I have recently began having issues with my 86 IROC again this time another fuel starvation problem. It began a few days ago with my Holley 4160 (1850-4) I could stomp it and all and it drove fine then one day on the way to work when i was cruising (very light throttle) at highway speed (65-75 mph) it sputtered and surged then it went lean slowed down as i gradually tried to accelerate then stall on the side of the freeway. This is with 3/4 full tank of gas. Couldn't get it to start then so my buddy drove me the rest of the way to work that morning. Around 3:00 we went to get the car sprayed some starter fluid in and drove it home but at part and 1/4 throttle it bogged and ran lean but past that it ran fine. His dad and I thought carbuerator so we put a 78 rochester quadrajet he had on it and i ran perfect nice smooth low idle and good throttle response best my 305 has ever ran. So yesterday morning i felt it was safe to take it to work and again on the interstate it stalls again. Let sit for 30 mins sprayed some starter fluid and fired it up and drove good but this time i stayed off the highway finishing my trip to work with my average speed around 40 mph but it stalled once more before i finally got to work. This time when it stalled there was no gas in my clear filter I thought fuel pump so I go to change it after work before going home. Put a new mechanical pump drove it 10 miles and it stalled the same exact way again but this seems to be a problem only when warm due to how long it takes before Im stalled again but once it happens it's does it frequently.

 

have you changed the fuel filter under the car? try leaving your gas cap loose if you have a non-vented cap. just tossing out a few ideas.

 

Are the non vented caps the ones you have to unlock with a key?

 

locking caps come in both designs. next time your car stalls, unloosen the cap,...do you hear a swoosh sound?

 

yeah i heard a hiss when i took off the cap since you've mentioned it i drove around a little yesterday and took it to work this morning with the cap half opened maybe it was a venting problem (i dont understand how) because now it doesnt stall and drives better now i notice that i have a slight fuel leak around the choke\ fast idle cam area (at least that's what I think it is this is a `78 750 rochester quadrajet) and hard starting and brief rough idle when warm.

 

do you have a fuel return line?

 

Sorry for waiting so long to reply been working...anyways both my new factory pump and carb have a hook up for a return and both are blocked off I have no hoses to them

 

glad to hear its running better. without a vent, its kinda like sucking on a straw while your finger is over the other end.

 

yeah it was a PITA going to work in the morning and ending up on the side of the highway 2 to 4 exits away and being late when it finally decides to starts and running the same excuse to bossman. But could the fact of me not having a charcoal canister be the reason that it stalled in the first place?