So we plan to drive the Range Rover to goodwood at the end of the month. I've done a few local trips of around 80 miles and thus far it seems fine. Theres a slight drone on lifting off the throttle, and a bit of vibration at certain road speeds that i'd like to sort out, i guess i'll start with wheel balancing.

Before we go theres some bits i want to get sorted out, like getting the LPG working! and fixing the shonky track rod end, but those are in hand and i mostly know what i'm doing there, hopefully get onto that this weekend.

However the two bits i'm not sure about are the cruise control and aircon. Neither are critical ofcourse, but both will hugely transform comfort levels on a long trip, AC especially if its hot!

Are there any common faults with either that i should look at?

I scanned the HEVAC with nanocom a while back and i'm sure there was a fault code for low pressure, though i cant actually remember (i'll scan again later). I dont think theres any way to scan the Cruise control system though is there?

When i get the alignment sorted i plan to ask the garage to attempt to gas up the AC system. Which i guess will either work, or find a huge leak... The AC condenser behind the grill looks pretty corroded, but i dunno if it will actually be leaking or if it just looks rough!

The cruise control system i've had something similar in an older Audi, and remember they were a pig to diagnose as there was no diagnostics and about a million different things that went wrong with them. The ECU's also packed up, and the P38 ECU looks pretty similar to the one used on the Audi so its probably the same boat. I remember for the Audi someone wrote a bit of a guide showing various things to probe, which attempted to narrow down where the issue was. Is there something similar for the P38?

Cheers
Kev

Remove the slam panel that covers the radiator etc and check the top left corner of the AC condenser - you'll probably find it badly corroded and possibly with a hole in it. The block of foam that sits on it traps water, and the combination of a steel end plate and aluminium core doesn't help.

The replacements I've seen don't have the steel bracket all the way up to the top of the condenser, and I then remove the foam blocks to get rid of the water trap.

The dryer will need replacing too as the system will have been open to atmosphere for some time rendering the desiccant in it of no use.

As for the cruise control - have you checked the vacuum pipes? The ECUs did seem a bit problematic on earlier ones, though the usual cause is a split vacuum hose.

When you take it in to get the AC re-gassed the first thing every place I've ever been to has done has been to pressurise it with Nitrogen and see if it holds pressure. I had to replace the condenser on mine and also had a leaking hose on the compressor. If it does need a condenser, be very careful as it is easy to shear off the ends leaving you with a lump stuck inside the union.

For the cruise, obviously check the hoses for leaks but if you don't find any there's a test procedure in the RAVE ETM at the end of section B5.

For the AC, the leak tests aren't always trustworthy. I had to replace the condensers in both the P38 and my girlfriends Corsa as they emptied themselves over time but passed a vacuum and pressure leak test when being regassed. I'd get them filled and find they no longer worked a few weeks down the line.

If any part of the condenser looks like it might be leaking, it probably is and I'd replace it. As Sloth mentioned, check the O/S top corner - that's where mine went.

One of my pipes got seized on the old condenser and stripped a bunch of the threads in the connector. There were a few threads that still looked good and as I didn't have another pipe to replace it with I just did back up. I seem to have gotten lucky - it's held pressure for over a year a now and is still going strong.

I got my AC parts for both cars from here: https://www.autoairconparts.co.uk/. The prices seemed good, 2 year warranty and quick delivery.

I did the receiver drier at the same time as it's easily accessible while doing the condenser.

On my first P38, I had the hole in the condenser, though again it still lost gas after replacing that. It turned out the suction line (the fatter of the two solid pipes) had a pin hole leak where it is pushed up against the foam on the firewall. Under a nitrogen test it nearly went undetected until the soapy water soaked down into the foam a bit, and bubbles started slowly appearing around it.

Another water trap. The suction line gets cold and condensation builds on it. The foam gets damp and over time, the pipe corroded through.

As addition of the above, pay attention to the lube oil still present in the system. After a seized compressor of my former CLK I became very keen on that, if you don't know how many 'refills' a system has had it is likely that a lot of oil has gone if performed by the 'home mechanic'. In the US they advertise with cans of refrigerant from the supermarket, throw it in and you're done, at least for this summer (or less). There is more to it, the A/C system is very dedicated summer and winter, it should be maintained by a pro, or at least with the intentions of a pro.
Here is page 1175 from Rave that explains how much oil should be added when a certain component has been replaced:

Not fancying mail order on such a relatively delicate component and wanting the security of local purchase for easy return if it wasn't up to snuff I paid the extra and got a Hella "OEM" condenser from EuroCar Parts. Possibly not the best move as brackets didn't line up properly making it a bear to fit. Worked in the end tho' so worth the effort.

