Hesitation in 98 Chevy Prizm

My 98 Chevy Prizm will occasionally hesitate when press on the accelerator. It usually happens after braking and then pressing on the accelerator. It seems to happen only after the engine is warmed up.

Any ideas on what is the problem?

I’m kicking it around in my head for a bit. The “after braking” has me asking for a more detailed description. Are you immediately going from the brake pedal applied to applying the gas pedal and experiencing the hesitation? If so, it sounds like a low manifold vacuum deal due to the brake booster actuation. Being a soon to be geezer, I find it a rather odd thing to immediately be applying the gas pedal after applying the brake pedal. I see some anxiety driven “traffic mania” type scenario. Now IF YOU MEAN “when I take my foot off of the brake from a stop, the engine hesitates” …that’s a different thing.

Assuming my proposed Mad Max driving method is being employed, I suggest that a brief pause be inserted into the event sequence. This should isolate vacuum as a cause here. That is, if indeed the brake booster vacuum assisted operation has anything to do with the problem, it would leave it time to recover. If no difference is noticed, then one can move on to other potential sources.

It is not a “Mad Max driving method.” The hesitation can happen any time after taking foot off accelerator for second or two and then returning to accelerator to maintain speed or accelerate.

Ah…that might be a MAP issue or a TPS issue. But you’re OBDII so one would think that if anything was too out of whack with either that it would throw a code.

Checked for codes on the OBDII. None present.

Then I’d look toward some EGR issue, if so equipped. If it’s a vacuum actuated valve, remove the hose and draw on it. If the idle goes to heck, it’s working fine. If you detect no change, then it needs servicing.

Before worrying about anything like mafs or egrs or stuff like that, how about you give a basic report on the state of maintenance on the car. If anything like spark plugs, wires, filters are even close to being due, then I would take care of that. A cleaning of the throttle body & MAF sensors while you replace the air filter wouldn’t hurt either.