Volvo C70 Fuel and Mileage Questions

Claires

Share your actual mileage numbers with other C70 drivers here.

jaspar1

1999 Volvo c70 coupe 27 - 240,000 miles - 27 mpg combined

singaporekid

15 mpg. 6 miles of stop and go. 1999 C70 Convertible.

tsk1

2007 Volvo C70 - with Geartronic - 2218 miles in Europe - 1400+ of which were on the German Autobahn (90-100+ MPH) - 24.7 MPG

dogdokken

2001 C70 Coupe:
17 mpg street, 23 mpg highway

Running on Mobil1

lemenn

At this stage,
32.7 miles/gal with the new C70 D5 turbo diesel engine

johnh7

Maybe this is a stupid question. I realize this car is an "it's ok to use regular but premium may produce better performance" type, but what octane gas are you guys using?
:confuse:

cricket4

I wish someone would answer your question because I would like to know the answer too. My car will be here in a couple of weeks. The Volvo dealer told me that guys in their service dept said that using regular is just as good as using premium that the car will calibrate to whatever gas is used (but to not switch back and forth). I've also heard that not just the octane grade is important but also whether the gas is "dirty" or not... some brands (like Conoco) have "cleaner" gas and don't have as much sediments. This is not as much of a worry since most brands got wise to this and have cleaner gas now. It was a process that they were using. I could be so far off base on this (so feel free to correct me if I'm wrong). I'm going off of opinions that I've heard. Thanks.

tsk1

Having used regular, mid-grade and premium, each for multiple tanks, our 2007 C70, T5 does run fine on either. No pings or delays. It does seem a bit quicker with premium. I do notice about a 1.5-2.0 mile per gallon improvement with premium under what I believe to be the same driving conditions. We will probably lock on either mid-grade or premium.

jtrego

Premium gas will definitely give better gas mileage under most driving conditions...as to performance...I have heard this discussion so many times and from so many different perspectives always with the conclusion that acceleration and performance should be better with premium when the car is taxed out.

In other words, to get the hp that is always quoted by the manufacturer of the engine you have to use high octane. for everyday driving...gas mileage is more affected by "how" you drive. If you are always stomping on the gas or reving to the highest rpm, etc, etc then your gas milelage will stink no matter what grade gas you use. However, under somewhat restrained or normal driving you should see improvement in gas mileage with higer octane...but then you pay for what you get don't you?

I have always noticed the biggest difference with premium on long trips on the highway where you don't have to stop as often with premium.

cricket4

Did a Google search and found a good article at USA Today online. There is a lot of debate about Premium vs. Mid-Grade vs. Regular. I like the quote from the 45-year veteran engineer with Chevron Oil who also sits on the SAE committee regarding his wife's use of low octane. This article has helped me make up my mind. Here it is http://www.usatoday.com/money/autos/2003-07-30-premiumgas_x.htm

johnh7

Great article. My dealer recommends regular by the way.

He said if I was even more of a nut than I already am and if I was buying and not leasing, I could use premium for better peace of mind.

I pick up my car in 8 hours.

erisaman

I raise my cup (of tea) in a toast to wish you well!

I pay for mine in 8 hours and await delivery in 8 days (I hope).

Good luck - and best wishes to you, and all our forum contributors, for the forthcoming holiday break.

johnh7

I got mine. Everything I expected. So far - all parts seem to be working. The black/off black leather does look exactly as Stanwick's earlier pictures depicted. It's a very hot car.

Good luck with yours

jabotinsky

Just bought a 03 c70HT with 23k miles. Manual says it needs premium gas. Is this true? Any risks by not using premium?

tmart

Believe the manual recommends premium, but the car will run fine on plus or regular. If you want max performance, then use premium.

cricket4

We had a discussion thread going under "Meet the New Members" (off topic, obviously) but you can read it around messages #60-#70. Here is an article that I found on a Google search that you might find interesting. http://www.usatoday.com/money/autos/2003-07-30-premiumgas_x.htm

jeckles

From a technical standpoint, yes you can run on regular or premium. The computer can adjust the engine to compensate for the lower octane fuels.
Question is why bother? Maybe when prices were less than $1/gal and the difference was 20 cents, you were paying a 20% premium. With gas prices north of $2/gal the difference is <10% for premium. Hardly worth all the fuss .

qbrozen

By me, it is a 40 cent difference now, so at $1.99 for regular, the premium is about the same percentage. Not to mention, judging by percentages is not exactly logical for most people. 7% tax in my state doesn't phase me one bit when buying a $20 item, but it sure as heck makes a difference on a $20,000 car!

jeckles

gbrozen does have a very good point. 20% sounds high until you do the math and realize the annual difference is pretty small, especially if you factor in the lower fuel economy of the cheaper gas. I figure less than $20 per year difference based on 15,000 miles per year.

