always running rich with gm maft/safc combo

[dnhieu]

okay here is the deal, IM ALWAYS RUNNING RICH! my low and mid are okay at or around 100% but my highs are at like 82%. i did a wot pull the other day and my o2 voltage are at .84 which means im lean since i have a 1g. i know i shouldnt use o2 voltage to tune but it does give me a general idea where im at. no matter how much fuel i take out my high never seems to change. also if i say step from 650cc injectors to 660cc injectors on the maft what kind of percentage of fuel am i taking out? my high knob is on its fullest lean and i need to take away more fuel across the rpm band so i can free up some more clicks on it.

also i have herd from alot of other people locally that they had problems with always running rich with there gm maft so they switched to a chiped ecu and 2g mass and it seems to have cured the problem up. is anyone else have the same problem? i know every day i come out and my fuel trims are always moving and they were experiencing the same problems before they switched. i just dont understand....


thanks
david

 

[GVR4592]

My O2's always read around .82-.84 at wot on the narrowband and high 10's on the wideband. So I wouldn't base any of your assumptions on the narrowband. If you can live without the MAFT, then ditch it. There isn't a huge adavantage to having it with your mods. It's much easier to tune a stock maf sensor.

 

[dnhieu]

My O2's always read around .82-.84 at wot on the narrowband and high 10's on the wideband. So I wouldn't base any of your assumptions on the narrowband. If you can live without the MAFT, then ditch it. There isn't a huge adavantage to having it with your mods. It's much easier to tune a stock maf sensor.

the thing i dont understand is that there are so many people that run fast using the MAFT but everyone i have ever seen hated it and got rid of it. but does anyone else have problems with running rich and there fuel trims always outta wack? i mean i go to bed and my trims will be at like 104% then i wake up and its like 89%....


thanks in advance
david

 

[tstkl]

yea, a lot of people have problems with them. I dunno who your talking about that run fast time with mafts, but Im personally just going to go dsmlink or aem ems as soon as possible, so thats that. My trims don't change overnight though... dunno what your talking about...

 

[GVR4592]

There are some guys on the dsmlink forums that run pretty quick times, but they also say that without dsmlink they would never get the maft dialed in properly. I put it on my car for a day, I didn't notice anything that could be considered a performance gain. Spool time was the same, driveability was the same, power was the same.

 

[dnhieu]

thanks guys for your input. well one person that rings a bell is devil sperm that has a good track time with the MAFT. i have also herd and seen people with smaller turbos having good success with it. i know before my buddie switched his setup from a 14b to a 60trim he was running like a 12.3 then only put down a 12.1 with the 60 trim untill he said screw it and got rid of it and burned a new chip. this was only one person tho so i was checking on here to make sure others were having the same problems.

thanks again
david

 

[madman]

okay here is the deal, IM ALWAYS RUNNING RICH! my low and mid are okay at or around 100% but my highs are at like 82%. i did a wot pull the other day and my o2 voltage are at .84 which means im lean since i have a 1g. i know i shouldnt use o2 voltage to tune but it does give me a general idea where im at. no matter how much fuel i take out my high never seems to change. also if i say step from 650cc injectors to 660cc injectors on the maft what kind of percentage of fuel am i taking out? my high knob is on its fullest lean and i need to take away more fuel across the rpm band so i can free up some more clicks on it.....
thanks
david

How high are you highs? 4.5k 5k 6k or 7k

Really, I don't even look at my fuel trims above 4.5k becuase I'm never crusing above that and If I do get above 4.5 I'm most likely in open loop so the trims arn't even being used.

But I can keep my trims pretty consistant over the last month, that's all the time I've had it installed.

I think I'm way off on my AUX and BASE settings though because I'm having to add a lot of % in lo for 1k......long story I just haven't corrected it yet.....but still the trims hold consistant and I' have no problem leaning the car out or adding fuel if necessary with my AFC.

Do you think there might be something wrong with the actuall GM MAF sensor?

Is the sensor clocked the right way in the car?