1990 f350 did not have a turbo, unless it was fitted after market, so check what engine you have such as year and size and then maybe we can answer your question
how do i down load a wiring diagram for a f350 6.0 diesel engine compartment
yes all powerstroke engines are turbo
4 million pounds
blow by through the turbo ,my truck did the same thing had to get the turbo rebuilt
mercon sp
my 93 f350 turbo diesel was 190 hp stock , but by putting a banks sidewinder turbo , cold air intake , k&n air filter , and straight piping it , it is well over 300 hp , howeaver my dads 2005 f350 is stock 325 hp
clogged or damaged catalytic converter
A fuel filter
How do you change the alternator on a 1996 ford F350 diesel
it can be unburned fuel damaged turbo charger etc. light amount of smoke can be normal large amounts = problem.
where does the oil pressure regulator on a ford f350 diesel truck
According to the AutoZone website : For a 1995 Ford F-350 , 7.3 liter turbo diesel engine : With engine oil filter change : ( 13.9 U.S. quarts )