Lost my turbo boost on Saturday. Really down on power, will not wind out up at 3000 RPM.

So, i had the parts and thought I'd eliminate the turbo wastegate issue and swap over to the gsxr pressure mod. Did the pressure waste gate swap. Did it correct, (EGR and flapper still in place, just not vac on them now) had good boost for a trip around the country block on Sunday morning. Drove to work today (30 miles). had good boost and felt strong, but just as I got to work it seemed a little weak again. Got in to drive home, again the car was a dog. I had a max out of 11-12 psi boost, car had no get up and go. A dog again. It just seems to not want to wind out, especially under load (up incline etc). I really think I have plenty of turbo, but maybe light on the fuel side??

I think maybe my turbo woes were not the vac system but a lack of umph on the fuel side and the OEM system was just holding back. Now I have a boost on system default and have some boost but again the motor just can't seem to wind out or make power.

Just my thoughts, would like advice on what to check next. ALDA? (How to check), something else? Please help me rescue my old 300D!

When was the last time the fuel filters were changed?

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Jim

Yeah, good points. I hadn't got to them yet. The primary is probably <6 months and 6-8K (doesn't look bad, a little discoloration and can see through just fine). The 2ndary is probably 18 months, maybe 20K can't tell further of course. I'll replace both as a first step along with the air filter I guess.

This was an all of a sudden situation, then fixed temporarily then back. Sure seems like some crap in something somewhere. Idle seems normal. I also noticed, it doesn't give me the black puff when I stand on it like it historically does. I guess that would be consistent with lack of fuel?

I changed my primary and 2ndary filters and still the car seems to be very doggy. I get 11-12 psi of boost and it winds to around 3K on the tach but my 0-60 speeds seem quite slow (maybe 18-20 seconds). The car doesn't have alot of power it seems down at the 30-50 mph range. Any thoughts on where to go next to look for problems?