I have had concerns about my engine running lean. All four plugs are a bit more white in color than gray/white. I just put a new main pump and filter in. This has the plugs looking a bit better. While accelerating, I get a good role, but at ¾ throttle opening the car dogs just a little. If I let of the gas a touch it seems to build power back up. This may be better described as hesitation. The fuel pressure regulator and air filter are new and clean.

As far as I know the oxygen sensor is original or at least 100k old (how long I have had the car). My understanding is the car will run richer when oxygen sensor is toasted. Passed emissions with flying colors even at 196,000. Last gas mileage record was 22mpg but 80% is highway…not very good??? Plugs and cap are in good condition and plug wires less than 4k. FYI the gas mileage went down after new fuel pump from 25-22.

I feel that things are better, but I want to be sure in case I’m missing something.
It may be the turbo lags more than it has in the past.

Also, has anyone ever rigged up a test unit to measure fuel pressure actively while driving the car? The B230FT fuel lines and rail make it very difficult, as far as I can tell, to do this.