Declining gas mileage 04 V70R Topic is solved

Redbox · Post by **Redbox** » 05 Jan 2018, 18:13

Hi All,
I have an 04 V70R that I purchased last May. Very well maintained 240k miles. Only issue I've has since purchase was a bad rear brake line. No issues, no messages, runs great. Over the last few months, my gas mileage has been gradually going down. For the first several months I was averaging around 27.+ mpg. It is now down to nearly 20. Very little in-town driving. Not much time in the boost, AC off the majority of the time. Tire pressure good. No idle issues. I would expect something noticeable if it was a vacuum leak, or MAF sensor.

I had a similar issue with a Lexus, and it turned out to be a stuck brake caliper. Not seeing those kind of signs with the Volvo.

Anyone have a clue where I might start to figure this out. I have Vida/ Dice, but have never managed to get it installed on my laptop and working. No readings from a standard scanner.

Thanks for any advice.

Post by **abscate** » 05 Jan 2018, 20:15

Mileage will droop,when the O2? Sensors get tired. 100k is a good time to replace them along with plugs too.

Redbox · Post by **Redbox** » 05 Jan 2018, 20:36

There are two O2 sensors aren't there? Plugs would probably be a good idea. No idea when the last tuneup was.

Redbox · Post by **Redbox** » 05 Jan 2018, 20:54

Anyone have a part number for OEM spark plugs?

Post by **chrism** » 05 Jan 2018, 21:51

With 240,000 on the clock you'll want to make sure the PCV system is operating properly and service the system if it's clogged.

As for the OE spark plugs, I don't think what Volvo sells now is what the car was originally equipped with (Champion RC8PYP8).

Post by **matthew1** » 05 Jan 2018, 22:03

Redbox, take a look at this viewtopic.php?f=9&t=30306 That has spark plugs in it, linked.

This sounds like a lot like an oxygen sensor. Yes, there are two. If it is an O2 sensor, it's the front sensor.

Post by **jonesg** » 06 Jan 2018, 01:55

Redbox wrote: 05 Jan 2018, 18:13 Hi All,
I have an 04 V70R that I purchased last May. Very well maintained 240k miles. Only issue I've has since purchase was a bad rear brake line. No issues, no messages, runs great. Over the last few months, my gas mileage has been gradually going down. For the first several months I was averaging around 27.+ mpg. It is now down to nearly 20. Very little in-town driving. Not much time in the boost, AC off the majority of the time. Tire pressure good. No idle issues. I would expect something noticeable if it was a vacuum leak, or MAF sensor.

I had a similar issue with a Lexus, and it turned out to be a stuck brake caliper. Not seeing those kind of signs with the Volvo.

Anyone have a clue where I might start to figure this out. I have Vida/ Dice, but have never managed to get it installed on my laptop and working. No readings from a standard scanner.

Thanks for any advice.

Try to get vida working,
mine runs in win7 PRO.
you can install it in a virtual machine too.
I don't know enough to be of help, that's why I made sure to buy mine ready to run pre-installed on a laptop.
It's well worth getting it going.

Redbox · Post by **Redbox** » 07 Jan 2018, 17:15

Thanks so much everyone for the advice. I'll give VIDA another try (if it ever warms up outside). I think the PCV system is ok, at least no signs of trouble. I changed that all out on my old 850.

Redbox · Post by **Redbox** » 10 Mar 2018, 15:50

Does anyone happen to have a Bosch part number for the upstream O2 sensor. I ordered one that is said to be correct, but it has a much shorter wire harness. 2004 V70R.

Post by **abscate** » 10 Mar 2018, 18:31

Order these from one of the vendors here, eeuro, IPD, or FCP

eBay sellers rebox crap, counterfeit Bosch stuff, and other ways to waste your time