HELP!!! Bog on acceleration, erratic idle!!

[ARTTII]

I have a 93 mass air EFI application on my Mustang. I have an erratic idle (surging up and down, engine shakes), and a big bog/delay/engine stumble on acceleration. If you hold it at a higher RPM the engine is smooth and does not missfire or shake... I have had everything apart and now got it back together, anbody got an idea what I should check first????

thanks

 

[HISSIN50]

PUll the codes to start.

On another thread, didnt you just attribute the issue to the temporary lack of lambda sensors?

Good luck and bump.

 

[Kdubslugga]

Sounds like maybe a vac leak/bad gasket. It would make sense if it clears up at higher rpm because the engine makes no vaccum at WOT