Replace the plugs with OEM NGK's and re test it. I would also check for other vacuum leaks. The dist. is more than likely not the culprit but I wouldn't rule it out completely.enigmaticsb said:1993 Nissan Sentra SE 1.6L Manual. When reaching 35-40 MPH range there is a light-moderate thud/jerking when the accelerator is tapped to increase speed. It will do it at other speeds but not as noticable. Idle RPM is 1500 when cold and eventually lowers down to 1000-750.
Also, I noticed a strange behavior when the car is in neutral, I lightly press down on the accelerator and hold it steady and the RPMs go up and down in a repeatable pattern until I release my foot from the accelerator.
This all started to happen after a leak was found in a vacuum line, before the leak was fixed the car had very poor acceleration and would often die at an intersection when in idle.
I took the car to a nissan dealer, they told me it was a bad distributor but I would like another opinion since I don't really trust them 100%. My regular mechanic wasn't really sure what it could be off hand. I told the nissan dealer I had replaced the rotor, cap, and plugs with bosch platinum plugs, the kind that you don't have to gap, I didn't replace the wires. I told the dealer that I had also adjusted the rotor by hand and they then told me that in my car I should have never turned the rotor and that could have caused the distributor to go bad.
I have been reading alot about the NGK plugs and plan to get those soon. However in the mean time I would like to know if the distributor could be the culprit. Any ideas on what to check and or replace would be helpful. Could it possibly be cause of the aftermarket rotor or cap, or the type of plugs I am using?