Hey Everyone,
I have a 22 P300 90, I just got back from the UK seeing my family for christmas and when I started my car it had an engine check light on.
Its Sunday before NYE and everything's closed so I went to Autozone to use the free engine check service and borrow there OBD reader, turns out the code is a P0128 code.
Engine has not been overheating and has been sitting comfortably just under the halfway mark yesterday when I needed to drive, so I am assuming its the o ring and not the whole Tstat but impossible to know I guess?
The issue is I have a NYE trip planned tomorrow and need to drive 2 hours up state, the LR garage opens at 9am and I am going to try get it seen to in the AM but I am doubtful, am I crazy to do the drive if the car isn't overheating?
I just passed 50K miles so conscious my warranty is also up.
Thanks!
J

 

The P0128 means that it is not warming up fast enough. It's not over heating. Think under heating.

Check your coolant level. That's going to be your biggest risk and easiest fix. With the engine relatively cool, check the level. That would be your easiest, best hope. If that does it, make sure you get the RIGHT coolant and then later make sure you find out why you lost it.

Other causes of the P0128 are going to be:
- Stuck thermostat. You'll likely need a replacement. I've changed many of these but no idea where the Defender's is without looking. Changed many of these in Mini Coopers and they area. PAIN. Hopefully the Defender is easier to get to. I recommend pricing an independent shop than the Dealer. If this is your problem, it will mainly be a fuel efficiency problem until fixed. Long term like this could cause problems in your oil, but over a few days - I wouldn't worry about it (if this is the problem!).
- Faulty temperature sensor. Again, without looking, no idea where it is and how hard. This can be piddly and tough to find. If you have enough coolant, this is likely another efficiency problem to your fuel economy over the short term.
- Cooling fan stays on. There's a fault somewhere and it is cooling down to much. While this is a cause of the P0128, I'm a doubter on this one.

Good luck and post what you find when you get it somewhere.

 

Thank you for the response,
I took it LR Manhattan today on my way out of the city, they were actually really helpful, and eager to help under time pressure, they saw the car right away and did a diagnostics/health check etc. and confirmed the code, they did a coolant pressure test which came back fine.
They then told me I needed a new Thermostat and potentially some hoses, and then quoted me $3200 which made my eyes bleed.
Upon asking how in any world changing a thermostat could be that much, they said it was a 7 hour job, on a $375 an hour labour rate.
They told me it was safe to drive as it wasn't overheating and that I could come back and get the work done as I needed to get upstate today.

On the drive up the car kept a really low temp and basically bounced between 1/4 and a 1/2 on the temp gauge, seemed to get cooler the faster I went.
I also noticed that my AC wasn't blowing very strong, and it definitely felt like i was lacking a little acceleration that I usually have.
My understanding of a thermostat was that it essentially hits a temperature thats too hot then opens up and lets liquid through to cool down and once its at the right temp it closes back up again, excuse my ignorance, but how does a faulty one keep the engine temp lower? is it just stuck open?

It left me with a few questions, I have changed thermostats on some of my first cars, fully mechanical cars but it never took more than an hour, and looking online it seems like this is an hour to two hour job max? how do they decide its a 7 hour job?
The labour rate is obviously insane, so I am assuming as I am out of warranty the best move here is to go independent? I spoke to British auto works in the bronx who used to do my 1989 RR, he thinks he can do it cheaper, but also said I should consider changing my water pump as I am at 52K miles, I feel like this is turning into a wallet fishing expedition and not a fun one after Christmas and only having owned the car for 10 months. sigh. My old Macan GTS I had for 3 years up to 80K miles and never spent a penny on it.
Is this the beginning of a lot of problems with this car, or just a one off?

 

The Ingenium engines are very solid, but things happen. JLR products are notorious for coolant pipes going bad and issues with thermostats, but it is not as common to see this on these newer engines. Nothing JLR makes is as reliable and flawless as a Porsche. I have a 2023 Macan S in addition to my Defender, and while I've had it for over two years, I only have 13k miles and it has been flawless. I beat the crap out of it too - I've taken it on track, I do around 5-6 autocross events every year and I drive it hard on the street and it doesn't miss a beat.

That being said, my 2021 110 P300 has been problem-free other than the DRLs going bad, the heated steering wheel going bad and the ECU for the fuel pump went bad a month after I took delivery. I might have a tiny leak in the auxiliary radiator, but I'm having that looked at next week before my warranty expires on the 23rd.

