Hello everyone and thanks in advance for any and all help


I have been rebuilding an '86 RX 7 (na) and ever since the very first fire up i have had a bucking/shuddering when under load (2,500 - 3,500 rpm). It will even occur under light load on a slow "granny" drive. I have searched all over these forums and elsewhere but can not figure out the problem. The closest i have come was reading a thread about a boost sensor and it fit all of my problems. I unplugged my boost sensor and my car ran nearly perfect (under 3,800 rpm)! I then plugged it back in and unplugged all the other sensors associated with the boost sensor but the bucking was still there. I thought maybe i had found the problem and ordered a new sensor. As soon as i got it i installed it but the problem was still there. I also began to notice a pattern in the severity of the bucking in correlation to the humidity. I thusly began testing wires and double checking all vacuum line i could see. As far as i can tell it all is as should be. I am currently running my car without the sensor plugged in so i can drive it as it is my daily but i want to fix it asap as i have heard it is very bad to run the car without it.


So please if anyone can help any and all info will be greatly appreciated. I dont know if the problem is a direct correlation to the boost/pressure sensor but it seems to "fix" the issue.

 

Have you checked your TPS?

Have you checked your grounds?
Proper RX-7 Grounding Procedures

 

How many threads need to be created for the same issue? Why am I having to ask this? You open up a new thread and your first response asks you to do what was precisely stated in the last post of your other thread.