so bought a 95 blazer 4.3 vortec auto tranny fully loaded last week ran like a raped ape then the check engine light came on got it scanned and there were misfires on multiple cylinders tps and map sensor codes came up and when the cap was replaced the screws broke and the cap is being held down with a zip tie gonna fix that this week
recently replaced
tps
iac
map
cps
cap rotor plugs wires
fuel pump
fuel filter
fuel pressure regulator
o2 sensor
new cat converter
and has 175 and change on the clock
please help i cannot figure this one out

 

It would help if there was a timeline. Did you replace all that stuff afterward, or what?
I think you spent a LOT of money on stuff that wasnt broke.
First rule of car forums: we want codes, not what someone thinks they mean.

 

ok thank you for the quick reply i cant tell you the codes cuz the guy at advance auto didnt give em to me and all the stuff replaced was by the previous owner within the past 2 years the only money ive put into it was a fuel filter i have verified the map and tps are good by un plugging them one at a time and the engine either dies or runs really rough and to add the symptoms only get really noticable when the engine reaches operating temperature

 

Insist on codes. If they wont give them to you, ask for the mgr. If he wont, take your business elsewhere.
What you verified is that they kinda work. Unplugging to check how well they work only works with the MAF and you dont have one.

First let's deal with missfires... do you have problems starting engine at any time. If so when and under what conditions.
More when damp or wet is a big clue
You need new cap and rotor at the least.. make sure it's AC Delco.. {or Delphi if that line is carried} Both those brands do GM OE engineering and you can only count on them. remember that for other parts esp fuel pumps.

And wires. bad wires usually results in specific cylinder missfires but you shouldnt count anything out. Cheap plug wires OFTEN are bad when new right out of the box. If not AC Delco then Belden 8 mm.
Also a possibility is the coil but do cap/rotor first and make sure the little vents at base of dist are clear.

You also need to do a fuel pressure / leakdown test.

 

Fuel pressure/leakdown test was performed and it was all good and ill be replacing the parts soon and then report back my results.