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

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240 T
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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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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.

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

Postby 240 T » Mon Oct 26, 2020 8:45 pm

i need some clarification on for me what kind of IACV should my 1993 A/T S13vert have ?

is it https://imgur.com/4SR6ZHf

or is it https://imgur.com/oi4PNTi

because i think i found where the problem lies lol... the wiring that i bought recently that goes to IACV and AAC has 3 connectors - https://imgur.com/xmJpvCR

and the wire that came with the car looked like https://imgur.com/gIjIc2q -

that 3rd wire was never plugged in and wiring was cut... but the New wiring that i bought does Not fit in the gray input for the IACV that is currently in my car - https://imgur.com/QBqCmtV

the gray input on the IACV car is similar to to the AAC input that i purchased with the IACV wire - https://imgur.com/UFEferB


im wondering if i have the wrong IACV on my car.? Should i buy a IACV that can plug into the purple plug? or if i could just do the wiring myself to fit on the current gray input ? https://imgur.com/oi4PNTi



any advice is greatly appreciated thanks
Last edited by 240 T on Mon Oct 26, 2020 9:02 pm, edited 1 time in total.

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

Postby PapaSmurf2k3 » Mon Oct 26, 2020 9:00 pm

I went into your post and fixed your image tags, so the pics show up now.

Looks like someone cut one of the wires there. Your wiring in general from that video looks pretty knackered and unfortunately that's something that is super difficult to troubleshoot from the computer.

I've always seen/used the IACV in the top picture personally. You might have one from a SOHC car (89-90) or a truck or something.
Realistically though, you SHOULD be able to run if you just manually adjust the idle air control screw all the way open on the back side, and maybe induce a vacuum leak like I was saying before (pull the fuel pressure regulator hose or something).

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

Postby 240 T » Mon Oct 26, 2020 9:08 pm

@PapaSmurf2k3 I greatly appreciate all the advice youve given me fam. I really do - Thank you


Which screw do you mean for the idle air control?

- at this point im ready to pull the entire engine and transmission out and just take my time and rebuild it all!!!

I will check for other vacuum leaks. but the issue still occurs - when i plug in the MAF my entire engine stalls out... i think it has to do with this IACV for SOHC

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

Postby PapaSmurf2k3 » Mon Oct 26, 2020 9:10 pm

Image there's how you can try and adjust the valve open.
And here's a good article about what you need and don't need on your manifold, and some good pictures around the area.
https://www.nicoclub.com/archives/intak ... embly.html

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

Postby PapaSmurf2k3 » Mon Oct 26, 2020 9:14 pm

You can always just pull the intake manifold by itself... no need to take the engine and trans with it haha.

So if you pull the vacuum line at the fuel pressure regulator and everything gets worse, then yeah, you probably have other vacuum leaks somewhere and are struggling to get enough fuel to the engine. At that point you can spray some starting fluid (or similar combustible) around the area (not near the exhaust) and see if it idles up at all. That should help you locate the vacuum leak.
The other thing you can do is pour some fuel down that vacuum line that you pulled and crank it up and see if it runs well for a second or 2. That also tells you you're not getting enough fuel. Try it both with and without the MAF plugged in.
If you pull the vacuum line and everything gets better, then yeah, you've got some kind of idle air control valve issues. Try opening the screw as much as you can (counter-clockwise) to see if it gets you to where you need to be, otherwise you'll need to start replacing stuff.

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

Postby 240 T » Mon Oct 26, 2020 9:17 pm

:squint: wow! great advice once again dude! I will DEF try all of this tomorrow and report back!!! :bigthumb:

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

Postby PapaSmurf2k3 » Mon Oct 26, 2020 9:19 pm

Good luck! We're here for you! Deep breaths :rotfl :rotfl

Idle issues can be super annoying.
I meant to ask - does the car run if you start it up (with the MAF plugged in) and give it throttle?

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

Postby 240 T » Mon Oct 26, 2020 9:26 pm

yes it does start up with the MAF plugged in on cold start. but as soon as the engine gets warm it stalls out.

i can give it throttle to keep it alive but as soon as i let go, the engine just dies - not to mention the temperature gauge on my speedometer just died on me as well :rolleyes: - stay tuned for that thread lmao

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

Postby PapaSmurf2k3 » Mon Oct 26, 2020 10:01 pm

Ok, that's good info to have.

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

Postby 240 T » Wed Oct 28, 2020 12:54 pm

im thinking about buying this IACV from a s14- with the compatible input...

https://www.ebay.com/itm/392954435925?c ... jXEALw_wcB

is it worth buying? or could i just replace the input on my IACV with one like the purple part/ replace the wire harness plug?

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

Postby PapaSmurf2k3 » Wed Oct 28, 2020 1:17 pm

I never advocate hacking in to the factory wiring. If at all possible, adapt the part to the harness.

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

Postby 240 T » Mon Nov 09, 2020 9:18 am

So after basically trying everything else - inducing a vacuum leak and soldering up wires to go into IACV .. still no luck :facepalm: - when i plug the maf in the car stalls out. but runs fine with it off and i tried revving it past 2500 with maf on and i get nothing but white smoke so my headgasket is probably cooked too.

I will be pulling the whole damn motor and trans out today. I couldnt find any decent videos about pulling out a ka24de with A/T so im going to attempt and make one as i go with my go pro.

Im going to try and rebuild the engine myself... i wanted this car to have manual transmission anyway so i might as well just get it over with.

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

Postby PapaSmurf2k3 » Mon Nov 09, 2020 10:10 am

Did it get any better or worse with the vacuum leak?
Also, if you're pulling the motor, I STRONGLY recommend putting a new wiring harness in there from wiringspecialties.com

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

Postby 240 T » Tue Nov 10, 2020 8:05 am

it made the vacuum leak worse when i tried to test out leaks. sometimes the car would start and stall out immediately lmao.

So today will make it day 2 of pulling the motor and A/T trans out. and when i was draining out the oil from the oil pan i saw grayish.. milky/cloudy oil poured out... so i guess ill need a new head gasket sigh. i hope its nothing too bad .

i may just buy a rebuild kit with head gasket included, after i dismantle the KA24DE


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