rough thottle response

[mesman]

i bought a 1990 d250,318,4spd.someone desmoged this rig.air cleaner assemby is gone.they put a holly(about 9"X4") air cleaner.smog pump is still there,just not hooked up.on the front of the throttle body the bottom vac port has been plugged. sometimes when i take off from a stop it spits and sputters under hard throttle.when i take off easy and slow it runs better,but sometimes seems like it still has a miss.anybody got any ideas or info about this truck and that airpump?

[Speed Dragon]

have you done a tune up and checked the timing yet?

[onedeafnote]

i've got the same problem, with the same stuff...i checked and rechecked my timing, and have even tried timing it to where it will idle better and respond better.....i can rev the heck outta the truck when in park or neutral, but whenever i stomp on it the thing bogs down and almost dies....i got a tip from a friend to check out the kick down cable though...anyone got any idea how to tune of a holley 2 bbl??

[mesman]

ya, mines efi throttle body.im thinking ignition though with mine because it backfires out the right bank exhaust once and a while.when it warms up here im gonna start messen with it.

[Speed Dragon]

ya, mines efi throttle body.im thinking ignition though with mine because it backfires out the right bank exhaust once and a while.when it warms up here im gonna start messen with it.

you could have a worn rocker arm.

[Speed Dragon]

i've got the same problem, with the same stuff...i checked and rechecked my timing, and have even tried timing it to where it will idle better and respond better.....i can rev the heck outta the truck when in park or neutral, but whenever i stomp on it the thing bogs down and almost dies....i got a tip from a friend to check out the kick down cable though...

check the accelerator pump

anyone got any idea how to tune of a holley 2 bbl??

yeah, throw i away and replace it with a carter :D

[bjsstang03]

holleys not a bad carberator, i like it. there intakes are sweet.

[onedeafnote]

yeah, throw i away and replace it with a carter :D

haha....im havin nothin but troubles with this holley...i might just take the damn thing off and toss it. Its got so many connections and stupid wires hangin of the thing, but i switched intake manifolds and none of em connect to anything.... :help:

[MacBP89]

I have an 89 D100 318 tbi automatic. I was having the same problems. Ended up being a plugged catalytic converter. Hollowed it out and shes running like a champ.

[jbgarrido]

I did the same thing, disconnect air pump and air chamber and lines located at lower body of carb also plugged up line at converter. Had good response for a short period of time then engine started to blog-down. Spark plugs, oxygen sensor and air chamber carboned up. Long story short, I reinstalled the air pump, reactivated the associated air lines and replaced the converter with a straight pipe. Back to normal with better response without the converter. Getting approximately 20 miles per gallon gas with the 318 engine.