a few months ago, i got inspired to get the missing link to replace the FCD in my hahn kit. i got it, installed it, and for some reason i got fuel cut right around the 0 psi mark going from vacuum to boost. i got annoyed with all of the "wild bucking" so i took the thing off and put the FCD back on. yes, i installed it the right direction (it's almost idiot proof), i tightened it up all the way, the gasket was there. i was pretty frustrated, so i took it off and blew one way through it and tried to go the other way but it wouldn't go through - exactly like it's suppose to work. i basically forgot about it until tonight when i was pretty bored so i started to work on it again.

same problem, again. i'm guessing that the valve isn't closing early enough, as if it's letting just the slightest bit of boost at the sensor but then when i have just a tad more boost it closes fully and doesn't let anything through. hmm. i tried to oil it tonight, but it still didn't really do anything, i keep getting fuel cut around 0 psi, but no higher and no lower. i'm pretty confused... does it require a "break-in" period? it shouldn't, it's a 1 way valve, what is there to be broken in? i don't really get it. any help is appreciated. anyways, i'm done now.

That is the same $hit that happened when I hooked mine up. Right now I have both it and the FCD on and it is running fine, not sure which to take off though. Anyone know why this is???

Mabe try and get a new replacement one if you can. Mine has never done that at all, and it goes into boost very smoothly, even at 0 psi. Never had a problem with the ML. I have had it for about 3 months or so..

I have mine for about 4 months now, I think. It's been working really good for me. I used to have the FCD, I took it off because it started to do that fuel cut.

How long after the install did the FCD go bad? Those that have both, have you experienced any problems?

shit I am with you too I have the missing link and I still get fuel cut... I am gonna put the fcd back on too to see if that helps... do you think that replacing the map sensor could help this as well?

I haven't yet remotely had any issues with the ML.

If some of you are having some issues, I would examine your voltage readings and your error codes. If the MAP values are staying under 4.7, then obviously the ML is doing its job. Moreover, if you haven't sprung a CEL because of it, then there might be something else as the root of your problems.

Again, the ML is only preventing your MAP sensor from detecting boost. If it's doing that, then a FCD isn't the answer. If you car isn't detecting boost and having fuel cuts, you may want to examine some things.

>you may want to examine some things

what sort of things would I start to examine?

I would look at the codes, and more specifically the voltage for the MAP sensor under boost.

If those things are normal, your fuel cutting may be attributed to somethign else, such as lack of (or too much) fuel or bad spark.

I had a bad MAP sensor a while back and thought that it was the FCD so I cliped the wires. I have been boosting about 7psi for a while now with no fuel cut. I have nothing but the MAP sensor, no ML or FCD. When I get my car back this week I am going to put in my injectors and boost 13psi, do you think I even need a ML? It is weird that I am using nothing and getting no problms.
Patrick
96 GS
HRC kit, S20G, FMIC, Howell bottom end 8.6 pistons, S-FMU, Blitz BOV, P&P head, SS valves, lots more little goodies