I just replaced the MFI spyder injection due to rough idle, misfires and poor acceleration and mileage. I had previously changed the distributor for a P0300 DTC. Fuel tank and pump/sender brand new also. Problem still there but no DTC's reported to scan tool. Any further suggestions?

 

whats the fuel pressure at key on?

Hopefully you didnt buy a aftermarket pump. I gave up on em after finding so many of them dead out of the box,or weak.

 

60 psi after air was bled from system. Today, I cleaned the MAF sensor, it was contaminated with oil and changed the ETC as this problem seems to only arise after the vehicle warms up and enters the closed loop operation.

 

I am almost ready to spring for a new catalytic converter as this seems to be a temperature issue.

 

o2 sensor maybe. They dont kick in till temp is up also

 

x2 on an O2 sensor. MAF? Leak in the air intake between MAF and engine?