i have a 1993 z28 camaro been having issues like when the car sits for a while and cools down i drive down the road and when it get to an operating temp it will hesitate and stutter under acceleration i wont go anywhere only with 1/4 throttle will it move other than that it will sputter but will work fine in park and neutral u can rev it fine then but not under a load.
things ive checked
plugs and wires-fine
unplugged o2 sensors ran the same
changed fuel filter-which was very dirty and had muddy gas come out of it but after replacement problem preceded to happen
im gonna check the cat and mabey fuel pressure but i need ideas thank you

 

if your fuel filter was that dirty, it may have worked its way up to your injectors, clogging them.

 

just checked the cat with my temp gun and got no temp drop across the cat
and how can i check the injectors to se if there clogged

 

just checked fuel pressure and everthing checked out fine including the regulator

now wanting to check map sensor and tps sensor

 

u could also check ur coil or optispark

 

Under heavy acceleration I herd clogged EGR valves can cause this.

 

next time im checking the coil and for the EGR i stuck my finger on the plunger and pressed in while it was running and it seemed like the tone idle tone was changing

 

Think about parts that can heat soak - the IC module, coil, the optical cam position sensor in the Opti, the fuel pump. How did you verify fuel pressure? Did you test the pressure with the engine fully warmed up, on the road, at max RPM/engine load? How did you check the plug wires and coil wires? Did you run the engine in the dark and look for signs of arcing?

EGR is not used at WOT or above 3,500RPM.

Have you checked it for codes? And check the MAP sensor voltage. MAP reading is critical with your speed-density 93. Ditto with the intake air temp sensor. The coolant temp sensor in the water pump can cause problems with the engine as it warms up, if the ECM is not getting the correct temperature readings.

 

Also if you are loosing coolant,it's drippin down on the opti,causing this I think.My 02.

 

Try unplugging the EGR ,but plug the vacuum line to it. See if that helps.
IAC also a problem, on some, with tip in on the throttle.