I just got my ML in yesterday, I took off the supplied FCD from Star. It worked fine, but I just didn't trust it. I put the ML on and within 5 minutes of idling the car is putting out solid black smoke. I take the spark plugs out and sure enough they are solid black. It didn't run that rich with the black box but it is now. My fuel setup consists of the 12:1 FMU and Walbro fuel pump supplied by STAR. Anybody ever have this problem?

at idle it doesn't matter about the fuel. The fmu doesn't come into play until the manifold pressure is above atmospheric.

All the ML does is prevent the MAP from seeing voltage above 4.7 Volts so I dont' know aht the probelm is. Maybe someone else does cause I have a 95' and have never had to deal with fuel cut. :shrug

I have had this problem before too.

Does your ML use a little filter on the side of it? If it does, make sure it didnt pop out, or possibly clean it. You can also clean the whole ML with soap and water. If that doesnt work, go back to the FCD or build your own FCD.

Also might want to recheck your connections in your MAP wiring since you had one of those wires cut when using the FCD from Star.

i have the same fuel mods as you with the hahn set up and my car ran rich as hell for a while at first but seems to be pretty normal now.

Originally posted by eclipse982nrRST
I have had this problem before too. Does your ML use a little filter on the side of it? If it does, make sure it didnt pop out, or possibly clean it. You can also clean the whole ML with soap and water. If that doesnt work, go back to the FCD or build your own FCD. Also might want to recheck your connections in your MAP wiring since you had one of those wires cut when using the FCD from Star.

Yea it has the filter on the side...for some reason I started it up and like 5 minutes later it was dirty. I cleaned it off and flipped the ML around where the filter doesn't face the intake manifold and its been doing fine, so far so good

my filter is facing in towards the manifold also and i get problems occasionally

i think i will spin mine around as well and see what happens