serious st... stut... stuttering p.. problem

when the engine's warm, between 2000 and 4000 RPM, occasionally the engine will stutter, like it can't make up its mind if it wants to be on or off.

chug a chug a chug a chug Vroooom

that kinda thing.
i thought it might be electrical, sooooo I bought new plugs, wires, cap, rotor, distributor, coil, etc, checked all grounds... no go.

next, i replaced the pcv and fuel filters.
then i checked the fuel pressure: steady 2 pounds. a little low, but it's steady when the engine stutters and when it's not.
then i checked voltage: steady 14.4 when not idling, 13.9-ish when it is.

i tried adjusting my A/F ratio a while ago, but the adjusting the screw didn't do a damn thing really. i just left it as far out as it could go cuz that seemed best......

is this an A/F problem? or what?

I would think so. Fuel/Carb related. Try some carb cleaner fuel treatment aswell as the spray down the carb stuff. Burn up all the gas in the tank before you add the treatment at the gas station with a refill. Give that a shot, and if it doesn't do a thing, maybe it's the low fuel pressure or in need of some carb adjustments or rebuild. But hopefully this does help.

It sounds to me like you might have a vacuum leak. Spray some carb cleaner on the vacuum hoses and around the carb and if you hear the rpms change then you have a vacuum leak. If it does have a leak try and find it better with more carb spray to locate the leak. The replace the correct parts.

-Mike


edit: didn't see your fuel pressure was that low, looks like you need a new fuel pump.

2psi, that is low. you need a new fuel pump.
it can be that it is not filling up the fuel bowl fast enough.

i will check the vacuum hoses tomorrow and see what's up with that...

as far as fuel pressure goes though, do you think it could be that? as soon as the engine get's over 4K it's good to go, floored or not. also, it only does this some of the time, not all the time. and the pressure is steady...
i just got a new fuel pump about 6 months ago. the car felt like it was just losing power all of a sudden, but it wasn't stuttering, it would just lose power, and then magically pick it back up again (if i was lucky).

Check your booster venturies https://www.3geez.com/showthread.php?t=8972

dang! lotta info there. thanks alot

my dads toyota did that until he adjusted the valves and timing, now it runs faster and better!

My carbed Accord did something simular to that. Mine would act up only after warmed up. Idled fine and under hard throttle but that 2000-3800 cruising range it hesitated. Near drove me crazy. Took me a while to figure it out. Honda mechanics I spoke to couldn't figure it out. I had to energize my solenoid fuel shot-off on back of carb. I just ran a fused wire from accessory connector (one that is powered only with ignition on) in fuse box through fire wall to solenoid using a quick connect. That was my problem. $2.00 in parts. Good luck.