Injector issues maybe?
 

My 97 kinda like backfires and blows white smoke when you free rev it. And it idles I Lil ruff.Is this an injector issue? Maybe something to do with the Hypermax? Haven't really heard much about the Hypermax chips. Any info would be appreciated and thank you

do you have access to a scanner?

Yes I do but not till next week my dad is out of town and it's at his shop.

Do a buzz test and cct

If you don't mind me asking what is a buzz test and a cct?? Thanks for the help

a buzz test is a test that you do with the engine off. it will put power to the injector which opens the cellinoid rapidly. it will uzz all 8 first, then each injector individually in numerical order. if a injector is bad it won't buzz and it will tell you which one. or is a injector is not that good, it will have a weak buzz. a CCT means cylinder contribution test. this will determine if there is a cylinder that isn't keeping up. when i run a CCT on mine, i get a #3& #8 balance fault. which is due to the CPS.

Buzz test will make sure the electrical side of the injector is getting power. Cct will ensure that the injector is working mechanically. Want the engine hot when you do the Cct though. Have you taken the hypermax off the truck to see if it still runs poorly?

Ok thanks guys. How do I go about doing these tests?? Sorry new to powerstrokes. And no I have not takin the Hypermax out yet it's a pain to get to cause its mounted behind my emergency brake pedal

Hey guys so I put the scanner on my truck and I have no codes did a cct test and buzz test checked out good. Also I pulled the Hypermax and still does the same stuff. Trucks lopes real bad when you first start it. My IPR was at 11% and my ICP is 580psi. Do these numbers sound rite??? Im stumped with this thing I just put a new fuel/lift pump on it. Thanks for the help guys

Nobody can help me out?? Had a guy tell me it could be the computer??? Any help appreciated thanks everyone