hi
im having a strange problem with my 440 in my duster in the warm-hot weather. after a long drive if i do a full throttle pull for more than 6 seconds, at 7 seconds it will sundelly starve for fuel to the point the car stops accelrating. once you let off the throttle its rins fine until you do a nother full throttle assult.

here is the catch. if the car isn't driven for a long time(less than 25 min) its fine. only after a long drive it acts up.

i also have recently run the car out of gas and then i changed the fuel filter to try to fix the problem with no sucess.

never had this problem befor with the same setup

also at idle the fuel filter is almost empty when hot but 3/4 full on a cold start @ the same 600 rpm.

please help!

Thanks
Nick

If you can, rig a small can of gas in the eng compartment connected to the pump inlet & take her out. that'll take the tank/sending units/sock/rear line out of the equation. Still acting up?, pull the pump/pushrod (pushrod should be 3&1/4" iirc)

So the whole problem started after you ran out of gas? Sounds like you sucked up some crap from the tank.

sounds to me like the fuel pump is getting weak.

what happend is i changed the carbrautor because the old one had a bent throttle shaft. after that i was running the car in the greage for a while to tune in the idle and mixtere. as i was leting it run it ran out of gas. i put gas in it and then took it for a ride. it was a cold night and it ran great. that was a week ago. today i drove it and it was 75 degees out. after a long drive it acted up. the longer/hoter it got the worse it got. it starts as only doing it after a long pull. to doing it after a short pull.

i dont think its the carb because it seems to be heat related. but why would it sundelly have a problem?

it had No problomes before like this.

it has no problems in cooler weather.

last year the car ran fine in even 100 degree heat.

Just a shot in the dark here but, try it without the gas cap. The one way valve in those goes bad, occasionally. Since it happens only after a period of time of running, you could be slowly building up a vacuum in the tank with the pump pulling. It's easy & costs nothing to try it, anyway. If not, then I'd suspect the sock or the pump.

looks like i have some things to try tommorow. think it could be vapor lock. i can see little air bubbles moving around the fuel pump when the cars shut off?

the bubbles are in the fuel filter

my sb would blow bubbles in the filter and do the same thing

I swaped a new pump on and fixed it for a while,then the bubbles would come back in 5-6 weeks of daily driving

swaped 5-6 pumps before I found it sucking rust into the pump and rupturing the diaphram

also found pin holes in the 68 steel line at the back by tank too

new line and one more new pump with filter before the pump fixed it

I removed the line and did not see any holes or wet spots.. but lots of rust/scale

slaped it down on the concret and there they are,I could see them after the rust got knocked of

check gas cap like said also

Had the same problem with my 440 and the problem was the fuel pump rod had wore off about .250 put a new mopar one in and been running good ever since.Buy a good one not a cheapo as the cheapo's are not hardened as good as the quality one's like from chrysler.