May be your care of the vehicle was lacking.....hmmmmm-

I had none of the issues you mentioned...now chevy's 2,8 was junk at best...

the worst problem I had with that car and motor was the distributer block off plate...the o-rings weren't very good on those motors and leaked as did the oil pan after I had about 100k on the ticker...

electrical-nothing
piston slap-nope
injector probs-uh-uh!

I use the best products-have for the 30 years of driving I have been doing...I always get good results with all my cars wheather they were Ford or not and I have had a ton o cars...lol