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I have a 1990 240DL five on the floor sedan and I have a question concerning fuel octane. My manual states that Volvo recommends the use of an unleaded premium gasoline with an (R+M)/2 rating of 91. The car has 152,000 plus miles on it all while using premium gas. Can I safely use an octane rating of 87 or 89? I have tried 87 and I am currently trying 89 with no noticeable spark knock or performance problems. The service man that services my 240, he is a former volvo dealership mechanic, says that he has never used premium in any of his Volvos. He has always used regular. Also, could there be damage going on from the gas if there is no knocking or performance lag? In my area there is a difference of twenty cents between 87 octane and 93, and a difference of ten cents between 87 octane and 89.
Thanks CJ Hill
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I have put well over 100,000 miles on two 740s with B230F engines and manual transmissions. I have never used anything but 87 octane, and never experienced any kind of fuel related problem.
A couple of months ago, in response to an earlier brickboard post, I tried a tank of 93 octane. I didn't notice any difference at all in the way it drove, nor did mileage improve.
I flogged my previous car mercilessly, I am somewhat gentler with my present one, such that I am getting 29-32 MPG. I see no reason to use any octane higher than 87 in a B230F. B20s are another story--they usually require 92-93 to avoid excessive pinging.
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I've had a few Volvo's in my life...
For the past 20 years I've been using 91-93 octane with
great success. Never had ANY engine problems.
I even use high octane in my mowers and gas blowers.
The higher octane fuels seem to have better detergent
properties and burn cleaner.
If your car has been thriving on higher octane, why change it now.
It just doesn't seem to be worth the 20 c/gal savings.
--
-Cool Volvo- 1982 240 4 Spd OD w/ 246K, 1989 240 5 Spd w/ 237K. Past proud owner of 1966 122, 1968 144, 1970 145, 1972 144, 1980 245
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My vehicle: 88 245A: I have experimented with the three different grades. My wagon does not knock with 87 but there seems to be a slight improvement in performance when I use 89; feels peppier. Can't tell a difference between 89 and 91. Fuel economy is [unscientifically] about the same with all, maybe moderately better with 89 than 87. I am however a firm believer in the "top tier" fuels with additives intended to keep deposits from forming and the emissions and fuel intake system clean.
Best known is Chevron with Tectron; Shell also is a top-tier fuel and depending on where you live there are some local brands that have the additives. Reason I believe in it: All my cars always pass California's stringent smog test. I never have needed to clean injectors or throttle body. It costs a bit more per gallon and I am not a fan of Big Oil but I believe the top tier fuels provide long-term benefits and pays for itself. You can Google "top tier gasoline" to see the brands. GM, BMW and Toyota cooperated in spec'ing the fuel requirement. What's in it for them is they have fewer emission warranty claims when their cars use the fuel.
Fuel prices in Scam Diego this evening at my Chevron station: 87=$2.31; 89=$2.41; 91=$2.51.
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I bought a '90 244 that came with complete records, including a book with all gas purchases logged. They were using premium 93 octane all the time. As soon as I started driving it, I used 87 octane. It will run about 26-27mpg on the highway, but I have a heavy foot and mostly do short trips so I get about 23mpg. It's a 5spd, so it has the rare LH3.1. It runs fine and actually feels faster than my '87 240 5spd felt when it was still stock. But the throttle response is not particularly great. I think the LH systems are not as good as a more modern system would be, but it gets the job done.
In my '87 240, I've change the intake/cam/exhaust and I'm running a fully programmable fuel system with fuel and spark tables that I tune myself. I still use 87 octane, but the car makes a lot more power. The stock system always ran too lean, so power was down. But by tuning the WOT points to be rich so it makes good power, yet tune the cruise points to be lean so it gets good gas mileage, I can do better than the stock LH system in both. On a ~1700 mile round trip this past summer, I logged 28-29mpg on 87 octane on the highway. On some stints I saw as high as 31mpg. With LH2.2, I never got over 25mpg on the highway.
I definitely wouldn't put premium in a car with only 90hp. It's not that sensative, and it won't make that much differece. Instead of lugging up hills, downshift. It can handle the revs...
--
forums.turbobricks.com
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As another benchmark... 1990 5-spd 245, LH 2.4, 93 octane, cruise set at 70mph, never saw less than 32mpg last trip this summer... as high as 34.5mpg on one tank through the higher altitudes.
I think an underestimated factor in the octane question is detergent additives. All else being equal, if you're not pinging, you don't need higher octane... but premium fuels usually have a better detergent package which keeps down carbon build-ups.
For me, I maybe use two tanks of gas/month. At about a buck more per tank, premium is pretty easy for me to justify.
-Ryan
--
--------------------------
Athens, Ohio
1990 245 DL 130k M47, E-codes
1991 745 GL 280k (Girlfriend-mobile)
Buckeye Volvo Club
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Read a fuel article in someones home page here.
It said brand important.
And to try different fuels.
See what works for your car under load.
Formulations vary,winter/summer/region.
The modern engine management systems
will simply use more fuel if octane is insufficient.
