CA18DET Secondary Butterflies Control System

Discuss topics related to the CA18DE and CA18DET series engines.
User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Awesome!


User avatar
biosehnsucht
Posts: 1839
Joined: Thu Feb 26, 2004 10:20 pm
Contact:

Post

I don't know what's wrong with the OP in this thread but the image tags are gone somehow (the images still exist in the same place on my server, the actual tags are missing in the post... ) and I can't seem to edit it.

Here are the images that should be in the OP:

Vacuum Diagram from FAST
Image
http://media.impactblue.org/imagepost/C ... iagram.gif

Airflow when solenoid is off
Image
http://media.impactblue.org/imagepost/C ... id_off.gif

Airflow when solenoid is on
Image
http://media.impactblue.org/imagepost/C ... oid_on.gif

Volvo Vacuum Pump I refer to
Image
http://media.impactblue.org/imagepost/C ... m_pump.jpg

Wiring up the Volvo Vacuum pump (it might be wired differently depending on the model you get, as someone reported I think in this thread)
Image
http://media.impactblue.org/imagepost/C ... wiring.gif

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

I think I edited it a while back. The links were broken (they had been truncated to "www.blablabla...." so I didn't have the complete link to correct it). I'll see if I can get these images back into that first post again so it easy to find all the info.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

OK, fixed!

CCB
Posts: 15
Joined: Tue Apr 16, 2013 5:20 pm
Car: s13

Post

biosehnsucht wrote: Vacuum Diagram from FAST
Image
http://media.impactblue.org/imagepost/C ... iagram.gif
Can anyone advise whether leaving that yellow line open to atmosphere is OK? I have it setup this way on my car, engine seems to run fine. I've had a look at the scenarios where the solenoid valve operates and there does not seem to be one where an air leak might be introduced into the system via the unconnected yellow hose, but just seeking some opinions as I might have missed something. I've already plugged up the nipple take-off on the MAF-to-Turbo intake hose.

Thank you

User avatar
biosehnsucht
Posts: 1839
Joined: Thu Feb 26, 2004 10:20 pm
Contact:

Post

Technically you're experiencing a small indirect leak but realistically since it'll be buffered through the butterfly control system and never directly 'open', it won't matter other than a small chance of whatever unfiltered air might do (which is probably not much, unless you're in a desert) to the butterfly control system.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Yea, that is a REALLY small amount of air that's being leaked, so it shouldn't matter.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Just in case anyone is wondering, part number 14956-35F10 for the solenoid is actually used on the 1989 - 1991 240sx, according to www.Nissanpartszone.com atleast.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Buddyworm,

if you ever jump back on and see this, could you PM me? I have some questions about the NIStune table to adjust the butterfly valve solenoid.

Red_CA_Silvia
Posts: 35
Joined: Sun Jul 24, 2011 1:16 am
Car: CA18DE(T) S13 Coupe

Post

Gonna apologize first, might be a bit of a dead thread, but...

In looking through notes I'd made about the updated "Volvo" method and getting all my ducks in a row on the upcoming complete engine overhaul I'm gonna do.. I found out that my FPR is plumbed straight into the intake, with no solenoid controlling it. Was wondering how necessary that solenoid would be and if it is.. Could I double up on the "Volvo" method and have another electric vacuum pump run my FPR?

I do have the NISMO FPR upgrade.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Your FPR should be connected to your intake. The solenoid should only control the butterfly actuator.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

No need to have the solenoid for the FPR. We always recommend sourcing the vac straight from the intake plenum. The idea behind the solenoid is that the ECU references the FPR to atmosphere during cranking to increase fuel enrichment and to flush any vaporized fuel out of the rail. In practice the effect of NOT having this system operating is negligible. The engine might have to crank over once more than it would have otherwise. NOT worth the effort of hooking it back up.

Red_CA_Silvia
Posts: 35
Joined: Sun Jul 24, 2011 1:16 am
Car: CA18DE(T) S13 Coupe

Post

Awesome, thanks!

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

""Now, the CORRECT method can be even simpler than the above:

Switched 12-volt power is still connected to Pin 1 on the pump.
Constant ground is connected to Pin 2 on the pump.
The ECU butterfly control wire (Grey wire from the OEM butterfly solenoid plug) is connected to Pin 3 on the pump.

So, when you start the car your switched 12-volt power kicks the pump on. When wired this way, as long as the key is in Run position, the pump motor will function.

