Hello,
If you have already replaced the swirl control valve the first thing I would do is disconnect the vacuum line between the swirl control valve, and the swirl control valve solenoid, and connect a vacuum gauge (like a mighty-vac) to the solenoid.
This will tell you two things:
1. you will know if the solenoid is actuating the valve
2. you will know if there is a vacuum leak between the solenoid and valve.
Next, with the engine off. Disconnect the vacuum line from the solenoid end, and see if there is a leak in the line, and see if sucking the air from the SCV makes the rod for the intake runner flaps to move.
If you have a bore-scope, you can run through the throttle body, and see how the intake flaps are doing. They may be clogged up, broken, missing, or simply stuck open.
Lastly, with the engine running, connect your vacuum gauge to the solenoid, and see if you get changes in vacuum, as this is what should be actuating the SCV.
If you have any other questions, or need more information, let me know, or, if you prefer one of our certified shops diagnose the issue, see the link below: http://repairpal.com/nissan-within-10-miles-of-gordon-wisconsin-54838
I haven't replaced the scv. I replaced the scv solenoid. I don't have a vacuum guage or a scope.. I think the vacuum line is ok. And I did put my finger tips of one hand on the end of the scv and ran the throttle manually with my other hand. I could feel the actuator and valve open at higher RPMs. Now if I reach back and oper the scv with my finger while it's idling it does seem to Change the way it runs. Seems to smooth out. I have also checked the TPS and tested it with a multi meter.. the thing is there I do not get any voltage fluctuations on signal wire when I manually move the throttle. The voltage stayed constant at like 2.4v and it should go up and down in relation to throttle movement..Will the scv problem affect the TPS performance? I don't have any code showing for TPS. I only have the p1130 code showing up.
OK, if you do not get signal voltage fluctuation when the TPS is rotated, and the voltage to the TPS is higher than the output/signal voltage, it is bad. When the TPS goes bad in this manner, there will be no check engine light, however, the SCV position is relative to the TPS position, since it opens under high vacuum, and closes under low vacuum, so the computer may think the TPS is good, and the SCV is bad. Retest, make sure you get the same result/that testing was done accurately, and replace the TPS if needed. A little mighty-vac is probably under 20 dollars, and you really should have one, especially for a 96 D21. Try plugging the line from the SCV solenoid to the SCV. If the idle smooths out, you probably have a vacuum leak in the SCV. This would allow it to move slightly, but not hold pressure. Another way you can test this, speed the engine up by hand, and after the valve opens, clamp the vacuum line to trap vacuum in the canister of the SCV. If the flaps still return to the closed position, probably a vacuum leak.
Makes sense. My initial instinct was to the TPS after I had texted it with the multi meter but I was waiting to get my code reader so I could check what codes were showing and it came up scv code so I figured maybe the TPS wouldn't work correctly if scv solenoid was bad. I hope to be able to check this weekend.. thanks for your help
Oh no, you were right the first time, as long as it tests bad next time, and you can guarantee your accuracy (you can check the new part to determine if you were accurate. Here is the cool thing, using a multimeter, with the TPS removed from the vehicle, with no power source, you can still test it. It is a potentiometer, so instead of measuring the outgoing voltage, you can measure the resistance between input and output signals. No ground needed, either. Just swap the multi-meter to ohms of resistance, and turn the TPS by hand. I hope I'm not insulting your intelligence by describing all this, most people do not understand the TPS enough to test it. Great find!
Update.. problem solved.. slapped in new TPS and cleared code. Idles beautiful and no cutting out at 1700rpm and no more p1130 code.