Drier unions on mine were immobile until I heated them up. Should have shifted the air suspension pipe first as I melted a small hole in it and let the gremlins in. Very difficult to see whats going on in that area hence the big boo-boo. Thin wall alloy union nuts are very easily distorted so leaning on the spanners or mole gripping is not effective. Restricted space meant I need three spanners out of my collection to undo the unions as the various bends and angles weren't quite right. Finally christened the stubby combination set I picked up "that will be useful" 20 odd years back. If only there had been about 10 degrees more offset angle on the open end that one spanner would have done it all.

Clive

In this area I go to a chain of garages called Charlie Brown's for AC refills, they charge £50 which includes gas and fluid drain, vac test, refill with correct quantity of oil (supposedly) and refill with correct amount of gas (supposedly). If for any reason the aircon doesn't work following their procedure or if the AC vent temp isn't at least a degree colder following the procedure there's no charge, even if it fails the vac test. I say supposedly because in theory they can just enter the reg or make/model of car into the machine and it supposedly knows how much oil and gas to put in but the machine seems set to short-charge... I watch what's going on to make sure the figures on the machine match what it says on the plate on the car and get them to manually enter the correct figures on the machine if they don't match.

I've also got one of those DIY AC charging kits from Halfords, works out cheaper if aircon is working just not as could as it should be (so just doing a top-up) but would need a couple of canisters (bit cheaper on exchange but still expensive) to charge most vehicle AC systems from nearly empty. The charge canisters contain oil but getting oil charge correct is guestimation using this method - Charge with canister upside down and the oil goes in, charge with canister right way up and only gas goes in, in theory... The pressure gauge on these kits is handy for DIY AC diagnostics, can give insight into whether filling with a bit more gas would be beneficial etc.

Simon

Clive603 wrote:

Restricted space meant I need three spanners out of my collection to undo the unions as the various bends and angles weren't quite right. Finally christened the stubby combination set I picked up "that will be useful" 20 odd years back. If only there had been about 10 degrees more offset angle on the open end that one spanner would have done it all.

Clive

Cut the end of the spanner off and re-weld it with the extra 10degrees... Kind of thing I do fairly often mate ;-) Tools are there to serve a purpose and if they can be adapted to suit purpose better, why not. One of the reasons I don't buy snap-on lol..

Simon

I just take them to Kwik Fit. Guaranteed 10% improvement for £49 or your money back. The one near me is a new building with pot plants, coffee, and all the trimmings I never get from the motor trade because my newest vehicle is an 01 :)
I wouldn't use them for anything else, mind.
They did my Jeep two or maybe three years ago, time to get it done again methinks!

yeh that was the plan, they're just round the corner and i'll get them to do the tracking once ive replaced the track rod anyway.

I had a look today with the nanocom and there was a few codes:

https://www.dropbox.com/s/g52xbl3l4bbp2em/2017-06-05%2020_40_33-2017-06-05%2013.15.28.jpg%20%E2%80%8E-%20Photos.png?dl=0

https://www.dropbox.com/s/lt9son3rq17jfn8/2017-06-05%2020_40_22-2017-06-05%2013.15.23.jpg%20%E2%80%8E-%20Photos.png?dl=0

https://www.dropbox.com/s/vlqc9drz1a4dshl/2017-06-05%2020_40_10-2017-06-05%2013.15.16.jpg%20%E2%80%8E-%20Photos.png?dl=0

https://www.dropbox.com/s/2wo4w6md9o615er/2017-06-05%2020_39_57-2017-06-05%2013.15.09.jpg%20%E2%80%8E-%20Photos.png?dl=0

https://www.dropbox.com/s/g0ndesmgyjqclt2/2017-06-05%2020_39_25-2017-06-05%2013.15.00.jpg%20%E2%80%8E-%20Photos.png?dl=0

I think the compressor clutch code indicates that the pressure switch is open?

