stutter/shaking under 2,500rpms

[Schneidy95]

Hi everyone. I read the Hesitation article and still cant pin point it. (1991 na)

I have a stutter/ bad acceleration/slight bogging, whatever you wanna call it under 2,500rpms. This happens all the time (warm or cold). Seems to do it in all gears also.
Lets say im parked in neutral, i rev the car slowly. the car/motor shakes and feels rough. Over 2,500rmps its smooth and feels great. This problem also happens while driving, although the shaking is not as bad.

I changed the plugs and gapped them, from what I see I should have put ngk pfr6b-11 but I didnt. Before I go spending $100 on ngk's I would like to see if anyone else has any recomendations.

I ordered the coil connectors(the ones that break) I sprayed vac lines with ether, and couldnt find a vac leak.
Help is appreciated! Thanks!

[ThisIsSparTTa]

1) You shouldn't be spending $100 on spark plugs.
2) If you have an NA, the correct plug is the PFR6G-11 http://z32.wikispaces.com/Spark+Plug
3) Have you checked for engine codes? http://z32.wikispaces.com/ECU+Diagnostics
4) Have you tested and set your TPS properly? http://z32.wikispaces.com/Throttle+Position+Sensor
5) Have you adjusted your idle properly? http://z32.wikispaces.com/Idle+Control
6) Have you tried disconnecting the MAF?

That's where I'd start.

[Schneidy95]

Thanks for the reply! The factory plugs that came in the car are ngk pfr6b-11 for the NA, and yes there $17 a piece. (work at caquest have a book) I dont have any codes thrown on the dash. It could still be storing it in the ecu?

[ThisIsSparTTa]

Check out Z1 or CZP for better prices on the
Plugs I mentioned. They are commonly used and accepted

[Schneidy95]

I will do that and check for codes! thanks

[Schneidy95]

Sooo I went and checked out the codes. I got 5 long 5 short.(55) so nothing stored. I checked the O2's. while in mode II (left O2) car running, the CEL came on and stayed on. Indicating rich? I then checked the right O2 and the CEL blinked constantly. Indicating Its good? So from what I saw I need to replace the left O2 sensor and it should be good? Thanks for helping out!

[ThisIsSparTTa]

I'd rather hook up a consult connector and look at all of your readings, but yea, starting at the O2 isn't a bad idea. You can get the Bosch one from Amazon, etc much cheaper than the "OEM" one which is the same model, just without Nissan's name on the package. http://smile.amazon.com/Bosch-13091-Oxy ... ords=13091