240sx stall idle issue - stalls when i plug in maf

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240 T
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Car: 1993 Nissan 240SX Convertible

240sx stall idle issue - stalls when i plug in maf

Postby 240 T » Thu Oct 01, 2020 4:46 pm

So picked up a decently clean stock KA24DE 93 vert A/T and the guy that sold it to me because it had an idle issue - it basically shakes very hard until it stalls out.

I tried out what this guy did in this video - https://youtu.be/FNdY7Hqi0hk?t=265

and it turned to a different issue where it only stalls out when i plug the MAF or when i close the hood - https://youtu.be/1bf65zROXZs <--- thats my car and the problem

I have changed the MAF, i have cleaned the MAF , changed ECU's , changed TPS, cleaned the IACV, checked spark plugs, checked all the grounds i can find, I checked all the hoses around the engine. checked fuel lines.

There was a fuel leak near the tank , i replaced the fuel lines and that was that. The 240's EGR is deleted , the charcoal canister is also gone.

Oh i have also swapped wiring harnesses - So back to the og wiring from the previous owner - this wire is OEM with a lot of custom splices and cuts and a direct line for the knock sensor.

I have swapped wiring harnesses from another OEM A/T one off ebay - when i started the engine the car instantly stalls out . So i went back to the harness that came with a car and now i am basically all out of ideas & back to square one - my 240 stalls out when i plug in the MAF or when i close the hood.


I wanna blow up the stock KA & automatic trans before any swap considerations but any advice would be appreciated thanks NicoClub


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PapaSmurf2k3
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Re: 240sx stall idle issue - stalls when i plug in maf

Postby PapaSmurf2k3 » Tue Oct 06, 2020 9:38 pm

I can't tell in your video if the MAF is plugged in or not.

Couple suggestions - first, induce a vacuum leak or 2. Pull the fuel pressure regulator hose or something so the engine gets unmetered air. See if the problem gets better or worse.
2nd, the hose to your idle air control valve looks pretty kinked. Its prrrooobbbably ok, but you should double check it.
Third - if the MAF is plugged in, try shaking/moving the cable at the connection and also near the TPS junction area (where it comes out near the fuel rail) to see if it stumbles. Wiring around the MAF and other areas is notoriously bad on these cars.
If the MAF is plugged in and running until you close the hood, see if you can clock it or otherwise move the maf further away from the hood so nothing touches it.

Might also have to pin out the MAF and make sure its within spec. I'm not sure what it should read pin to pin, but its probably in the FSM.
https://www.nicoclub.com/nissan-service-manuals

240 T
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Joined: Thu Sep 24, 2020 12:21 pm
Car: 1993 Nissan 240SX Convertible

Re: 240sx stall idle issue - stalls when i plug in maf

Postby 240 T » Tue Oct 13, 2020 2:14 pm

Thank you for the reply man! i will try what you just suggested and let you know . the stock KA has some 215k miles on it so ill def try replacing the iacv hose.


it does not run with the MAF plugged in. and one of the TPS screws are stripped so i had to zip tie it in a position so it will idle just over 800 RPM. I will check out the pin out on the MAF one more time. might even try buying another one ? - the wiring on the MAF doesnt look modified compared to the other stock harness i got.

I was also thinking maybe it could be my air intake tube? i see some online that have 3 holes near the throttle body. mine has 2....

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Re: 240sx stall idle issue - stalls when i plug in maf

Postby PapaSmurf2k3 » Tue Oct 13, 2020 2:30 pm

You should really only need the intake tube to go to the throttle body, and the hose going to the idle air control valve. Everything else (like the hose going to the valve cover) is optional.

240 T
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Car: 1993 Nissan 240SX Convertible

Re: 240sx stall idle issue - stalls when i plug in maf

Postby 240 T » Thu Oct 15, 2020 9:18 am

So i just purchased an OEM 91-98 Nissan 240SX S13/14 KA24DE Air Reg AAC 22660 53F00 & Harness from ebay

i noticed some of the wiring for my AAC harness near the firewall looks spliced and electrical taped up.

it isnt the IACV.. i cleaned the one on mine... this is the AAC and harness for it.

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PapaSmurf2k3
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Re: 240sx stall idle issue - stalls when i plug in maf

Postby PapaSmurf2k3 » Thu Oct 15, 2020 2:42 pm

Is that the one near the exhaust? If so, just remove that thing completely. Its not even useful as a boat anchor.

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Car: 1993 Nissan 240SX Convertible

Re: 240sx stall idle issue - stalls when i plug in maf

Postby 240 T » Fri Oct 16, 2020 8:32 pm

Heres a video of the part im talking about. its weirdly wired and unplugged at the moment - https://youtu.be/1wgaA-Vo0XI



and as you can see i swapped out the iacv hose out front to an L shaped tube lol


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