IT is doubtful that all of those sensors are hosed up. However, there may be one of those that is contributing to the problem.

First, reset the codes and then run it again, and see if you duplicate the code readings.

The MAP (Manifold Absolute Pressure) sensor is a GM part, and is easily replaced. If the MAP sensor goes bad, it can cause a host of maladies, from rough, rich running, to very lean conditions. It depends on what the failure of the sensor is. However, they really don't fail that much, and from what I've seen, most of the replacements aren't necessary.

There is a diagnostic mode that you can put the car into, to test the idle air control valve. It actually cycles the valve so that you can hear it. You should also use the function that fires the fuel injectors, to see if that is working properly as well. Each of these tests can help you--even by process of elimination--to determine what the problem you are experiencing is. Check out the 700/900 FAQ for more information.

I highly suspect that one of those sensors is faulty, and as a result is causing poor running that is appearing to the computer, as another sensor fault (probably because the car is operating outside of the parameters of that sensor). This is just a guess, since it is hard to pinpoint anything from over data lines like this.

It could be an issue of the fuel pump getting weak, or dying altogether. If it was hard to start for a while, I greatly suspect a fuel pressure issue, followed perhaps by not enough fuel pressure to even start the car in the first place.

Establish whether the fuel pump runs for a second or two before you start the car, and you might find the problem. If the pump isn't acivating, it will cause exactly that problem. While the relays are a very good first step, the pumps on Regina(Bendix) injected systems are not known for their long term reliability... although that is not a guarantee that they will die early.
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a Brickboard.com Expat