Huge flat spot
 

Hi Guys. A newbie here and need help after testing many things.
My 98 BA 1.8 323 Astina developed a massive flat spot from idle up. It does rev up better over 2500 rpm but still has a small flat spot evident.

Its hard to start, slight throttle will get it revving up, but 10% throttle will just kill it.

Ive been to 2 mechanics and I am a former, but after testing outputs of TPS, AFM and fuel pressures which look fine, still no joy. Its got spark and Ive looked at the basics, but hoping someone has experienced this before and found a solution.

It must be something obvious as it happened instantly and the basics are all fine. Any ideas or specialist experience is appreciated. Thanks!

Possibly a cracked intake pipe.

And welcome to AGT :)

Hmmm... will have a good look. Would have to be a mighty big crack/leak to affect it that much but I hope youre right. Will let you know if its that. Thanks!

intake pipe, clean the throttle body, check your spark for any missing etc