Ka24e SCV and emissions questions.. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

johnlpaul · 11-05-2015, 01:25 PM

Hey all.
My name is JohnPaul, I recently picked up an 89 240sx that im the third owner of. It's bone stock. Only has wheels that I had lying around from my last car on it.

Anyways..

Yesterday I started replacing the vaccum hoses located on the rear of the head, I changed about 75% of them at my job(work was slow) and then I ran out of hose.
I got to turn it on and the idle is rough. Way worse then it was before. Which is weird in my head because the hoses were basically soft and deteriorating in my hands when I pulled them out. I drove about 10 miles like this with no problems besides a rough idle and it sounded like it was running rich from what I could tell.

Today I started changing the remaining hoses after buying some more and then when I went to pull off the hose from the pressure regulator control solenoid valve(that's the name I got from another thread on here, the solenoid next to the SCV) and the tip broke.

I have been looking up diagrams and information for about 4 hours straight trying to figure out if I should remove it, or what I should do. I can't find the part online anywhere. I have no idea how to get it and I don't mind removing it all if it will fix this problem I just want to be sure that I'm doing it right. I continued to replace the rest of the hoses I could see and the idle is better. But still not back to how it was before I started.. To fix (hah..) this car.

I read about removing them but they were old threads with pictures missing and I'm still not positive about doing it all, I just want some re assurance in how to do it. I feel as though keeping those two on my car would be easier but I can't find a replcement anywhere.

Basically my question is, does anyone have the part number for that part?
Would one of the ends being broken off like that cause the rough running of the motor? I just need some insight and any help would be greatly appreciated. Thank you.

Gingersmurf · 11-05-2015, 02:10 PM

If the hoses were damaged from before, someone may have adjusted the idle RPM to compensate. You may also be also to adjust it for the new hoses?

Here is where the screw is on a ka24de. It's in about the same area on the single cam. i had to adjust mine after I boosted my car

johnlpaul · 11-05-2015, 02:18 PM

Thanks for the response, mine is a is 24E not DE but I think I might have explained wrong. The engine runs as if it's going to turn off. Kind of putting and the motor is visibly rocking back and forth a bit.

Gingersmurf · 11-05-2015, 02:27 PM

Quote:

Originally Posted by johnlpaul

Thanks for the response, mine is a is 24E not DE but I think I might have explained wrong. The engine runs as if it's going to turn off. Kind of putting and the motor is visibly rocking back and forth a bit.

I know you have a single cam. That was just the easiest picture i found, and it was already labeled. The idle adjustment screw is in the same area though, on both motors. If you have the car running above idle is it nice and smooth? if yes, then id try adjusting the RPM of the idle (using the screw) to about 750-800 RPM. I believe the factory service manual says 750 RPM, but it seemed low when i was adjusting mine. Just be gentle with it, don't twist it back and forth like a crazy person, the motor doesn't like that. i think maybe a 1/4 turn would be a good place to start?

johnlpaul · 11-05-2015, 02:42 PM

Weirdly enough it is at 750rpm at idle. It just sounds like a go kart now. If that makes sense. It sounds completely different than before and it lacks power in general. It still runs and turns on every time.

Gingersmurf · 11-05-2015, 02:49 PM

You plugged all the hoses into the right spots right?

johnlpaul · 11-05-2015, 03:21 PM

Spent the last hour checking that and yeah. They're all in the right spots. I want to just remove it all to see if it helps but I'm not sure if that's as easy as saying it.

johnlpaul · 11-06-2015, 09:57 AM

Quick update, I had to go work and had no other means to get there so I drove with it running how it was. After about a mile or two it completely cleared up and started running very close if not better than before. It hasn't gone back to idling or accelerating horribly since. Anyone know if it's safe to keep that pressure regulator control solenoid valve open like that?

