850 GLT 2.5L 20V - Fuel Consumption

Citrofan · Post by **Citrofan** » 17 Feb 2007, 11:33

Hello again.
I have been ride my new Volvo 850 GLT 2.5L 20V for few weeks. I drive only in city in Poland when I live. Now I think that the fuel consumption is too much. Now is winter and there is 0-6 celsius (32-42 Fahrenheit) degrees outside and there isn't snow. I can ride 15 miles per gallon (100km/16l) and i hear that this engine could have less fuel consumption in city traffic that i have. I read that they can drive 19 miles per gallon.
The fuel end ingnition system have no error in ECU, i've just been checked.
Is there something I can do?, that my car will have lower fuel consumption? I was driven very gently (never get higher than 3000rpm) to test ten minimal fuel consumption in city and is only 15 miles per gallon

Thanks, and ones again sorry for my English

Post by **MadeInJapan** » 17 Feb 2007, 13:20

What year? GLT's were different from year to year. non-turbo at first and then turbo. Btw, the mileage in the city is about right.

Citrofan · Post by **Citrofan** » 17 Feb 2007, 14:44

Year 1994, 170HP non-turbo.
I think that 15 miles per gallon is poor, i know i drive only in city but other user who have this cars in Poland can ride 19-20 miles per gallon.
It is posibble that i have something wrong? maybe the MAF sensor or what?

Post by **MadeInJapan** » 17 Feb 2007, 14:50

No, I don't think so...it is about right...you have a very heavy car and gas mileage goes way down when it's really cold. This is unless you were getting considerably better before and then suddenly your mileage got bad...a lot of times, this is a sign of an 02 sensor going bad (even before codes show up). The same thing is happening to my mileage now with very cold temperatures. Of course these cars get very good mileage on the highway at a steady speed of 70-80mph even in the cold. Warming up to a good temperature seems to help them a lot.

Citrofan · Post by **Citrofan** » 17 Feb 2007, 15:42

I don't understend everything you wrote but... what is 02 sensor and should I replace them? How can I warming up to good temperature when i drive morning 3 miles to work, afterk work i drive about 5-10 miles and I'm back at home again

But all the time i drive really gently. My friend have an 1993 Chrysler Voyager with 3.3L engine and his milage is 16-17 miles per gallon. I still think that my car should have better result, not much more but 18-19 miles per gallon in city would be great.

Post by **MadeInJapan** » 17 Feb 2007, 17:59

I'm sorry...I didn't realize that you didn't know about the common parts on these cars that need replacement after awhile. The O2 sensors (your car has 2 of these and they're called oxygen sensors) that are before and after your catalytic converter (in your exhaust system) go bad after about 100K miles. Usually the one in front of the CAT converter goes bad first. When it completely goes, your dash will light up with a check engine light (CEL). In Europe, I believe this is called a lambda light. Anyway, if you have your code scanned at that point through the OBD-II port (On-Board Diagnostic) under the coin tray (under your ash tray) you will read a code that is for the 02 sensor. Before the sensor goes completely bad, gas mileage will decrease. This could be what's happening to you. However, 850's like to warm up and be driven hard...actually they need to at least once a week or so. Your 3-5 minute drives and your gentle driving is actually not helping very much. Okay, do this- pull your engine oil dip stick (the stick to measure your engine oil quantity). I'll bet that it looks thick or creamy on the bottom...like a milk shake. This is because the condensation in the engine is not burning off. You really need to get your car warmed up and drive it hard, even if this means that you take a detour to getting home once or twice a week. Your mileage should improve and your car will run better.

Post by **Ozark Lee** » 17 Feb 2007, 18:19

Year 1994, 170HP non-turbo.
I think that 15 miles per gallon is poor, i know i drive only in city but other user who have this cars in Poland can ride 19-20 miles per gallon.
It is posibble that i have something wrong? maybe the MAF sensor or what?

I had the same problem with mine. It turned out to be the airbox thermostat. I now get in the low 20s mpg in the city and 30+ mpg on the highway.

A good thread with pictures is here.

https://www.matthewsvolvosite.com/chat/p ... php?t=8830

Do widzenia,

Sorry if that is not correct - at least I tried.

...Lee

Post by **MadeInJapan** » 17 Feb 2007, 22:02

Ah...now I remember....yes, the airbox thermostat on a non-turbo.
Good catch there Lee!

Citrofan · Post by **Citrofan** » 18 Feb 2007, 04:00

Ozark Lee wrote: I had the same problem with mine. It turned out to be the airbox thermostat. I now get in the low 20s mpg in the city and 30+ mpg on the highway.

A good thread with pictures is here.

https://www.matthewsvolvosite.com/chat/p ... php?t=8830

Do widzenia,

Sorry if that is not correct - at least I tried.

...Lee

Many Thanks!
Tomorrow I try to check the airbox thermostat. Yes I have the lambda sond, but I think that only one in front of the CAT converter and to check it i think i will must go to specialistic service

I don't also have the OBD-II port under the coin tray, in Europe they were at 1995 i think.
I try to chceck everything and let You know about results.

Do widzenia, is coreect! I don't expect that someone here is try to speak in polsih

Post by **billofdurham** » 18 Feb 2007, 11:56

I don't also have the OBD-II port under the coin tray, in Europe they were at 1995 i think.

That is correct. Some '95 models were fitted with both OBD1 and OBD11. OBD11 only was on the very late '95 cars which were, in fact, '96 models. I have one and miss the box in the engine compartment.

Bill.