 

Seven hours? I can certainly believe it. I was looking at a workshop manual (TOPIX) for the P400 last night out of curiosity. I suspect the P300 is pretty much the same. The water pump is on the left side of the engine (driver's side for US spec) and pretty low. I think the proscribed way is to come from the top and removing it is step 47 after removing a LOT of other stuff. Reading the split coolant system, it is pretty complex to maintain a fine balance of coolant. Yes, when a thermostat is stuck open it just lets coolant go thru at whatever maximal rate it is stuck to. NY these days is a lot cooler than the summer in Phoenix which it can handle. So, I suspect your engine won't warm up because it is w.o.t.




My thoughts on your Q's:

- Yes, I believe it is a 7 hour job. That is their "spec" for the job. Younger techs may take longer, seasoned pro's shorter. Me, I think it would take me a 3 day weekend. I would rather change the header gasket again on the neighbor's Ford Probe. Living in NYC, if you want a lesser quote, try to find an independent Land Rover shop. I'm sure some are around (EDIT: Reread you're already there). The hoses are because they are sure to tear some stuff up removing them and want you prepared for the bill. BTW - If they come up from the bottom, I suspect it will take over an hour just to take off the skid plate, felt panels and other cladding down there. There's a LOT.
- Manhattan. JLR Tech Rates. Yeah, I could believe that rate.
- Yes, go independent. Rent a car and drop the Defender off.
- Agree with the Indie. If they're already in there, I would consider changing the water pump. Depends on the cost.

Good luck!

 

Do you have the digital workshop manual ?. I also like to make $ 375.00 an hour😀
You mentioned some wrenching experience with thermostats before, accept this new challenge. We will help.

 

Each step in the attached pdf is likely a rabbit hole of removal of other stuff. The shop manual is a great resource.

Looks doable and worth doing to save the $3500 in labor but to each their own.

Brute force, basic tools, patience and a few beers are in order.

Each clip and electrical connector is a little puzzle unto itself on these engines. If the Defender was an animal, the comparable location of the thermostat would be 8" up the ileum.

 

As @Defendit.. points out - if you want to tackle this, grab the workshop manual. There's a copy floating around the forum. I have the P400 version, you'll need the P300 version. @GavinC gave a great service by targeting section 303-03C "Electric Thermostat" Removal & Installation. As he states, this is doable. One thing to note is that these often turn into a spaghetti game of referenced sections. 303-03C will lead you to 412-01 which details removing the AC Compressor and it in turn leads you to 412-00 which is AC System evacuation and recovery. You may be good (or lucky, either works) and able to work around disconnecting the AC system. Then you won't have to recover or replace the AC.

At that point, I gave up on tracking down the subtasks and decided to eagerly await the results of your journey. Me: my 3 day estimate of me doing it myself went out the window with "General equipment: Air conditioning system refrigerant recovery / recharging stations". Some might just vent it out, but for me that's a nope. Not judging anyone's techniques, I'm just outlining my skills boundary. I agree with GavinC - this one is going to go deep into a dark body cavity. Some folks enjoy spelunking!

 

I just posted the P400 bit of info. Sorry Probably different on P300.

Dealing with A/C systems would be completely new to me. I didn't look into the weeds on the instructions. Probably all sorts of extra stuff to get. Probably beyond my meager gibbon-skillset. What a PITA.

I'd probably get the instructions all laid out, look at it for a bit before getting the parts and finding a good independent garage to give me a quote. Seems like too much opportunity to screw things up.

 

Thought I would do a little update on this thread as I got my car back today.
I priced it out with independent, and then re approached LR Manhattan and asked if they wanted to help on price as I would rather have it done through them etc.
I have to say that Catherine in services that works there was absolutely incredible to deal with, I know we do not hear about many positive LR dealer stories but she really went out of her way to help me out, they helped on price (ended up being the same as independent) as I was only 800 or so miles outside of my warranty. They fixed it incredibly quickly, she was in contact the whole time updating me etc.
What started as a cold shower ended up being a good experience, I was concerned dealing with a dealership in Manhattan would be a nightmare but I have to say I am pleasantly surprised!
Car is back on the road and driving perfectly so far.