All three blend motors are iffy and there's a problem with the compressor clutch. It may be that it is down to a lack of refrigerant or that the HEVAC can't detect the load of the clutch. The latter happens if someone tries fitting a relay to power the compressor rather than direct from the HEVAC (I know as I tried it.....).

I presume the blend motors are a dash out job? If so thats not happening any time soon :P

Looking at the wiring diagram, the clutch is in series with the pressure switch, so the switch being open will certainly give that fault code.

I think the blend motors are possible without taking the dash out if you're double jointed. It's the heater matrix which is definitely dash-out time. Mine was leaking so we (well, Marty) did the whole lot at once.

You can get at both the drivers side ones by taking the instrument panel out but you will need a small ratchet No 2 Pozidrive screw bit. Passenger one can be got at by dropping the glovebox out. Both are fiddly but there is no need to take the dash out. Have a look at this http://www.rangerovers.net/repairdetails/blendmotor.html

I had a quick look in RAVE at the blend motors this morning after seeing this thread. It says that cars with just a heater can be done with the dash in place but cars with A/C have to have the dash removed. I was amazed to learn that some cars didn't get A/C! I don't think I've ever seen one.

Perhaps the suggestion of removing the dash in RAVE was an attempt to increase the chargeable hours in the dealership :P

It probably was as I've heard that these days they are only quoting a couple of hours to do the job. There were a very few early base spec cars (usually diesels) that didn't get AC but almost all did. I did the blend motors on mine not long after I got it and couldn't see what all the fuss was about, I just took the side panel off the centre console and got to them from there. Then realised that as a special order for Plod, mine doesn't have the ducts down the sides to feed the rear vents (no point in having vents when the rear is going to be full of traffic cones). Did the heater O rings on a LHD car a couple of days ago and the duct put up a bit of a fight, but gave in eventually. With that out you can see the blend motors from the side but with it still in place you do need to go in from above (which on a LHD car would involve removing the passenger air bag).

Spent a good bit of time on the P38 this weekend. Weather was crap so lots of rain dodging.

Felt like lots of partially completed jobs, but progress nonetheless.

Got the steering track rod swapped out, but still need to take it and get the tracking done.

Got the LPG injectors changed as per the other thread, but not working properly.

Did some testing on the cruise control. With the pipe to the cabin blocked off, i powered the pump and ensured the pump and solenoid was working properly. All fine. Connected the cabin pipe back on and it stopped pulling a vacuum. Disconnected the pipe from the switch on the brake pedal and blocked the end and it still wouldnt pull a vacuum, so i've ordered a new length of hose and will resume testing once i get that replaced. At least i know the pump and diaphram are good.

Inspected the AC condenser, and it looked ok. A bit crusty, but no obvious corrosion at the top edges, so i hope that'll just need gas. Will find out when it goes in for alignment etc.

Dropped the engine oil and replaced with 5w40 (it had 5w30 in it that i'd put in as a bit of a flush). No issues there.

Decided to have a look at the Autobox, so dropped the sump off that, and put a new filter in and refilled with oil. Unfortunately i'm about a litre short, did the level check with the engine running and the level was just on the pip on the bottom of the dipstick. So need to get some more oil for that!

Dropped the oil out the front and rear diffs and refilled with EP90. No issues there.

I wanted to do the transfer case as well but obviously the lack of ATF knocked that on the head.

All in all a reasonable bit of progress, just annoying that theres a few things that arent finished!

Aragorn wrote:

Decided to have a look at the Autobox, so dropped the sump off that, and put a new filter in and refilled with oil. Unfortunately i'm about a litre short, did the level check with the engine running and the level was just on the pip on the bottom of the dipstick. So need to get some more oil for that!

I found that the difference between the bottom pip and the top one is less than half a litre. I changed mine and it was just showing on the dipstick so I bunged a litre in and that took it to way over the max. Ended up with the excess being blown out of the breather.

When you pull the cruise control pipe out, you'll probably find a split where it passes through the grommet in the firewall. My silver one split there - I found blowing on it from the actuator end lead to a hissing from behind the engine.

Replacing with silicone, hopefully? :) Just replaced the hose on the red one seeing as its dead easy with no engine in the bay, and found while it was working (having replaced the two bits at the actuator end a while ago), it wouldn't have lasted much longer - a nice split forming at the grommet too.