If its a K&N oiled filter throw it the F out. The oil screws with the MAF. Put in stock and clean the MAF. That's kind of what I meant by "special". K&N's are specially made to screw up MAF sensors. Bet you will be fine after.

 

No, it's stock. Not an oiled filter

But I do regret to inform the masses, i drove around just now after having the car sit for a few hrs (MAF still UNplugged) and the symptom came right back.

I'll still check the sensor with a DMM, but back to the drawing board nonetheless.

 

Get yourself a scanner and quit the guessing game. If you have a smartphone or tablet you can use a program called Torque along with a cheap Chinese scanner off of DX.com or Amazon.

 

have we ruled out clogged cat?

 

Yes. I installed new muffler/ direct fit cat/ 3 Oxygen sensors (ACDelco) just a few days ago.

And I just ordered an OBD2 dongle as "burned" had recently suggested.

Im researching Fuel Pressure Regulator and the Fuel injectors right now. I have a feeling it may be the faulty spider assembly.
(I hit 160,000 miles today)

 

fuel regulator is all about leakdown, your test results earlier dont show me any signs of immediate problems. Its clearly not 100% but driveability shouldn't suffer. But if a poppet is sticking it "could" cause a problem but you would surely get a misfire code with that. I would get a scan tool with data readouts form the sensor and monitor it when it's messing up to see what is out of whack

 

Yeah, I did just order a wireless OBD2 dongle last night and should be able to mess with it when it get here in a week or so. I also have a can of seafoam im gonna use and see how it runs.

 

I unplugged my MAF and it runs way better. But my check engine light came on. I plugged it back in and it's still on. Would the MAF have caused this? Or is it something else?

 

I think the check engine light 'is still on' because it was set and needs to be 'erased' from the PCM memory. Some are automatically erased after so many restarts without the DTC showing up.

 

my 95 blazer was doing the exact same things...sluggish/no power after warmed up loud fan noise. i replaced fuel filter sensor after sensor still wasnt fixed i got frustrated and sent it to a mechanic friend of mine to look at he adjusted the timing after that the truck runs great no issues no loud fan noise has great power and much better gas mileage im not much of a mechanic but whatever he did to the timing sure fixed my issues that are the same your having hope this helps