IMHO: Can't imagine putting low octane fuel in a turbo-charged engine, unless it is an emergency.

Sure it won't hurt the engine to run cheap gas occasionally, but you probably shouldn't buy a turbo-charged engine if buying premium gas is a problem (emotionally or financially).

When you put regular in almost any modern engine, it automatically adjusts to avoid damage. This sounds okay, but it means the engine runs richer (injects more fuel) and retards the spark timing to prevent premature combustion of the fuel (ping). This means less power, and poorer fuel economy. Plus the extra fuel is not always 100% consumed, and could be passed to the catalytic converter. This extra fuel is not good for the catalytic converter, and over time (repeated use of regular in a turbo engine) could cause premature failure of the catalysts.

Just my humble $0.02 on the issue.

rschleicher

I'm not sure I'm following all of the assumptions you made in your calcualtion, although I agree with your larger point that it is still not a huge amount of money.

Ignoring (to begin with) a possible mileage difference between premium and regular, 15,000 miles/year translates to 750 gallons/year (at 20 mpg), or 517 gallons/year (at 29 mpg) - using the city and highway EPA ratings. Even with only a $0.20 difference between regular and premium (in some areas it is more like $0.25, or even higher), this works out to $103 to $150 per year.

I realize that the above simple calculation assumes that the miles/gallon is the same, whether you are using premium or regular. So I guess the crux of the argument lies in whether there is actually a significant loss of miles/gallon in using regular, and if so, how much. I think this will largely depend on driving style, since the energy content of the two grades of gas is more or less identical. If you are a "heavy-footed" driver, then I think there will be more of a mpg impact, since the loss of peak power using regular (due to spark retardation, etc.) will lead to keeping the pedal down longer. But for someone who normally accelerates slowly, my guess is that the mpg penalty will be minimal or non-existent, and there will consequently be greater savings from using regular.

In my own case, I think the savings from using regular will be minimal, and my preference will be for obtaining maximum power capability from the engine.

I was interested to see that both the people at the dealer, and the owner's manual, "sanctioned" the use of lower octane fuels as being perfectly reasonable. Other cars I've had in the past that could use multiple fuel grades usually took more of attitude of "in an emergency I guess you could get away with using regular, but we really recommend premium".

qbrozen

oh, one more small thing I wanted to point out ... if you have a gas card that gives you rebates, as mine does (and if you don't have one, you are passing up on free money, in my opinion), then the difference between premium and regular is actually a bit less.

For example, my Hess card gives me 5% back at the pump. My bill is typically ~$350 per month. That is on regular gas. So the actual gas bought is about ~$368. If I was running premium, that would be about ~$441 retail ($73 difference compared to the retail price of regular gas) or ~$419 with my discount ($69 difference compared to my discounted price for regular). So the price difference for premium is reduced from 20% to about 16.5%.

jeckles

Okay owners, time to fess up!

What kind of mileage are you seeing with your cars, being a technical person here is what I suggest for posting:
1. Average Mpg Observed after full tank or more of driving
2. Auto or Manual Trans
3. Highway, City, or Mixed Driving
4. Type of Fuel Used (Gas, Diesel, Octane, and for gasoline if it is ethanol enhanced for smog purposes - sticker on pump usually says)

FWIW: most reformulated gasolines usually have less energy (btu) per gallon than pure gasoline, just like most lower octane gasolines have less energy per gallon than the high octane grades (see article referenced earlier). Of course the biggest influence on mpg is driving style and amount of stop and go driving...

Look forward to seeing some numbers and comparing results!

empty1

19 to 20 mpg using premium fuel on combo highway and local driving. About what I expected, its a pretty heavy car.

rogert1

A Few weeks back I had my volvo C70 serviced. Aprox 2 weeks later the engine light came on.It went back to the garage and was put on the diagnostic machine , it came up Bank 1,Fuel Rich,front Lambda sensor. It was re-set but the light came on again after about a week. The same reading came up,re set but came on. The sensor was changed, two weeks later it came on again and the same diagnostic reading came up. Has anyone had a problem like this? because its costing a lot of money !. Any ideas much appreciated. Roger

tom007

What year C70 is it and won't the warranty cover the repairs and give you a loaner car? How many miles are on car?

