Subaru engine sluggish in first gear

SOURCE: Cold Start Idle Issue

Problem might be the air control valve, it's located at the right side rear of intake manifold and has a hose going to the air intake duct from the air cleaner, as a test you might try pinching off that hose when the idle is a problem.

SOURCE: 2000 ford explorer 4.0 x-engine is stalling, missing and lose power while driving

I personally would check the fuel pressure. Then I would go back to the coil. I have seen brand new bad coils out of the box. The symptoms of a loss of power point to this component, especially if the car idles well, but loses power when accelerating. Please do not rate this reply - we all are left to grasp at straws since you have changed pretty much everything. Good Luck. Please post the final fix of the problem.

SOURCE: '99 chevy Silverado Z71,5.3 engine.....will not rev when hot.....

try replacing your EGR Valve, or your Oxygen Sensor

SOURCE: 1992 gmc chevy 350 wont idle when warm

This could be a number of things but i think that your problem sounds like a vacuum leak or an EGR problem. Try listening for leaks and try un-plugging the EGR solenoid valve one time.

SOURCE: intermittant stalls & rough idle

You might have leaking injector(s) or injector O-ring(s). It could be leaking inside the fuel rail feeding fuel constantly. The pressure could be OK because the computer compensates by working the fuel pump harder in order to keep pressure within specs. I have a similar problem in my 99 Outback, it rough idles at stops intermittently. I recreated the problem, I checked it in my back yard, turned it on, let it warm up. Then I put it in gear went forward stopping and going with the e-brake until it rough idled. I got out put some bricks in front of the tires and started checking around. I noticed when it rough idles the transmission makes a constant sound. I would describe it as a fast ticking, sounds electronic. I tried messing with the idle by adjusting the TPS. I noticed that when I set the TPS to where there was little or no signal coming from it the sound would stop and the idle would be normal. I haven't had time to check it again but I don't know what to think of it.