Hi everyone,
I'm experiencing a drop in performances after my Defender is warmed up (about 15 min. - 30 min. drive). I have noticed that it feels anemic accelerating from the line and driving around.
It is a 2020 Defender 110 HSE P400 with about 20,000 miles, an oil change was done 600 miles ago.
The sluggishness is not very noticeable to other people driving my Defender but it is to me. When accelerating from a line, it takes me over 11 seconds to get to 60 MPH (no A/C, fridge, fan etc.) as a comparison, I measured around 6seconds on a fresh start....
It only happens after I drive it for a little while so I tend to think it is a sensor issue that adjusts the mix (MAP, oxygen sensor or?)

I recently had an issue with a strange grinning/rattling noise. Our local dealer's mechanic was able to pin it to me using 87 octane, and after replacing the fuel, it has been 98% better.
Based on that I'm suspicious that something is fouled in the fuel system but not sure how to prove it since there is no warning light on....

Can anyone provide any insights? it is really a bummer driving a P400 that feels weaker than a 4 cylinders....

Thanks,

Roy

 

Does this only happen after a few 18th-century dance songs have played, or do you see it after a few soft rock or disco numbers as well?

 

I have a 2022 D90 with the P400, I have only used quality 93 octane and had my first oil change at the dealer with 3200 miles on the car last week. My 90 is fast as hell (for a heavy toaster oven) LOL

 

If you can afford a Defender you can afford high octane top tier gas.

My neighbor always put the cheapest regular gas in her LR4 and had constant check engine lights, had to replace fuel filters and injectors. I used 93 octane top tier gas in our LR4 and was still on the original fuel filters and injectors after 160K miles. Never had the check engine light come on.

 

so use top tier gas or add cleaning additives on a regular basis you say?

I have met a number of people who have used different octane levels based on a varying amount of theories. Sticking to what is recommended by the manufacture seems best practice.

 

Land Rover states "premium gas recommended" - They should use the word required....

 

If the check engine light would fire up, I would at least be able to take it to the dealer and they can work off of the fault code.
It's not about the money, the sticker on the gas cap states "premium gas recommended", it should work fine with regular gas.

 

Defender 2020:

I fear your use of 87 octane for an extended period may be the cause of your concern.

I suggest you look at this video (SCROLL DOWN TO THE END OF THE LINK), beginning at 5:45 to the end. IT IS VERY COMPELLING AND HELPFUL.

I hope it helps you. https://www.mcnallyinstitute.com/doe...e-your-engine/

I have only ever used 93 octane from Mobil/Shell/Exxon on my 93 octane engines. Similar to what was stated by Paul, it has been cheap and effective insurance.

Enjoy!

 

I can understand your point -- if it's going to screw up the motor then it shouldn't be allowed at all.

The thing is, though, it takes time and a lot of low-octane gas to do the harm. If you run a tank of it the computer will just pull enough timing to keep from detonating and you will suffer reduced power and poorer emissions for that tank, then all should be fine. So if they put Required or other language that seemed to forbid the use of 87, then somebody who found themselves unable to get access to 93 for some reason would sit waiting for a towtruck to haul them to a station with 93 rather than just using 5 gallons of 87 from the nearest farmer's lawn-mower stash to get to the nearest station.

So I suppose JLR thought the best compromise was to put "Recommended", hoping the owner who saw that and didn't want to follow the recommendation would at least do a deeper dive into the owners manual or the internet or the dealership service department or somewhere to find out just why it's recommended.

 

Exactly - It should run fine and if it's not there is a issue. Not all fault codes throw CELs. If this were mine I'd have the data ready and visit the dealer. IMO Somethings wrong

Matt