My 1999 volvo has a problem that I think the air intake might be the problem.
The engine starts and I let it warm up to operating temperature, but when I take it out, it boggs down on acceleration and slowly gets up to speed. Could it be in the Secondary air injection pump or the Throttle position sensor, or idle air control valve? Give me some hints. I have had this car for about eight years and I have had this problem before, but can't remember what fixed it.

It is not going to be the SAS pump. Check the air filter for rodent nest. Verify that the accordion hose is firmly attached to the throttle body, and it is not split or cracked. Look for loose vacuum lines around the air filter.

Is the throttle body clean? You should have a yellow labeled ETM which typically don't fail like the OE white label.
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Keeping it running is better than buying new

I checked the SAS pump and it is working. This is what I replaced when I first got the car. I will check for the labels and no rodent nest. I will continue to check other things.

Thanks again

Any chance of reading codes?? going at it without the code is going to be very time consuming. suck, squeze, bang, blow. one of those aint right. without codes. the variables are just too much.
try driving without the maf being connected.

and just because the mil is not illuminated does not mean there are no codes. pending codes can steer you in the right direction.

There are no codes. When I do check for codes, it tells me there is none.

Check your fuel presure!

If your engine is a turbo, check the intercooler connections. They must be tight or you will not build any boost pressure and flood the engine.

Check the 3 vacuum lines for the boost controller.
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Keeping it running is better than buying new

In diagnosing the problem, I notice when the engine is running and I pull the electrical connection on the air mass meter in the intake it does not stall. The same is for the idle air control valve. I will check to see if I am getting voltage reading at the electrical plug.

Never pull the MAF plug with the engine running, or plug it back in with the engine on. The car should idle nicely with the MAF unplugged, but driving is a different story.

Does your CEL light up? Is the bulb burned out? Have you checked for codes?
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Keeping it running is better than buying new

This is not a turbo.
I did check for vacuum leaks. I'm thinking something is wrong in the intake.
It just seems that it is not getting the proper air intake. I'll keep picking at it if you do not have any other suggestions.

Thanks