Car starts, runs fine for a few seconds then starts to die, surging/pulsing Idle?

nissan
nx

#1

Hey everyone, having some problems with my 92 Nissan NX2000. i just finished changing the clutch on the car now its acting horrible.

When i start the car, it will run decent for like 2 or 3 seconds then the idle drops down till it almost dies, catches itself, idle goes up to about 500 were it will pulse around for a few seconds
until it dies. If i rev it it will stay running, kept it running for about 2 mins. but as soon as i let off it will pulse at 500 until it dies

After i changed the clutch it started up fine, it ran great for about 20 seconds before it just died. when i started it after is when the problem arose.

I took a video of the car running, which can be seen here. https://youtu.be/68h3mVZRLfU (It has never caught itself like that before and jumped up to 1000 rpms before. It normally will die at that point)

Sorry the video is really quiet, not sure what happened there. if need be i can get a video of the engine bay so its louder, was mainly focused on the RPMS

Here’s a few things i tried:
Checked fuses,
Changed spark plug wires, made sure they were all seated good,
MAF wires were rubbed a bit so i cut the MAF pigtail off one of my other sentras and soldered it on,
Changed to a good battery,
Changed fuel filter,
Added more gas (in cause gauge is broken),
Made sure all connectors are plugged in,
Checked around for vacuum leaks, found that one of the large hoses coming off the intake going to the engine had separated so i plugged them back in and nothing.

Any help would be greatly appreciated, I’m stuck on this and need a car running ASAP after my wife wrote the other one off a few weeks ago.


#2

Have you checked fuel pressure or volume


#3

Somehow I’d still suspect the MAF system. Try unplugging it entirely and see what happens when you start the engine. Try looking at this article, and it has links to others that might help.

http://easyautodiagnostics.com/nissan/2.4L/how-to-test-the-maf-sensor-1


#4

The problem might be that the Idle Air Control valve is hunting for the proper position.

https://www.rockauto.com/en/moreinfo.php?pk=817601&cc=1211713&jsn=346

This will cause the idle speed to fluctuate and the engine to die.

Tester


#5

@Tester

This is what im most leaning towards, browsing the fourm i mostly found that most people who are having similar issues (start car then it tries to die right after but if you hold your foot on the throttle it will stay alive) was solved by cleaning/replacing the IACV so this is where I’ll start when I get home this evening. I have a parts car which runs good so I’ll swap the IACV and see if it improves.