Odd hesitation

[BrandonR.]

Ok. I have a '95 Q45 automatic w/193k miles. No major problems, but it has a really strange hesitation sometimes.
If I press the throttle down too far, from a stop or in low RPM's between 1000 and 2300 , it sound like it wants to go but nothing happens. Almost like the engines getting choked or something. The trans doesn't slip or buck, but sometimes I hear a "pop" like a small backfire somewhere before the Cat when this happens.
If I press lighter on the gas it seems to "open up" and accelerates better, like I have to slowly push harder or little to nothing happens. After 3000 RPM's it runs like a champ, or normally at least. I usually start in 2nd and use 3rd unless i'm on the highway. It seems to happen alot less after it's warmed up, but it still happens.

My trans fluid is good, my oil is good, no smoke or odd smells, the traction control works fine, no misfires and i've cleaned the MAF (with proper cleaner). It happens with or without the air filter too ( I know, I shouldn't run it with out one but I had to check).
Could this be my throttle position sensor? What is the sensor on the other side of that? It looks just like the other one but oriented the other way, on the air intake by the throttle cables. Is there any way to test these, I have a multi-meter and know how to use it.

I know this problem can be hard to diagnose without actually driving the car, but if this sounds like a common problem please let me know.
On another note, do you think removing my Catalytic converters and going with straight pipes, just where the cats were, would help or even give it more room to breathe? Just a thought.....

[goody90q45]

.....If I press the throttle down too far, from a stop or in low RPM's between 1000 and 2300 , it sound like it wants to go but nothing happens. Almost like the engines getting choked or something. The trans doesn't slip or buck, but sometimes I hear a "pop" like a small backfire somewhere before the Cat when this happens......

Sounds like a bad fuel pump or fuel pump controller (FPCU). Have you had to replace either? At 193k it's long overdue if you haven't. Do you hear a buzzing coming from the trunk? Tee into the fuel line past the filter and measure the pressure. It should be around 35-40 psi.

[BrandonR.]

When I turn the key to the "on" position I can hear the fuel pump turn on (I guess you could call it a buzzing noise) for about 5 seconds and stop, then I turn the key all the way to start the car.
As far as I know, the fuel pump nor the controller has ever been replaced. I suspected maybe something along that line but wasn't sure. I don't know if I have the means to measure the pressure either. I'm guessing the pump is in the tank too. Hmmm. How much do either of those parts go for? Used or new.

[BrandonR.]

Would something like this help, or is this cheap crap?

http://cgi.ebay.com/ebaymotors/FUEL-PUM ... 3f0396097b

[Q451990]

Basically you need something like this to test the pressure. You would tee in between the fuel line after the filter and the fuel rail.



http://www.harborfreight.com/fuel-injec ... 92699.html

You can buy the OEM pump from www.infinitipartsusa.com for about $260... skip used for the pump since it's a wear item. http://www.infinitipartsusa.com/partloc ... atalogid=0

The controllers are available used and usually go for about $50, but it might not be bad yet. They usually fail in a way that the car won't run at all.

Heath