My 88 TII sometimes has a lot more power than others and it will go back and forth randomly as i drive. i have taken care of all other drivablilty problems except for a slight hesitaion at 3800 but only when it's low on power. I suspect that the secondary throttle plates are not working correctly but i just cant find exploded views, videos, before and after pictures, that are good enough to make me comfortable with ripping something out of the throttlebody that i dont have money to fix. any direction would be greatly appreciated.

 

Did you read this in the FAQ section?

https://www.rx7club.com/showthread.p...55#post5131155

I have this hesitation whenever I accelerate right around 3500-4000 RPM
The dreaded 3800 RPM hesitation is cause 90% of the time by poor ground connections between the engine, the battery, and the car. Clean or replace all the under hood ground connections. On 86 model year cars , replacing/regrounding the pressure sensor's ground wire has helped (do not re-ground a 87 or later model year). If there is still a problem after that, look at cleaning the fuel injectors and (on a N/A) that your 5th/6th ports are operating correctly.

Good starting point.

 

just like the doc said its a grounding issue.

as for the tb mod, its really really simple. go to rotary resurection and read the write up there. pretty straight forward. only issue i had was removing the seconday butterflies. ended up drilling them out. and if you mess up dont worry, you can get a new used one for cheap

 

actually the hesitation is more often caused by a bad ECU ground. it is located UNDER the intake manifold (stupid right?)
the main harness ground is easy to find and repair too it is on the driver's side shock tower.

 

What do you think I just said in my post?

 

you said "poor ground connections between the engine, the battery, and the car"
that is not in any way the same as what i said. the way you put it you might as well just add random grounds between **** like i've seen people do for some reason. you need to fix that one specific ground which is hidden under the intake manifold.

 

You know for certain that it is that "One" Ground Mr I've been a member for a few months? I've instructed the person where to start. It's up to them to look at the FSM and check all the grounds!

 

lol i didn't know knowledge was based solely on how long you've been a member of this forum....
i've known that was the most common problem ground since i got my car bud. your answer was vague as hell, i was just improving on it.

 

Lets just say this. We agree to disagree. I gave the OP the whole are to look at not just one specific thing there. That way they can look at the "Whole" picture!

 

i do have the FSM and a volt meter i know how to find voltage drops and i really do appreciate the direction. is there a link that you know of for the JDM fsm becaue my motor was swaped for a japanese.
also is there a way to rule out the double throttle for the power loss by disconnecting the vacume line or something

 

oh yay i remember when my 86 did that, get rid of the cat converter, get 2 bottles of sea foam fuel system cleaner pour both bottles in half tank of gas,run til 1/4 then put 89 or better in, do away with the air pump, make sure u got good bat terminals it fixed mine!!!!!

 

I dont have any cats, air pump, EGR, BAC, AIC, i have a 3" turbo back, FCD and OMP delete. I would never seafoam a rotary.

 

voltage drop tests show a max of 0.07 volts between ECU and body, engine, and batterey. i got .025 from the battery to the body and engine. i have always belived that 0.5 was a big enough voltage drop do cause a problem. so less than one tenth of a bolt should not caus a problem right?

 

throttle body mod how to:

http://fc3spro.com/TECH/HOWTO/TBM/tbm.html

 

and more info on it here

https://www.rx7club.com/showthread.p...d+airflow+data

 

ya i used FC3SPRO i did it today i also sanded and cleaned the connectors from the back of the motor to the firewall. im happy with it. i think it's time to start posting some pictures of my seven now.