Hope you get it solved quickly, but seems as if it is a mystery to dealer by your report.Keep us informed as to solution when they find one. Thanks!!

Maybe Volvomax can solve it for you also.

qbrozen

well, i don't know what that is saying exactly, but the first thing I do when the word "rich" comes up in relation to fuel is pull the spark plug and take a look. Has anyone done that during your trips to the dealer?

rogert1

Thanks for the replies.
My c70 is a 2000 model.And the spark plugs have been checked and are fine. They were new at the recent service.
Since the engine light was put out (re set) the car doesn,t start so well ,which may be a clue to someone. Ive also had it suggested that a temperature sender may be at fault.
The light hasn,t come back on yet (2 days)

qbrozen

how long after the recent service did the light come on?

where did you have it serviced?

the reason I ask is because my volvo (and i hear most are) was VERY sensitive to the type of plugs. Anything other than OEM gave me problems, no matter how high-quality they supposedly were.

rogert1

As I think I said earlier it was between 1 and 2 weeks when the engine light came on first. The thing I don,t really understand is if it was a fault with the plugs,why doesn,t the light come on immediatly? and not at what seems to be a random time.One day I drove over 60 miles and the light stayed off. The garage which serviced my car was just a small concern where my brother in law works.They were not sure what the problem was caused by as the sensor seemed to be switching o.k.The garage I then took it to seemed sure,changing the sensor would cure the problem. My car has done 70,000 miles

qbrozen

sorry, i forgot you said that. it was a full day ago and i've read alot of things since then. ;b

well, all i've got for you is the plug issue i mentioned earlier. I never had the plugs throw a CEL for me, but they definitely caused a hard-starting issue for me (excessive cranking to get it to kick over). They also fouled out on me prematurely. And those were the expensive iridium tipped (i think that's what they're called). Once I went back to OEM, everything was well with the car again.

rogert1

8/5/07
Latest on the engine light;
C70 went in for its MOT today.They tested it with the engine light on for the emmissions and it passed no problem at all.The diagnostic code was PO172.and it said "System too rich" Bank 1 (2). I,ll phone the main dealer tomorrow with that code to see what they say.I drove for 80 miles over the weekend and the engine light had been reset (off).We had to stop to open a gate, and on it came! Ive got some volvo original plugs now which after ive spoken to the guy at volvo re the code ,ill fit if he thinks it will do the trick. Watch this space

rogert1

Just to let you know , my Engine light on has been cured following the fitting of a new MAF sensor, at the cost of £200 and 50p!+ labour and V.A.T.

jimtaylor1

I have a 2006 C70 that gets 25 to 26 mpg using regular fuel on combo highway and local driving.

jeckles

Hi!

We finally got our C70 delivered just before July 4th via OSD.

We are still collecting mileage data (and still going through break-in). The first few tanks were a bit depressing, until break-in when we started seeing 27-28 combined driving and 29+ on highway using premium (93). Some of the fuels are oxygenated (10% ethanol), which likely accounts for the variability in milage (along with traffic).

I accidentally put regular (87) in the tank a few weeks ago and dropped the gas mileage down to 24-25 combined (city/hwy). So for us in the midwest, where premium is only $0.20/gal more, it is slightly cheaper to use premium gas because we get better fuel economy {driving 350 mi costs $37.90 for 87 octane and $37.62 for 93 octane with regular costing $2.65 and premium $0.20 more}.

Pretty cool huh :P

oak7

@cricket4 said:
Did a Google search and found a good article at USA Today online. There is a lot of debate about Premium vs. Mid-Grade vs. Regular. I like the quote from the 45-year veteran engineer with Chevron Oil who also sits on the SAE committee regarding his wife's use of low octane. This article has helped me make up my mind. Here it is http://www.usatoday.com/money/autos/2003-07-30-premiumgas_x.htm

oak7

Excellent comments on premium vs. regular fuel. I have always wondered about it.

oak7

Is there any way to increase the fuel mileage? Has anyone experiemented with one of the "performance chips?"

oak7

Mine gets anywhere from 28-30 mpg on the highway and 25 while driving in and around rural towns. I am interested in the chip, too, though.