2000 astro need some help

I have read some of the other posts here and I seem to have the same problems that alot others have. I have a mis-fire in cylinder 6, ran a scan and showed trouble codes for a idle air control valve, then the maf sensor, then the tps, then the egr and then a mis-fire. I replaced all parts and had the injectors replaced by the dealer. complete tune-up and I am still experiencing the mis-fire. My tech guy at work suggested that it may be the ecm, and thats why its spittin out the different codes. Why does the ecm need to be reprogrammed by the dealer? please help! thanks.

Welcome to the forum!

It is EXTREMELY rare for a PCM to fail. Post the DTC's in the order they appear and we can help you diagnose the problem. The DTC's tell you what circuit needs to be checked. There are no DTC's that tell you to replace a part. Stop buying parts until we figure out what part you need, or if you even need one.

Thank you very much, I will get the DTC's and post them up. So far you have been very helpful.

here are the DTC that i scanned on my van, P0135,P0102,P0306

P0135 = O2 sensor heater circuit malfunction (bank 1 sensor 1).

This sensor is on the driver side, upstream of the converter. With the key in the OFF position, unplug the sensor and check the resistance of the ground circuit in the vehicle harness. It must be less than 5 ohms from the terminal to chassis ground. Turn the key to the RUN position, (do not start the engine) and check the heater circuit terminal for battery voltage. If both check OK, the most likely cause is a faulty sensor. This DTC must be repaired before troubleshooting any other DTC's. This DTC can and will cause many other DTC's to set. Post back your results.