I have two problems that may or may not be related.

The first is the lurching. My car lurches real bad sometimes when I use light throttle. I read around and some people say O2 sensor, but how do I test this?

The other problem which may or may not be related is my RPMs seem to be inconsistent at constant throttle.

For example, I will be in neutral, and I'll go to rev and shift and a lot of times my RPMs will drop even if my feet are in the same position. Like if I'm at a stop light and I start to engage the clutch and hold constant RPMs, my feet won't move but the RPMs will drop.

This can be very annoying when I'm trying to drive and all my shifts cause the car to jerk around like I'm still learning. I've been racing stick for years, so I highly doubt it's because I can't shift.

Any reasons the car would be dropping RPMs like that, and could it be related to my lurching problem?

 

Anyone? Generally the problem goes away after 10-15 minutes of driving, but for those first minutes it is awful and I really need to get this fixed...

For what it's worth...it's as if my pedal doesn't effect my engine when it happens. I press the pedal down and it seems to be stuck at -10 vacuum and then all of a sudden it recognizes the input and it launches forward and boost shoots up, and then it goes back down to around -10 and it starts lurching again. I think the lurching is actuallly caused by the engine repeatedly giving throttle and boost and then poorly idling when it doesnt recognize pedal input.

It also seems to rev fine when I'm in neutral...

 

Start with the basics:

* Check your throttle cable
* Test your TPS
* Verify your grounding points are clean

 

+1 ^^^^ make sure that the throttle cable is free and clear on it's track and not sticking.