I have a 1986 Mazda Rx-7 and it runs fine at 1st, but after about an hour of driving it when i hit more than 3000 rpms it starts to like putter and sounds like the engine is flooding in a way, it jerks and stuff and i have no idea whats wrong with it, its annoying can anyone help and send me in the right direction?

 

Might wanna take a look at the tune. Just depends on what all mods have been done to it because pretty much anything you do to at power/change the air/fuel ratio is going to need a tune to make it run at its full potential. So I'd get it tuned first and go from there. Good luck man.

 

i did a basic tune up to it, and its all stock no mods have been done to it, so at this point im thinking it might be the fuel pump or injectors? but i need someone point me in the right direction if im wrong.

 

Is it a constant problem above 3k rpm or does it seem to 'stumble' and then run smoothly again?
Does it happen on light throttle only/ heavy throttle only/ both?
Does the engine continue to rev or does it get stuck at a certain rpm?
Does the engine tend do it more often when going around corners?
What did you replace during your tune up?
Answers to the above questions will help diagnose it.

Start with adjusting the throttle position sensor (TPS).
Fuel filter may be dirty and clogged.
Injectors won't usually get clogged unless they sit for a while so I wouldn't jump on those just yet.

 

No, once its starts its constant stumble but i tried turning off the car then on and it fixes it for a short period.
and it usually happens heavy throttle like 3.5k rpm to 4.0k rpm
The Engine rev's lower the more i try to push i over that.
The Engine also stumbles when i do the corners.
Gave it basic tune up, air, gas, oil filter and spark plugs.

 

The stumble during the corners is a common symptom of a dirty fuel sock. It's another fuel filter attached to the fuel pump. Pretty easy install, just make sure you relieve the fuel pressure before detaching the hoses on the tank cover. I'd try that and see if the problem persists.

 

Start by checking your grounds:
http://www.aaroncake.net/rx-7/grounding.htm

 

i just ended up adding an extra ground from the engine to body, couldn't reach the old one and didnt want to take everything apart to reach it, but so far its worked for my RPM hesitation, now all i need help with is for it to stop jerking at turns, and for my emergency lights to work, any suggestions?

 

got my lights to work, the wiring was bad, and no more hesitation since i added that extra ground and it turns smoothly! thanks for your guys input