what type of gas car X5 use? (gas is too expensive)

[mikey19]

hi
so yeah my mom has a 2002 X5 4.4i
i was wondering if her car can use 87 grade gasoline and it would not damage the engine.
the manual says that 91 minimum but did not mention what happens if one goes below that.

on my M3 manual, it actually states that going below 91 will result in engine damage.

im wondering b/c there is this gas shortage in Atl region and 93 is just hard to find. since her car has a normal V8 engine, wouldn't 87 octane gas be okay? I dont think she cars about performance and her car is pretty old.

thanks

[Deda]

well if manual says 91 is minimum then it is...yes you can drive it,but you will make damage to you engine eventualy.

[crooked I]

i use 87 and 89 all the time....hasn't harmed my engine

[mikey19]

i guess what am i asking is that for those who have used 87 in your bmw engines, is there any negative effects besides lower power output.

my family is not looking to have this car for another 20 years, so keeping the engine running for that long is not the top priority.

it is just impossible to find 93 gas around atlanta these days...and the X5 4.4 gets like 14 mpg around town

i had a friend in college who would regularly use 87 and would fill up with 93 every 5th tank with his G35; and that is on a pretty high performance V6.

[branko]

Originally Posted by mikey19

is there any negative effects besides lower power output.

consumption will go up and most likely the engine will also consume more oil..

[chuck92103]

You don't save any money using lower octane fuel since the vehicle will be less fuel efficient. The engine won't perform optimally.

If you are using cheap gas you are not saving any money nor are you enjoying the car to its fullest.

[docrecruiter33]

using the lower grade gas will gunk your engine. not worth it! if you want to use lower grade gas, trade in your bmw. just a thought.

[Grover432]

I don't think you will do any damage. The octane rating is an AKI rating (anti knock index). With computer in you 4.4 , it will sense knock and adjust timing to prevent it. The rsult is poorer fuel economy an dreduced performance. But, if you can't find premium fuel, I don't think you have to park it in the driveway out of fear you'll ruin the engine. I think the extra gunk comment, is well, just bunk!

[rsmamg]

ive been using 87 on my 03 x5 and after 75k miles, no problems at all.

[cncmastr]

Originally Posted by rsmamg

ive been using 87 on my 03 x5 and after 75k miles, no problems at all.

Why?!!!?!?!!

Essentially, you're spending more money at the pump than if you were to just buy 91 gas. Why you ask? because your engine has to retard the ignition timings, the vehicle consumes more fuel, resulting in lower output, increased consumption and lower gas mileage.

How much money are you actually saving? $.10 a gallon? What is that a tank, $1.60? WOW!!

[cncmastr]

Originally Posted by gary_g

i use 87 and 89 all the time....hasn't harmed my engine

ugh! Go you! You're really sticking it to the man.

[eurotechnik]

I highly suggest not using 87 or 89 octane. For those who say they use it and have not had any problems, be prepared for some down the line. I work at a BMW dealership as a Warraty Manager, there are some horror stories when a customer uses 87 or 89 octane. Save a couple cents here and there but you'll utlimately pay the price.

[ad78]

really? you can use 89. just it will lessen the car performance.

[archwerks]

The world needs more penny wise pound fuelish people. let them use canola oil!

[crooked I]

just did a quick google search, looks like your gas prices are around $2.40 a gallon (atlanta), im in canada and i jus payed $1.15 per litre for 91, which is like $4.23 a gallon?

if you buy a BMW, put in the right gas, there is a reason why they tell you to put 91 octane. if you cant do that then get something that can take 89 octane and get's better fuel mileage.

[bayerischeperformance]

people dont really understand what the differences are between different octanes. It used to be detergents were different now those are standard across the board.

However your car's compression ratio is around 10.5:1 if i remember correctly. With a lower compression engine say 8:1 you can use a lower octane fuel due to less heat being created. Since a higher octane fuel doesn't ignite until later in the compression cycle it will withstand a higher temperature. Putting a lower octane fuel in your higher compression engine can cause knock and detonation, yes you have knock sensors though they cant always catch it in time and you could blow a rod thru the block. Unlikely but ive seen it happen.

the main thing you'll run into like others have said is decreased fuel milage. You'll get more carbon build up as in over time your motor will fill with carbon deposits(see image below) Now at first ya carbon deposits are normal and can be ok to an extent though after time they will build up to an extent of raising your compression ratio and making things completely different




So summary ya you might be saving a couple bucks cause every time you are buying gas though you are spending more since gas milage is decreased, over time causing more harm than good, and if you cant afford it dont drive it