New guy here, I'm having this problem. My 6MT g35 Rpms when I accelerate will go up then go back down then go back up again or other times it stays at a certain rpm for a second or two. I have an exhaust, K&N drop in air filter, test pipes, and ztube. I have cleaned the throttle body and MAF and am going to install a new fuel pump, are there any other things I could check or do? Changed oil and spark plugs 2 days ago. I have no CEL, Could a dyno tune help?

 

Did this start happening before or after you cleaned the throttle body? These have electronic throttle bodies, if you move the butterfly plate while plugged in it can throw it out of calibration and possibly ruin the throttle body. Car will still run, but throttle activity and response will be off.

 

It was before I cleaned the throttle body, and I heard about the butterfly being super sensitive and was extra careful clean I cleaned it.

 

Auto or 6spd?

Does it do the same if you give it gas while in neutral and not moving?

 

It's a 6speed and no, it revs normal when in neutral. Just when I gun it it seems to lose power then picks up again. Usually does it 3-6th gear. 1-2 gear it's fine. A buddy of mine told me It could be that I was running lean. I have an obd2 and fuel trim for 1 and 2 were at 14-17%