todd5854

Sorry for general title, I want anyone searching for this to easily find it. I've been doing a lot of looking around before I removed my vacuum/emissions, and from what I've read, and how she's running after deleting those lines, I made the right choice!

1994 240sx s13 with stock KA24DE
NOT throwing codes, NO check engine light

Deleted and welded shut:
EGR valve and pump, both tubes welded shut
PCV valves on the bottom of the intake runners
EGR block-off plate was installed
Carbon canister removed

Idle is perfectly smooth. My car still has stock exhaust, when I'm sitting at a red light you can't hear or feel anything at all. Throttle response is amazing, and I feel like I gained some low-end power. Nothing super awesome, but definitely noticeable. Maybe I just had a vacuum leak, who knows.

Haha I can now change my knock sensor without removing the intake manifold!

IMPORTANT
Make sure you leave your gas tank vent line open (comes off the carbon canister) so the gas tank can vent. Without that you have a serious problem on your hands.

Diagnosing vacuum problems is now super-easy. The hard line from near the IACV (back of manifold near brake vacuum) goes straight to fuel pressure regulator, I only have the large vacuum line on the intake pipe hooked up, because the IACV requires it. The small one next to it has been sealed shut. The only other vacuum I have left is for the throttle body.

PCV now vents to atmosphere, instead of recirculating through the intake.

I modified the KA24DE FSM vacuum diagram as per my setup, if anyone is interested in seeing that.

Fuel economy? Couldn't tell you, my head gasket blew the next day so she's sitting

I've always seen people ask questions about what it does, what happens when you remove it, etc..

upcomintuner

I'd like to see the modified FSM, I'm replacing my head gasket currently and I plan on removing all the same stuff you did with the exception of the PCV system.

todd5854

Delete your pcv!! Its so nice to change your knock sensor without removing the manifold!

Just put a breather on the actual pcv on the block. Weld shut the openings on the runners!

upcomintuner

Yea that might be a possibility lol but I'm not sure of which vacuum lines to plug and which I can just take off. And idk what to do about the junction and sensors on the back of the head that I had to remove.

todd5854

Mine are all gone I might just take pictures and put them up, those damn vacuum diagrams are fucking confusing anyway. lol

shift_down

You know the vac lines connected to the back of the head? The onse where those 2 electrical connectors connect to? Did you guys remove those also? and what did you do with the connectors? Did you just leave them hang? And did you get a cel?

I'm in the process of this now.

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Ka24 t3/t04b + Z32MAF + 550 subys + Walbro 255 + enthalpy Tune + 91 octane

ProjectSQ

I'm going through the typical "bought a 240 after head gasket fix" and need some guidance what I can remove and plug...while I'm at it. So how's about some pix?

Atill93

i only have a vacuum line hooked up to my fuel pressure regulator now. is that all i need?

Kingtal0n

1. never remove PCV from any engine, they desire it. Every engine should have some form of PCV.
2. you did a bunch of work to the engine, and the next day the head gasket blew?

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5.3/4l80e/turbo 240sx playthrough:
https://tinyurl.com/turbo240

S14DB

Yeah, would have been better to put a catch can on the line between the PCV and the T bar.
I like how people gloss over this gem. Sounds like the vac lines were not relocated properly for a nice lean condition.

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Comments should be taken as Opinions not as Statements of Fact

todd5854

Here's the document guys. Dug long and hard for it. Damn I miss my S13 convertible. If anyone's selling one cheap I would love one. 19320 zip. I don't care how old this thread gets, Im always looking. Feel free to message me with cars.

I hope this helps some S chassis drivers. Feel free to distribute this as you wish.


In other words, EVERYTHING was deleted except the fuel pressure regulator, and lines going to the IACV. PCV and gas vent. vented to atmosphere from their original lines. I recommend putting a breather on your PCV valve to keep it clean down there. I do not recommend deleting the vacuum going to the valve cover, some engines need it, some don't. I won't get into it but if you like your piston rings intact, keep it there.


Todd

001 by todd5854, on Flickr

Atill93

I would love to see some pictures of the setup on the car too. I'll be putting my motor back together and in my car eventually and I'm sure I'll need a little guidance