Now for the fun part: Your ECU controls the amount of vacuum "seen" by the butterfly actuator by changing the solenoid's duty cycle. It does this by rapidly closing and opening it's ground circuit (grey wire) to achieve a specified pressure at the butterfly actuator by opening and closing the trap door inside the vacuum pump, much like an electronic boost controller controls how much pressure your wastegate sees. Essentially, they "vent" pressure in short bursts to control the actuator diaphragms.""


So this is the way I should wire up the Volvo pump correct? No relay or anything is needed like it shows in the main post of this topic right?

User avatar
louiswun
Posts: 119
Joined: Sun Jan 27, 2008 5:33 am

Post

Refere to Nistune ECU director Matt, ECU is switch on/off for the solenoid refere to engine load vs rpm, it is not controlling the duty cycle, only in different rpm, switch on or off accroding to the air flow quantity.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Im mostly just curious about wiring.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Without having the pump in front of me to test I'm not sure. I think the reason for the relay is so that the pump is turned off when the release solenoid is turned on. Without wiring that way, the pump runs constantly and when the release solenoid is activated, the running pump MAY still provide too much vacuum to allow the valves to open. That's just speculation though. It could also be that the release solenoid closes the vac pump off completely. If that's the case then the relay isn't needed. With out bench testing it, there's no way to tell for sure.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Oh okay I see. Basically just hook up a vacuum gauge on the nipple that would be connected to the butterfly valves and wire the pump with a power and ground to turn it on. it should pull vacuum at this point, and then once I ground the solenoid wire, the vacuum should dissipate.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Exactly

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Well i received the cruise pump today. I did some bench testing and found that when the solenoid is grounded, it will register a vacuum and when the solenoid is open, I see almost ambient pressure. So I'm guessing that when connected to the ECU, the ECU will ground the solenoid until "X" amount of RPM and then open the circuit to allow the butterflies to open. Is this correct?

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Yes, that's how it should work

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

Sweet. Now im pretty excited lol

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Yea, it's going to be really simple to wire up actually. I can't see any need for the relay now.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

I just wasn't sure how the ECU controls the solenoid in the stock setup, that is where my main concern lies. But either way, it is going to be grounding it so it should be fine.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

My last concern with this is where do you get the terminals to add the wire in for the butterfly valve to the harness. I'm using a wiring specialties harness so there is no plug or connector for the butterfly valve actuator.

Red_CA_Silvia
Posts: 35
Joined: Sun Jul 24, 2011 1:16 am
Car: CA18DE(T) S13 Coupe

Post

@sjbsuperman1425 - I've got the same harness, and I noticed a lack of butterfly solenoid connector, also. Looking back through the thread I found that it is a grey wire from the ECU on pin #8. I'm going to rob my old harness of a wire and pin, and add it into the new ECU connector. I should (barring thunderstorms in my area) have my engine installed by Friday, and I'll let you know how it worked out for me.

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

Yea, I didn't know the wiring specalists harness lacked the butterfly control solenoid. You'll have to add that wire back in there. My info also says pin 8, Gray wire.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

I know I'll have to add it, but where can i get the physical pin terminal to go into the ECU connector to wire it in? Does that make sense?

User avatar
float_6969
Moderator
Posts: 19853
Joined: Mon Aug 26, 2002 1:55 pm
Car: CA18DET swapped 1995 Nissan 240sx (too many mods to list)
2015 SV Leaf w/QC & Bose (daily)
Location: Topeka, Kansas
Contact:

Post

You'd have to rob it off of another loom, or maybe if you contact wiring specialties and tell them the situation, they can get you a pin and some wiring. Really, they probably need to know that they're not putting a wire in there that they should be so they can correct it. For them, to add one more pin to the plug and a short length of wire wouldn't cause them any big issues.

User avatar
sjbsuperman1425
Posts: 2889
Joined: Tue Nov 06, 2007 2:24 pm
Car: 1989 Nissan 240sx
CA18DET
Location: Bay City, MI
Contact:

Post

I'll update my experience with the Volvo cruise control pump.

The three wires are easy to wire up to make the pump function. When turned on the pump will pull around 15 vacuum. The only complaint I have is that it is a little loud. Now bear in mind it is in the garage, with the hood off, but it still makes quite the noise.


Return to “CA18DE / CA18DET Forum”