Range Rover P38 # 073 - Plenum Air Filter and Engine Tuning

Winter is coming, and it's time to have a working plenum air filter to avoid snow and other debris to enter the cabin air intake system. The windscreen side trims, lower weather strip trim and wiper arms needs to be removed so that the plastic covers can come off to access the plenum air intake filter. Just take care now to break the weather strip on the side trims and save the clips where you can.
I'll also install a Ronbox Synergy 4 VP chip tuning device into the green P38. I have one in my black P38 already and there's quite a huge difference in response between the vehicles. The installation is quite straight forward. The only "hard part" is tapping into the fuel pump wires (2 of them). I prefer to do it at the engine ECM connector instead of the pump. The other connector is just a plug-and-play Y-connection at the MAP sensor which is at the fuel filter on the left side of the engine.
The Ronbox Synergy 4 can be found here:
www.tuning-die...
I'm not affiliated or receiving any sponsorship from Ronbox.
Other parts you might need are:
DA610065L Plenum cover screw (14 pcs)
AWR1675 Plastic nut for above screw (on chassis 14 pcs)
BTR9548 Plenum air intake foam piece
BTR9549 Plenum air intake foam clips (9 pcs)
BTR4428 Windscreen lower trim clips (11 pcs before 1999, and 14 pcs from 1999 and later)
AMR3915 Wiper arm plastic cap (2 pcs)
NH108041L Wiper arm 13mm nut (2 pcs)
Here's a drawing and Google Sketchup of the plenum air filter in case you want to make your own:
drive.google.c...
drive.google.c...
You can reach me at [e-mail] if you want to get in touch with me.
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Thanks for watching, and I hope you found this video interesting.

[@WorkOnP38]

Plenum air filter drawings added to the description

[@khndenmark]

Is is so nice that you have started again to upload videos, thank you

[@WorkOnP38]

Hi, yeah sorry about the delay. Health issues, work and life in general got in the way :) I've felt bad for not being able to add any new content in a while. Thanks for watching!

[@rubenesquivel7350]

Thank you! I thought I had the Rover studyed .sure didn't know the sponge had to be replaced.

[@paulpieters8355]

hello,i ahave a synergy box on my p38 and only have a short power band between 2200 en 2800 rpm above 2800 no power increase

[@soneyliston7902]

I use fishpond filter its almost the same stuff, but a lot cheaper, and seems to last longer as well

[@WorkOnP38]

Great tip, Soney! Thanks for watching. I'll make some measurements of the filter and also put up in the description in case someone wants to fabricate their own.

[@conorguinan990]

Hi I just bought a chip from vector tuning and it requires soldering 6 cables into ecu. Would this be a difficult installation in your opinion? Thank.

[@sebczajna700]

Hi I have still water leakage by the right kabin filter. I tryied to sealing the cover of filter by any effect. Do You know other solution or reason water leakage in this place?

[@WorkOnP38]

Hi Seb, I though I'd made a video about my water leak problems, but I can't find out which one it was now. Anyways, there can be leaks from the screws holding the plenum cover. And also leaks from the whole plastic cover around the cabin filters (not just the lid). Also under the cabin filters theres a plastic bowl that can be a source of leaks for water coming in through the plenum air filter opening (middle below the windscreen). If you remove all the covers it's pretty easy to see what I mean and add silicone or something else to prevent water leaks. Also Gordon Wedman provided some good tips in video # 47 about leaks from the top of the windscreen. And then there is the sunroof and especially the front drains that can be a source of leak. Good luck!

[@mrsmith6316]

Good morning, I did my plenum in spring this year. Watch the lower clips. They are brittle with age and unobtainable now. I've had to resort to small self tapping screws.

[@WorkOnP38]

Thanks for the good tips. My screws were partially rusted away but I saved all the clips. I also have a few extra I obtained a while back. Another tip I'd add is to add a dab of silicone or sealant before installing the screws to avoid any water ingress. Thanks again for the positive contributions and for watching my videos.

[@mrsmith6316]

@@WorkOnP38 My pleasure, your videos are great. We are both victims of the very able P38's!

[@narcofreccia]

Hello there again, I keep on asking questions on your channel. ahah. Followed your video and installed the ronbox on my 1997 p38. My engine was rebored and now has around 30K on it. It wasn't a slow P38 compared to others and after the ronbox installation i've seen an improvement on torque that felt great. I Kept driving the car and now the clutch slips a little if you really floor it. Have you had the same issue? Also do you know what could fix this? (The clutch was re-done with the engine) Should i install a bigger one?

[@WorkOnP38]

HI Andrea. Is it a manual transmission? Anyways, I'm not sure if a bigger clutch would help. I would imagine it would, but I'm not sure. Mine are automatics (both of them) and don't have a slip problem. Well, one has sometimes, but that was after hauling a caravan and a few overheating issues that wore out the clutch bands on the 3rd gear. Thanks for watching.

[@klodjanlohja9490]

Hi there. Did the ronbox helped with hot staring issues on the position 4 that you put on.? Great video

[@WorkOnP38]

Hi Klodjan. The Ronbox will help with hot-start issues if the fuel pump is worn. Which setting has the hot-start fix enabled or not I cannot tell of the top of my head. The instructions that come with the Ronbox will tell you which setting has the feature on and off. Thanks for watching!

[@amirankimeridze2678]

Thank you very much for videos. Does RonBox gives RR difference in power or fuel consumption? Can you write in a few sentence?

[@WorkOnP38]

Hi and thanks for watching Amiran. Yes, you notice a difference in power and also fuel consumption does drop a little bit. My black P38 has had the Ronbox for about 3 years and average 1.09 liters pr. 10 km. That's including towing a 1500kg caravan last summer and a lot of short city driving the last year. Compared the green P38 averaged 1.15 liters pr. 10 km over the last year. Not a huge difference, but if you exclude the caravan towing I'd say perhaps 10% fuel saving. I think the chip boost power around 10-15% as well, and you notice a bit more torque lower down. Note that the turbos on these are a bit slow to build pressure. But it's easier to keep the P38 in overdrive above 70km/h with the tuning chip. Less down-shifting. I feel it's a great value for money and am really happy with having tuned both P38s now. The Ronbox is also adjustable which is nice.

[@amirankimeridze2678]

Thank you and wish you to be healthy and wealthy

[@peterbradley6202]

What the best settings for that Ronbox?

[@WorkOnP38]

Hi Peter, and thanks for watching. It's kinda hard to suggest a best setting. It depends a bit. If you tow, do a lot of high-way driving or city driving. I would try out the various settings and see what fits your driving style the best. I personally have more or less landed on a mid-tune with extra boost. I think it's setting 5 or 6 on the older variant. On the newer model I installed here I'm using setting 4 at the moment. Some recommend not using the highest setting as a daily tune to avoid any extra wear on the engine and transmission.

[@peterbradley4916]

@@WorkOnP38 ok. Will av a play around with the settings.

[@chrisgreenwood271]

What did you think of the tuning chip ?

[@WorkOnP38]

Hi, it'll never make the diesels quick. But it does make them more drivable I feel. There's more low-end torque and a bit more power delivery when you need it. Just enough to make it not shift so much and be able to keep speed up hills. For the money and ease of installation I find them worth it and have them in both my P38s. Thanks for watching!

[@chrisgreenwood271]

Work On P38 having driven one with and one without, I did find a noticeable difference on the p38 with one fitted. Mine came with a chip unit installed, different make to yours appears to be full plug and play, seen them for sale in the U.K. around the £400 mark 😳