Nissan Patrol 4x4 (Africa)

Lekke Spike keep us updated with your findings please

Had a re-think. Tomorrow I'm going to reconnect the actuator but disconnect the solenoid and run vacuum direct from the manifold. See what happens. Maybe, being direct "analogue" vacuum rather than ECM operated vacuum, it will work off throttle position rather than a lazy computer and I get best of both worlds

Hi Spike
Any update on your findings?

Interim update only. My plans changed and I haven't been able to drive that car as much as I intended.

Both mods work! I'd like to think that the Version B with just re-routing the vacuum pipes and leaving the butterfly functioning works best but it may be in my head due to not having driven enough distance and enough variety of conditions yet to determine if there is any negative side-effect that bothers me. Driven plenty with version A.

The biggest hassle with changing over from mod version A to version B was dropping the circlip while reconnecting the actuator rod on the butterfly. It's gone to the same place that all 10mm sockets go when they disappear. Mine is now currently working without a circlip It seems to stay on though so OK till I find another tiny circlip to match

I'll probably change back n forth between the two mod versions a few times till I make a final decision. Definitely not going back to standard though!

Summary of the mods:

Version A: (Bypass solenoid and lock the flap closed)
Unplug the solenoid
Disconnect the activator arm and cable-tie it fully turned clockwise

Version B: (Bypass the solenoid AND vacuum canister and run the actuator off engine vacuum)
1. Leave activator arm connected

2. There are two pipes at the bottom of the solenoid. The top one of the two is for the activator (the other comes from the vacuum canister on the drivers side of the motor, see step 3). Blank off the end going into the solenoid and connect a new long pipe to the steel pipe going to the activator

3. On the top of the engine, drivers side, there are three vacuum hoses connected. Two thick ones and one thin one. The thin one goes down to the dedicated vacuum canister. Disconnect this thin hose. Blank it off and tie it somewhere safe. Take the end of the new activator hose and plug it on the motor. You basically bypassed the solenoid AND the vacuum canister

I hope that attempt at describing the steps is not too complicated

For a first attempt I'd say go for Version B first. Changing the pipes is easier than messing around with the circlip on the actuator in Version A, and if you decide to try Version A later the changed pipes don't matter.

Edited to add photos.
Red shows the new pipe routing
The yellow in the one photo shows the old pipe tied up and the solenoid wires tied up

Ok so I've driven a fair bit and I'm sticking with the "B" mod, in other words bypassing the solenoid etc and connecting the actuator direct to engine vacuum.
Works great for me.

Hi Spike
I did your option B ,and love how the Patrol drives now in town ,open road revs are alot smoother,open road fuel economy is good/better,in town i dont drive too nicely so havent checked that out thanks for your post

I was just communicating with a Patroller about this mod and it occurred to me that I should put a clarification here for guys who may be apprehensive.

This so called "Option B Mod" that has been advocated here doesn't disable the system as such. The PVA system of lengthening and shortening the inlet length remains functional. The mod basically just entails bypassing the input of the ECU involvement in that decision, thus removing the erratic activation/deactivation of the system.