I will try some idea's.
Have you run codes and what are they?
Do you have cat and it is not plugged?
No exhaust leaks near turbo, exhaust manifold and o2 sensor. This will mess with it.
Vam mounted and hose from it and turbo has no holes in it and spring in it?
Are you sure no vac leaks in intercooler piping? I had a bunch when done mine. IC Pipe Tester
Belt timing and engine timing correct?
Brand of plugs and wires?
Color and condition of plugs. Does all look rich or just one.
My ideas for now. Maurice
1989 Mustang 2.3 turbo, rebuilt SVO motor, 88 computer,vam upgrade, adjustable boost control, intercooler, c-4 trans
, 7.5 345 turbocoupe rearend, motorsport driveshaft, Black interior.
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