My 97 bonniville starts but then stalls right away

Have you checked the fuel pump for any blockage? The car isnt getting any gas unless u manually pump it by pressing the pedal.. So start there
Sometimes when a engine requires excessive revving and throttle to stay afloat its a fuel supply problem. A clogged filter for example can be overcome with excessive throttle that drives the fuel pressure up enough to force it through, but it will barely trickle at idle and stall.

Usually the dead give away for fuel pump is when someone complains they have to floor it as soon as it turns over or it will die right away.

How many miles on the car?

Most in-line fuel filters are good for about 100 miles.

Then,crud buildup blocks fuel passage,causing the car to stall.

Tbe,, after fuel presure drops off,the crud falls away & the car will start/run.

Repeat same,until you get crazy.

Replace the cilter,problem goes away.

God luck.

how to remove vectra 1.9ctd fuel injectors

Crankshaft and or camshaft position sensors are marginal. If they go out, you won't runs at all.

You need to retrieve the BCM (Body Control Module) faulty code with a scanner. Fix any code that you find.
Try to erase any code and see if the problem is solved.

Hope it helps.

car idles rough and stalls when driving wont stay running

I would start with checking the fuel filter. After taking it off try blowing through it. Should be very little resistance.

The Computer for this year is normally set to go to base mode if the computer fails, base mode means you get 1,3 and reverse gears and the gas mileage is bad, this is so that it don't leave you stranded. If it;s slow to start then most likely it is the fuel pump and filter are needing replaced that will cause the car to not start up right away. Also the other problemscould be related to a simple fix for al of them and that is dirty battery or low battery voltage or altanator output is low. You can take to most parts store and have the Battery and altanator tested for free.

could be or maybe a bad fuel pump

heater core may be going bad...things to check.. heater core, thermostat, anti-freeze/coolant, wires to the heater.