94 d21 miss at idle and cruising speed

[bcp385]

I picked up a 94 Hardbody the other day. great little truck, runs like a top! Truck does have a slight miss at idle and cruising speed, like 60 mph on a flat road barely giving it any pedal. If I mash the accelerator any pass that it runs great. No hesitation, no lag. Only issue is at idle and cruising speed. Does not matter if your doing 30 mph or 70 mph, as long as your toe is just pushing the pedal a little, it is there. I replaced the wires, new NGK plugs, new cap, and rotor button. Any help would be greatly appreciated.

[macgiver]

mac, vacuum leaks usually diminish/ disappear at Wide Open Throttle ,yet ARE present just where you say -idle and at a "featherlight" cruise.

[bcp385]

Have checked all hoses, visually and by spraying carb cleaner over all of them. No change... I tried some of the Sea Foam cleaner that sprays directly into throttle body. No change... I am wondering if the timing could be off a little. Thoughts???

[macgiver]

mac, I'm sure you mean "base" spark -timing.Yes ,something to check , and keep in mind - too advanced is easily recognized by easily detectable "pinging" under med. speed(45mph) and steadily climbing acceleration.

[bcp385]

Thanks, It is sometimes hard to start if it is warm, only been off a few minutes to 20 minutes or so. That makes me think timing as well.

[bcp385]

I tried adjusting the timing this afternoon, no change in the miss. Guess it could be a valve???