Stalling problem '89 Olds Ciera, 2.8 engine

[Adamsmd]

Hello,
Seems I have an intermittent stalling problem on my Ciera. The symptoms are always consistant. The engine will start fine and idle ok. When the throttle is only slightly touched, whether in drive or park, the engine stops. You can restart every time but when you touch the the gas pedel, she dies. The problem doesn't seem heat related and is very intermittent. When the problem isn't present, the car's response and acceleration is great like nothing was ever wrong. I saw in another thread that a knock sensor could cause a false reading and simulate this same problem, but I'm not sure. Any help is appreciated. Mark..

[maxwedge]

Welcome to AF, have the fuel pressure tested for starters.

[f1040sche]

Does turning on the air conditioner help? This tells the car's computer to feed more gas. Read my reply dated 7/25/2007 on stalling problem due to the MAP sensor sticking. The MAP sensor is attached to the side of the air filter canister. It is used to measure air pressure and vaccum in the engine. When the car is stopped or slow rapidly, a vaccum is created in the engine. This vaccum will re-vaporize the droplets of gasoline lining the inside surface of the intake manifold and the engine, because the boiling point of the liquid gasoline is lowered in a vaccum. This extra gasoline vapor created is drawn into the cylinder to make the engine go faster just when the driver is trying to slow or stop the car. The computer of the car is program to compensate for this extra gasoline vapor by starving the engine of gasoline by slowing down the fuel injector while there is a vaccum detected by the MAP sensor. The fuel injector will spray a smaller amount of gasoline into the engine while the vaccum exist. Once the vaccum disappears, the computer stops starving the engine. However, if the MAP sensor is sticky, and sticks in the vaccum detected mode even after deceleration and stopping, the computer will keep feeding lessor amounts of gasoline into the engine. When you try to step on the gas paddle, the computer becomes confused thinking that it should feed even less gas into the engine to maintain the stopping process. This will stall the engine. After a while, the MAP can unstick, and the car will run like silk. If the sensor sticks on the highway, the engine can start to buck and hesitate and vibrate like the things are coming loose in the engine. In the previous post was mentioned cleaning out dirt from the very narrow slits that are clogged, inside of the air filter canister inside side wall where the MAP sensor attaches to the canister. If the car is very old, the service manual recommends new senors including oxygen and MAP sensors.