My old 71-145 S runs best on 76 or Standard;92 only.
here in Cali. we have 10% corn alchohol which
burns cleaner but produces 10% less milege.
Anything less, the engine is knocking itself
apart and carboning up the head.
Sorry I can't remember where I found the article.
--
White 86-245 DL, M 46, IPD bars & Wagon Overloads,Commando Bumpers,SS Belly Pan & Air Pickup,Straight-Shot EMT Chassis & Tower Braces,Scorpius Alloys,2 Belt No AC Conversion,Black POR-15 No Glare Front End
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posted by
someone claiming to be tjts1
on
Wed Oct 25 07:17 CST 2006 [ RELATED]
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Anything more is just a waste of money. If you do notice any problems running on 87, you'll know there is problem with the engine.
Justin
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I've always used the Middle Grade fuel (89) in my '89 200.
I'm coming close to 300,000 miles on it. Original owner. I don't think you will feel any degradation of power.
--
'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me
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My wife uses 89 always; I use 89, 91 or 93 as the mood strikes me. Our "spare" '90 is driven by another family member with a tighter wallet; I'm sure it gets 87.
I know another Volvo mechanic - Aye Roll hangs out on this board occasionally and I'd trust him to fix anything on a rear drive Volvo. If I recall he uses nothing but 93 octane. He usually owns three rear-drive bricks at any given time.
The deal is, the cars have a knock sensor. As soon as it detects knock, the computer retards the timing so you never hear it, or only for a brief instant. So even with 87 octane you'll likely not hear any knock.
What you will detect is "nothing much happening" when you put your foot into the gas pedal. The retarded timing reduces the power output. If you ever adjusted timing on an older car you must remember how retarding the spark reduces the rpms.
When driving, the knock occurs under heavier engine load - wider throttle, hills, passing, etc. You may not notice it much if you drive on flat roads and never have an urge to step on it. I drive hills at 50-70 mph, sometimes with three adults car pooling in my 245. And every now and then I find a need to pass someone. So I like having the higher octane in there.
--
Sven: '89 245 NA, 951 ECU, open-front airbox, E-fan, 205/65-15's, IPD sways, E-Codes, amber front corner reflectors. Wifemobile '89 245 NA stock. 90 244 NA spare, runs.
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Sven,
If you are using 89 now, can or should you go up to the higher grades? My brick has 160k, I thought in a post I read quite awhile ago, the higher mile cars should go up the the higher grade, but I honestly can't remember when you should start using the higher grade, if you have'nt in the past.
Thanks for your input!
Mavis M
91 245 SE 160k :)
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The simple solution most people use is to run the lowest cost gas that doesn't ping in their car, the way they drive it.
I think the principle behind the suggestion for higher octanes on high-mileage cars is that over time, carbon tends to build up in the upper cylinder surfaces, which causes ping/detonation. The higher octane fuel resists early ignition, so it's a remedy for that problem.
So you could say that higher mileage cars should use higher octane fuel - because they would likely have carbon buildup. Of course, not all high mileage cars have carbon buildup, some low-mileage cars do, and some cars get crummy performance from low octane but you never hear them ping, due to knock sensors and cleverly programmed computers.
The whole business of ping, detonation, carbon, ignition timing and octane can get pretty complex if you try to map it out in detail. And it can be pretty difficult to resist the pat answers offered by well-meaning folks who will tell you too quickly what is happening with your car, when in fact several things are likely happening.
Carbon buildup? There are some remedies, but I don't know any that is low cost, effective and guaranteed trouble-free. You can take the head off and clean everything (expensive).
You can use SeaFoam. It's a doable job for a driveway mechanic but some users have reported problems from it. Others swear by it. My own suspicion is that SeaFoam is likely pretty good for a car with maybe 50-100 K miles. But our bricks have been building up carbon longer than that and when all that stuff gets blown through the system at once, I suspect that load of carbon can make trouble down the line at the oxygen sensor or catalytic converter or such. I never had the guts to try it.
--
Sven: '89 245 NA, 951 ECU, open-front airbox, E-fan, 205/65-15's, IPD sways, E-Codes, amber front corner reflectors. Wifemobile '89 245 NA stock. 90 244 NA spare, runs.
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Let us take a moment to consider the design criteria of these cars.
Economy= 4 cyl ,saftey= somewhat heavy ,durable=good hardware.
4 cyl X heavy =high compression. That is the choice the
Swedish Engineers have made for these cars.
High compression needs high octane to burn at the optimal
moment to produce the maximum power yield.
I work my cars pretty hard, and would not consider anything
but what is recomended by Volvo.
Short trips where the engine is not up to correct operating
temperature is probably the source of most carbon build up
in a modern engine.
The Italian Tune Up that I get after 100 miles on a road trip,
kind of confirms my suspicions.
Different strokes...But my 145-S knows.
--
White 86-245 DL, M 46, IPD bars & Wagon Overloads,Commando Bumpers,SS Belly Pan & Air Pickup,Straight-Shot EMT Chassis & Tower Braces,Scorpius Alloys,2 Belt No AC Conversion,Black POR-15 No Glare Front End
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