99 Alero 2.4 acceleration hesistation

[Kayla1774]

Hey everyone,

I have a 99 Alero, 2.4 that's been hesistating while accelerating. It only happens when I accelerate slowly at a low RPM, and doesn't happen when I give it the gas quickly from a stop. It has stalled a few times while driving at a slow rate of speed (under 30mph) and I also loose all power (steering, brakes) when this happens. It is also running rough at idle, but only when the engine is warm. It has a new fuel pump, new fuel filter, new spark plugs, and new coil packs, so what else could it be?!

[bulldawg19]

I have been having the same problem.

I have no idea what it is either. I was told it was my engine misfiring due to a faulty fuel gauge or my cat converter.

[Larson17]

Re-Check the gap on the spark plugs, unless you know for sure that you gapped them correctly in the first place. I say never trust what the box says (and most say not to mess with the gap because they're pre-gapped) because you have no idea what those plugs went through from getting packaged all the way to being shipped to the store. They get thrown onto trucks and dropped in back rooms so those gaps are probably not accurate.

I am assuming you replaced the spark plug wires, but I didn't see that in your list of replaced items, so if you haven't already, you should. If your wires are bad (because I had the same problem) it's going to run really rough, especially at low speeds or in gear when you're not moving (because you have a load on the engine).

If you have a ohm meter the rule of thumb for spark plug wires (I'm assuming it's a waste spark system...) is somewhere between 5,000 ohms - 10,000 ohms. I know it seems like a lot but you need a lot of resistance in those wires so your ignition module knows to push out a lot of voltage to jump the gap in your spark plugs.

Don't know if that helps you at all, but I'm headed to work, I'll see what else I can find out. :-)