87 chevy EFI issue

[Tjerica1201]

Sometimes itll start with a little bit of throttle and be fine (after throttle is released). Sometimes it'll die a short time after the throttle is realeased. Sometimes it'll stay running if I keep a little bit of throttle...sometimes it doesn't. In attempting to start checking off the basics, I'm installing a fuel press gauge (setup from RV Morse) to make sure fuel press isn't dropping off for some reason. My question at the moment...I've disconnected both fuel lines at the throttle body and turned the key to prime the fuel lines and am getting fuel flowing out both the pressure and the return lines. This doesn't seem normal to me. What do you guys think?

If you guys have any advice on what to check after I've checked fuel and spark let me know.

A little bit about about the truck:
mild build 383
670cfm holly throttle body
bored endlebrock intake
Full msd system
stans Tri-y headers
EGR delete
tuned by old school efi

Thomas

[VileZambonie]

Stock in tank fuel pump? Get the actual fuel pressure readings with everything hooked up. Ensure timing is set, check for vacuum leaks, check min IAC setting. Do you have the factory prom still?

[Tjerica1201]

-Ive replaced the pumps with a higher pressure pumps
-When the truck starts it runs perfect (except for needing throttle position) so I do not think it's timing, but I'll put it on the list of things to check
-No vacuumed leaks (that I can find)
-min IAC setting? can you elaborate?
-custom live tuned by old school efi