i have a 97 z28 with the 5.7. i just replaced the intake gaskets becaust the rear seal was leaking oil down the back of themotor, i also replaced the valve cover gaskets while i was there, when i put the motor back together i picked up a nasty miss on 1 and 3, i removed the fuel rail and saw that those injectors were not spraying, so i replaced them with brand new GM units, now the injectors spray like mad but still have a miss on those cylinders, i pulled the plugs to check for spark and they both had good spark, i checked and double checked the vacume lines to see if i missed one, they were all good. i have a snap on solus pro scanner and i can count missfires and the only 2 are 1 and 3, any help would be great thanks.

the car is completly stock and the customer is getting pissed to keep comming back to the shop. the car ran good except for the oil leak b4 i took it appart, what is doing this

 

Do a leak down test to see if there is burned (valve or piston) problem in those 2 cylinders. If it was running lean for a while, no telling what could have happened.

 

i was trying some stuff to fix it and removed the tps sensor plug and the misfires stoped, what could be causing it, on the scanner the tps works but when its pluged in it misses. if u unplug the sensor while its running and then plug it in it stops missing but once you turn the car off and restart it the miss comes back

 

any ideas??