Starts and almost stalls

[tahawus84]

When I start my 02 Trailblazer then engine starts fine but then the rpms go down to about 500 for about 2 seconds then come back to normal. What could be causing this? The car seams fine otherwise.

[Twin1]

Could be several things, When was the last time you changed your fuel filter? Throttle body plate could be dirty and sticking.

[BlulytesTB]

I have noticed the same at different times, sometimes then, also when just sitting at a light.

Dealer flashed computer or updated software... fixed!