I never noticed it before, but now my car is having some 3k hesitation, what is this caused by? It never used to do it before, but its doing it now. What should i check? I know theres like 1000s of threads on this and dont feel like reading them all...

 

i wouldn't waste my time reading them either -
you'll find the easiest way to solve the problem is to sell the car -

 

When my car was an automatic I never had the problem, after the 5 speed conversion it started but was pretty mild. Now that I have the Power FC the problem is gone again. That makes me think it was the ECU, but others have said they have had success getting rid of the 3K hesitation by cleaning, improving, and/or adding ground points/straps. Lots more info here - http://www.scuderiaciriani.com/rx7/3k_hesitation.html

 

I got rid of mine by Grounding my battery to my engine bay.

 

grounding did help me as well but adding my powerfc completely removed it. the hesitation your experiencing is caused by your ecu switching to your secondary injectors at around 2800rpm. the only real way to get rid of it is to upgrade you ecu with a standalone unit like the pfc, haltech, wolf3d, etc. the pettit and M2 ecus will not work.

 

mmmk.. well im gonna try regrounding since the problem started around the same time i changed the battery.

 

This has been debated to the end of the world and back.Ground straps help. I cleared mine up for a few months but it came back. It's rare and I really don't mind. My suggestion is get used to it. You can do a search here to find lots on this subject.

 

when i bought my fd last year it didn't have any hesitation at all, it was so smooth through the power curve. Then emissions time came around and i took off my dp, mp, and cb and put on all the stock stuff, then I also put on an air pump. Then the battery died over the winter and I had to get a new one. Then shortly after all that had been said and done I had the hesitation that I never had at 3000rpm , so when i switch everything back I don't think I'll have that problem. It has to be one of two things either the air pump(from it switching on and off around 3000rpm) or the battery needing more ground. I changed the plugs and wires too, but I don't think that had anything to do with it.