the swap went fine, but now it has a really bad miss, but it's not a miss so much as i think it's dumping in too much fuel, i've swapped out 3 different vam's, new motorcraft plugs, bosch wires, cap and rotor, fuel pressure sits 30psi idle and rises to around 50 psi when boosting, but it kinda pop's when revved boosting or not. all the while black rich smoke from the exhaust. i've listened to all the injectors with a stethescope and there all clicking. brown top #35 lb. what am i missing that would dump too much fuel in? i found the injector harness was wired different between the 2 cars. ( mustang and merkur) so i changet that and it got a bit better, but mot much.
i think it's dumping in too much fuel... all the while black rich smoke from the exhaust
Hey, if there's black smoke coming out the tail pipe, it means that the exhaust is rich in carbon. This means that yes, you have an incomplete combustion taking place which is a very low air:fuel mixture. You could be dumping too much gas in or you might not be giving it enough air.
what computer are you running? what engine i.e. from a 88 TC merkur etc. what size vam? and did you swap the brown tops from greens yourself or did it come that way?
pf3 ecm for merkur, small vam, turbocoupe engine with mustang harness repinned ecm #43 to vam sense, all other tied in under hood, timing belt was out one tooth, running better but still not right, i can take off each plug wire individually and it doesn't change at all.
Your fuel pressure is 30 at idle and rises to 50? Are you running 20 psi of boost? 30 is awful low. It should be near 40 with the vacuum unplugged. Did you lower it (assuming it's an adjustable regulator) because it is suspected of running rich?
The popping sound is definately from it running rich. Ask me how I know.
You might have an injector that is flat out leaking by and dumping too much fuel in a cylinder. What does fuel pressure do if you go KOEO for the pump to prime and then to key off? Does it stay solid for at least 10 minutes or so? If you loose pressure right away, pull the plugs and see if you have a wet cylinder.
I just re-read your other post. So you are running the PF3 EEC from the XR4Ti?
it's the smaller vam, we have both here, also changed bap,injectors,and pressure regulator which is stock non adjustable. with the vacuum line on i get about 35 psi, it goes up but the engine misses so much it's hard to get an accurate reading. i'd like to know why the engine doesn't change rpm no matter what spark plug wire you remove.
i screwed up, i tied into vpower instead of vref for the vam, wired it up properly runs awsome! thanx for your help guys!
Glad you fixed it.
I was going to ask if you wired it up correctly, but then I thought "no, it probably wouldn't even idle well"......I learned something, thanks!
turbo build problems, please help 
