I have 97 tacoma 2wd with a 2.4L 4 cylinder.

When I bought the truck (111K miles), I checked the throttle body to see if it needed to be cleaned. I have never seen a throttle body so dirty. I had to scrape out the gunk with a razor blade. I could not get a gasket that weekend and cleaned it with it still on the truck.

It has been about 27K miles since then. I pulled off the throttle body last weekend to check it and clean it. Was not nearly as dirty, but there was a pretty good build up on the back side of the butterfly.

The truck does not make the power that I think it could, and the gas mileage is not great either. I average about 16-17 mpg.

When i pulled the TB noticed that the port leading to the egr valve is very dirty. Could not get it clean. There is still a lot of gunk. I have been thinking that the egr might be stuck open.

Just wondering if anyone has had this problem and knows what might be causing this. I live in Alabama and don't have emission testing. So disabling is a possibility.

Also wondering if I will likely get improvements in my engine performance if I replace my O2 sensors.

Thanks for reading.