amschnellsten

Hello I have an 86 944 turbo with an autothority maf. My problem is that I seem to be running extremely rich. During initial start up the car idles fine. After it reaches the first mark on the coolant guage I then have a wandering idle and stahling. Under partial throttle I have a stubbling effect which dumps black smoke out. The car seems to have no problem under full boost. I am running 15psi and my air fuel guage runs into the rich side. I have tried to adjust the small rheostat on the maf but it does not seem to have an effect. Any suggestions would be greatly appreciated. Would it help if I move the swith to a different position on the dme. I really love the performance gain and would hate to have to put it back to stock.

mark944turbo

Are you using autothority's chips? Adjusting the FQS switch on the DME will probably solve your problem. I am not sure which one autothority says to use, but I am sure somebody will chime in with the correct one.

amschnellsten

yes I am using their chips.

mark944turbo

Cool, IIRC the fqs on those 10-15% difference in fuel, so that could definately be your problem.

Peckster

Did it ever run properly, or is this a developing issue?

amschnellsten

it ran fine before the maf. any ideas?

cruise98

Have you checked to be sure the resistor is at 2k ohms? The adjustment screw is a rheostat that alters this value. The DME is looking for an air temperature value and this is the bandaid for that.

I forget which wires to check, but you should be able to figure it out from looking at it.

testarossa_td

What is the condition of your O2 sensor?

amschnellsten

I think My o2 sensor is crap.

pikey7

two things come to mind.

ISV? Idle OK when cold but dodgy when warm. Heard that before......

Try unplugging the 02 sensor to see if it's the cause. You should see no change in performance over the range if if it is bad.

TRWright

I have the autothority maf, and my car runs super rich since i installed it, it runs where it should be, until boost hits. No matter where the throttle position is, when the turbo spools, it goes rich. I tried to play with the adjustment as well, and the car will not idle if it is all the way left, so i have it where the car will just barely run, and that seems to keep it the least rich. When you figure this out, let me know.

Mongo

A friend of mine back was telling me how Autothority MAF kits have had several complaints and issues regarding rich condition and idles. Chances are these MAF kits are calibrated incorrectly causing the A/F ratios to be thrown out of balance. I've sseen one car at his shop where the MAF kit completely killed the car, fowled plugs and due to a sudden lean condition from 1000-3000 scorch the valves

Perhaps this may have been a bad batch of MAF kits that came out...

hmmm early Autothority MAF kits.....AMAF Kits. Makes sense

eman930

Sounds like tuning issues, Whay not drop Autothority a E-mail and see what they think

Mongo

Perhaps Autothority will do a warrantied repair and recalibration on the MAF sensor for you

testarossa_td

Mine runs rich as well, but cruising does fine for the most part.-ocassionaly on the richer side.(14.7-13.2)
Now after I have run some crazy power runs, it would stumble at idle.
On boost(14lbs) it is the top of whatever my narrowband reader will tell me.(12.3)
I found the problem was that the adjustment rheostat at the maf was actually vibrating and turning when I drove,so I tucked it into a better place, no problem since then.
Yes it is still a little rich, but nothing to kill a car.
I run Autothority Stage II chips with it, a Stock FPR and LBE.
Stock exhaust etc...
I tried a 3bar FPR but that was waaaay too rich, so until I upgrade some other stuff, it can sit in its box.
I tried using the instructions that came with the MAF but the car simply ran like garbage when I followed their instructions. I turn the **** until it wants to die then turn it the other direction until it runs a little higher rpm.