I'm assuming 1 and 2 are the banks? I have no clue why there is such a difference between the first set of values and the second.

At idle, I didn't think the TPS should be more than .99 V, but it hung steady at 1.044 volts. Throttle screw backed too far out?

The MAF was flowing a steady 0.9x kg/hr and the injector PW fluctuated between 3.2 and 3.6.

My question is why is the car running so rich, but the LAMBSE and KAMRF say it's lean? Even with the car backed out of the garage and into the driveway, it still burns your eyes. You can visibly see the raw fuel coming out of the tailpipes. But the computer says it's lean?

Also, is there a way I can turn back fuel pressure at idle with the Tweecer or do I need to install the adjustable regulator. I have one, I just don't feel like putting it on if I don't have to. :D

Thanks for any help.

Joe
 
LAMBSE is the instantaneous target A/F -- so 11.5 and 13.0 mean the EEC is trying to achieve 11.5 and 13.0 respectively. It is basically useless for tuning, because it's just the instant target right now, it has nothing to do with long term.

KAMRF is fuel trim -- 1.102 means the EEC has learned that it needs to add 10.2% fuel on that bank at the given RPM & load to achieve stoich.

I would start by making sure your injector scalars are correct, as well as your MAF curve. What MAF do you have? Anytime KAMRF is out of whack, the first place I look is MAF. Odd, though, that you are only seeing symptoms on one bank. O2's okay?

Dave
 
HairyCanary said:
LAMBSE is the instantaneous target A/F -- so 11.5 and 13.0 mean the EEC is trying to achieve 11.5 and 13.0 respectively. It is basically useless for tuning, because it's just the instant target right now, it has nothing to do with long term.

KAMRF is fuel trim -- 1.102 means the EEC has learned that it needs to add 10.2% fuel on that bank at the given RPM & load to achieve stoich.

I would start by making sure your injector scalars are correct, as well as your MAF curve. What MAF do you have? Anytime KAMRF is out of whack, the first place I look is MAF. Odd, though, that you are only seeing symptoms on one bank. O2's okay?

Dave
Yep Dave, the O2's were fine, both were switching, and seemed to be acting the same as far as voltage goes. I have a 76mm C&L MAF with the 24 lb/hr calibration tube. The injector scalars are whatever is programed into the stock J4J1 calibration. I haven't touched them. Since C&L doesn't give a MAF function (flow sheet) with their meter, I'm not sure if I can alter the low end of the curve without having any certain values.

Joe
 
As a soon to be new tweecer, From the month of reading I have been doing, for a starter GET EEC ANALIZER!, it seems to help get your inj. pw or dc at a good base, as well as map the MAF, I too am using a C&L (73mm and 24#) and there seems to be no drop down menu for them like the ProM. From what I have read the analizer can give you a very good chart on the MAF.

I might be wrong here as I have only "reading" knowledge as of this time but arn't the PW supposed to be less than 3.6-3.2? for some reason I am thinking I saw 2ish as the number or something (mabee 1.9).

Also you might get more help on http://tweecer.oplnk.net .

There is a good link that is on www.tweecer.com that brings you here to a faq on tweecer terms and settings very informative but I dond know were it is without the link :shrug:
 
Joes95GT said:
I have a 76mm C&L MAF with the 24 lb/hr calibration tube. The injector scalars are whatever is programed into the stock J4J1 calibration.
What color tube? On a GT, 24# injectors would use the black tube, but on a Cobra would use the stock tube (says '.650' tube, maybe it doesn't have a color).

http://www.cnlperformance.com/calibration.html

Remember that since the Cobra has 24# injectors stock, and the GT has 19# injectors stock, but they both use the same MAF -- the faked "calibration" from C&L has to be for the right EEC. If you have a C&L meter calibrated for a GT, you can probably get away with changing the injector scalars to 19# on the J4J1 calibration. Optimally you want the actual MAF curve for that meter with that calibration tube installed, so that you can plug it in correctly. C&L doesn't think you need this information, however, good luck on getting it out of them...

Dave
 
HairyCanary said:
What color tube? On a GT, 24# injectors would use the black tube, but on a Cobra would use the stock tube (says '.650' tube, maybe it doesn't have a color).

http://www.cnlperformance.com/calibration.html

Remember that since the Cobra has 24# injectors stock, and the GT has 19# injectors stock, but they both use the same MAF -- the faked "calibration" from C&L has to be for the right EEC. If you have a C&L meter calibrated for a GT, you can probably get away with changing the injector scalars to 19# on the J4J1 calibration. Optimally you want the actual MAF curve for that meter with that calibration tube installed, so that you can plug it in correctly. C&L doesn't think you need this information, however, good luck on getting it out of them...

Dave
So you're telling me I'd be better off switching the sampling tube back to stock? I still have the stock .650 tube. The tube I'm currently running is the black tube for GT 24's. I didn't even think about the calibration differences...

Joe
 
Joes95GT said:
So you're telling me I'd be better off switching the sampling tube back to stock?
Yep. The C&L is trying to fool a GT computer, and when combined with a Cobra calibration it's making the EEC calculate fuel delivery based on 19# injectors. No wonder you're running rich :D.

Dave
 
I've got to give it to you guys again. I think you found my (stupid) mistake. :D

Once the motor got warmed up and into closed loop the LAMBSE was 14.7 and the KAMRF was slowly dropping from a 1.2xx. It smelled much cleaner. I posted previously that bank 1 was much different from bank 2; that seemed to be a thing of the past as well.

One thing I still haven't found definite answers on are my TPS voltage.

TPS voltage varied slightly between 1.04x and 1.05x. That's a bit high, but I assume it's not hurting much? I'm just curious as to why it's not at the normal 0.97 - 0.99?

Sorry for all the questions. I've searched both Stangtuning and Tweecer and it seems that the people are more advanced than I am. I'm trying to learn the little stuff by reading the big stuff. :bang:

Joe
 
Joes95GT said:
TPS voltage varied slightly between 1.04x and 1.05x. That's a bit high, but I assume it's not hurting much? I'm just curious as to why it's not at the normal 0.97 - 0.99?
I usually see 0.94 on mine :shrug:. I don't really worry about it, the EEC should baseline its measurements at whatever the voltage is and work from there. If you have doubts, then put together a payload that includes both TPS voltage and throttle position. Then you can see how the EEC is interpreting the voltage. If it drives normally, and the throttle position correcly registers as closed, part, and wot, then I think you're fine.

Dave