Fox HELP PLEASE Surging idle and then Stalls

[Luisr010]

need help my mustang is stalling.
It’s a 1987 ttop Mustang GT.
It starts and surges high for a second then low rpm bouncing until it dies.
So far what I’ve done:
Fuel pump, Fuel pump relay, Fuel tank, fuel filter,
Fuel pressure regulator, tfi module, egr valve.

Took off my intake to and inspected all the hoses.
I get 30 psi at the rail at the front.
I spray starter fluid after the maf a little bit and it
Evens out and runs nice. Then it stumbles and stalls again.
I’m all out of idea I need HELP please.

 

[mikestang63]

do the checklist in the sticky

 

[Luisr010]

it was running before fine I did go through the checklist but couldn’t find anything wrong

 

[Mustang5L5]

30 psi in what condition? Vacuum line off and plugged?

You should have 39-40psi. If only 30 you should investigate why it’s low.

Also, dump codes and perform vacuum leak/smoke test

 

[Luisr010]

I performed the smoke test multiple times no leaks either. And it shoots up to 40 psi then lowers to 30 psi this is while the key is in the on position

 

[Luisr010]

30 psi in what condition? Vacuum line off and plugged?

You should have 39-40psi. If only 30 you should investigate why it’s low.

Also, dump codes and perform vacuum leak/smoke test

In the ON position I get codes: 81o 82o 95o 81o 10o
With the car on while it surges i get codes: 21r 41r 91r 33r