I got a 86 RX7 and has hesitation at about 4 rpm. I switched the maf and still hesitated. Then i swaped the injectors and now it sounds like a bolcking sound goin past 4rpm? Need help if you know anything plz let me know.

 

Is it just a hesitation? Or will it not go past 4k at all? If the first, try adding an extra ground between the pressure sensor and the chassis. This fix was in a mazda service bulletin for '86 models.

 

The blocking slowes it down so it really wont let it go past it but if i slowly step on it, it will pass but with hesitation.

 

Sounds like the secondary injectors may not be firing at all. At 3800 rpm, primary injector duty is cut in half & the secondaries are supposed to match them. If they do not come on, you will effectively get a fuel cut at 3800.

The quick and dirty check is to unplug both of the secondary injector clips and take it for a drive. If the behavior doesn't change, it's safe to assume the secondaries aren't doing anything at all.

 

this problem is the most common with FC's.

a stand alone engine management system is by far the best way to go to deal with this. however, if it is "overkill" for one to purchase that, start re-doing all your grounds.... yes... ALL OF THEM