Evening Everyone,

There is a question that has been burning in the back of my mind and it's one that I really would like to know what your thoughts are.

I own a 2006 E53 with the 3.0L Straight 6, and just over 100,000 miles on it, which I am the second owner; I have taken care of this car at every turn since it came to be in my possession. A little while ago I came across a 2005 Land Rover LR3 (Discovery 3) which has the BMW 4.4L V8 that had 180,000 miles. I parked the E53 to drive the LR3 as a daily and to do some much needed work on the E53. All the work is finished on it now, but with how gas prices have been... I've just been letting it sit.

I will admit I put some mid-grade 89 in the LR3 with some purple power octane boost or STP octane boost... but it was clear that the engine didn't like that and it sounded like the engine had bronchitis with no power at all. I ran some seafoam through it and ran a tank of 93 premium through the LR3 and it's getting back to where it was before… sort of. The passenger front strut on the LR3 would not hold air it was causing the compressor to go into protect mode so I parked it until I could allocate funds to replace it… ontop of that… after a downstream O2 sensor failure and sensor reset via GAAP the MPG has been absolutely awful (around 5-7MPG) so with all of that it was parked and I picked up something else in the meantime until I can get some heading on these.

Right now I am driving a 2017 Taurus Police Interceptor which takes bottom of the barrel E85 which around where I am right now I can get for 2.30/Gallon.. or 1.30/Gallon from Meijer... which is great... but Premium is still 3.99-4.44/Gallon... So on an E53 or LR3 top off, we're looking at least double the cost over 100$ in fuel every two weeks. Or every week with how the LR3 was behaving.

E53 has only ever had premium... and shaking the cobwebs off it this evening before Winter sets in reminded me how nice it rides by comparison to my Interceptor, but I don't want to harm the engine and can't really afford the 1.50-1.90/Gallon up-charge right now. Same with the LR3, I would love to drive it again once I get the strut repaired, but what is a man to do?

How do you keep your engines happy with these crazy gas prices? Or are a lot of them sitting right now?

 

Incorrect, the L322 had the BMW 4.4, the D3/LR3 has the Jaguar 4.4. Oh and for economy, buy a diesel, my 08 TDV6 D3 does up to 30mpg even with the added extra's i have on it.

 

I buy premium only. In central Texas I’m paying 3.30ish right now

 

I pay about 2 euro per liter or converted to US dollars and US liquid gallons……….. $8.16.

You’ll be fine, don’t worry. 😂

 

With gas prices there's no winning, you just delay losing.

 

All I can say is maintenance is key..... period. If the spark plugs are old, MAF sensor dying (or dirty), air filter dirty, transmission fluid old, diff fluids old, brakes possibly binding and thus dragging, fuel injectors restricted, etc, etc, etc.... All of that and more contributes to fuel economy woes. I guess the only good thing is at least fuel prices are back inline to were they should be so not sure what you mean by crazy prices. Pre-covid my trips were budgeted at $3.20/gal for premium. That was five years ago. So that would be $3.87 today.

You need to do more than replace one downstream O2 sensor - which in itself is odd since they rarely fail. After all, they are down stream and in the cleaner air after the cats. I replaced mine at 200k miles simply because I wanted to. Also they only monitor cats. So if they throw a code, that generally means a bad cat. And a bad cat would certainly cause issues.

I myself run premium when I can. But I have taken trips out west in the US were mid-grade is the best octane I can get. The truck runs fine on it less noticeable acceleration and my milage goes down. So I try not to hammer the engine hard. But the flip-side is while economy goes down, the cost saving of the fuel usually puts me ahead. As a daily drive though, on premium, I get about 16mpg around town and can hit 20mph highway but I "plan" for 18mpg highway.

Start with the simple obvious. Take the LR3 for a spin and make sure none of the brake are hotter than the other. Brake drag can really impact fuel economy, its like towing a trailer. Then clean the MAF and check the air filter. Maybe replace spark plugs, have they ever been done? When I did my transmission fluid change, I gained a couple MPG.

 

For half of its run anyways.

03-05 L322 had the awful BMW 4.4, but 06-09 had the same Jag 4.4 as the LR3 and RR Sport. (09-12 had the timing chain grenade 5.0)