Gingersmurf · 11-06-2015, 10:16 AM

Maybe just had some residue build up or something and it blew it out, or possibly a piece of that old cracking hose fell into a tube. If it is running better, then i say leave it?

johnlpaul · 11-06-2015, 03:32 PM

Right? Haha. It is running better. I still want to know about replacing that part though..

LuxExperience · 11-06-2015, 03:54 PM

I was having the same problem earlier this week. Take a look at the 3 (or 4) hoses right under the throttle body. Small vaccum hoses. The two on the right have vaccum and if the hoses are plugged, the car will start to shake and idle rough. The one on the right goes to the carbon canister and can be plugged if you're removing it. See if any of the hoses you replaced have crossed over or are pinched.

11-05-2015, 01:25 PM	#1
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Ka24e SCV and emissions questions.. Hey all. My name is JohnPaul, I recently picked up an 89 240sx that im the third owner of. It's bone stock. Only has wheels that I had lying around from my last car on it. Anyways.. Yesterday I started replacing the vaccum hoses located on the rear of the head, I changed about 75% of them at my job(work was slow) and then I ran out of hose. I got to turn it on and the idle is rough. Way worse then it was before. Which is weird in my head because the hoses were basically soft and deteriorating in my hands when I pulled them out. I drove about 10 miles like this with no problems besides a rough idle and it sounded like it was running rich from what I could tell. Today I started changing the remaining hoses after buying some more and then when I went to pull off the hose from the pressure regulator control solenoid valve(that's the name I got from another thread on here, the solenoid next to the SCV) and the tip broke. I have been looking up diagrams and information for about 4 hours straight trying to figure out if I should remove it, or what I should do. I can't find the part online anywhere. I have no idea how to get it and I don't mind removing it all if it will fix this problem I just want to be sure that I'm doing it right. I continued to replace the rest of the hoses I could see and the idle is better. But still not back to how it was before I started.. To fix (hah..) this car. I read about removing them but they were old threads with pictures missing and I'm still not positive about doing it all, I just want some re assurance in how to do it. I feel as though keeping those two on my car would be easier but I can't find a replcement anywhere. Basically my question is, does anyone have the part number for that part? Would one of the ends being broken off like that cause the rough running of the motor? I just need some insight and any help would be greatly appreciated. Thank you.

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11-05-2015, 02:18 PM	#3
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Thanks for the response, mine is a is 24E not DE but I think I might have explained wrong. The engine runs as if it's going to turn off. Kind of putting and the motor is visibly rocking back and forth a bit.

11-05-2015, 02:42 PM	#5
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Weirdly enough it is at 750rpm at idle. It just sounds like a go kart now. If that makes sense. It sounds completely different than before and it lacks power in general. It still runs and turns on every time.

11-05-2015, 03:21 PM	#7
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Spent the last hour checking that and yeah. They're all in the right spots. I want to just remove it all to see if it helps but I'm not sure if that's as easy as saying it.

11-06-2015, 09:57 AM	#8
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Quick update, I had to go work and had no other means to get there so I drove with it running how it was. After about a mile or two it completely cleared up and started running very close if not better than before. It hasn't gone back to idling or accelerating horribly since. Anyone know if it's safe to keep that pressure regulator control solenoid valve open like that?

11-06-2015, 03:32 PM	#10
johnlpaul Join Date: Nov 2015 Location: lancaster Posts: 7 Trader Rating: (0) Feedback Score: 0 reviews	Right? Haha. It is running better. I still want to know about replacing that part though..

11-06-2015, 03:54 PM	#11
LuxExperience Zilvia Member Join Date: May 2013 Location: Toronto, Ontario Posts: 225 Trader Rating: (6) Feedback Score: 6 reviews	I was having the same problem earlier this week. Take a look at the 3 (or 4) hoses right under the throttle body. Small vaccum hoses. The two on the right have vaccum and if the hoses are plugged, the car will start to shake and idle rough. The one on the right goes to the carbon canister and can be plugged if you're removing it. See if any of the hoses you replaced have crossed over or are pinched.