Really really bad fuel consumption

[ashyk36]

Hi.
I own a UK 1997 Mr2 Rev 4 N/A. Mileage is approximately 60K. There are no mods done to the car

Now the issue I have is that I feel my car is consuming too much fuel. The reason I say this is because I recently filled up a full tank which I believe is 55 litres. Now After 220 miles later I was as close to empty as possible when I had to fill up again. I have worked this out and to my horror and I am getting approx 18-19 MPG.

Now my driving style is 'normal'. When I say this I mean I have not took part in any 'spirited' driving what so ever because of the road conditions lately etc.

I commute 20 miles a day and (10 Miles work and 10 miles back) so I wouldn't say that this is too much of a short journey. My journey to/ from work is a little stop start but I wouldn't say it was very stop/start that it would give me such a ridiculous mpg. To put it into context, my journey to/from work takes approx 30 mins.

Now I have a slight suspicion that the issue maybe because of an air leak. I say this because my car 'whistles', the only problem is I have never owned an mr2 before and I don't know if this is the characteristic of the car.

The car on a cold start in the morning will rev as high and 2000 RPM and will eventually come down to sit at 900-950 rpm when warm. I Sometimes notice the rev counter moves up and down a 100 revs here and there but again I have never owned an MR2 so whether this is normal or not I am not sure.

I would really appreciate it if someone could please help me solve this issue. Below are 3 links to videos I have taken so that you car hear the 'whistling' I am talking about.
The first video is when I started the car from a cold start:

//sdrv.ms/19eieio

The second video is taken when the car was in motion (The video is black because I did not want to hold my phone while driving, but you can still hear the whistle).

//sdrv.ms/19eimi3

The third link is when I parked in my driveway at home, I have opened the door and recorded the engine sound. Bear in mind that because the house is right besides my engine bay so the 'whistle' is exaggerated slightly.

//sdrv.ms/19eioX5

If anyone could help me with my issue I would greatly appreciate your time. Thank you so much. I am on my way through my second full tank of petrol. As you can see I have just under a quarter tank remaining and so far have drove about 190 miles from full.

[danjama]

I'm also getting poor mpg though not as bad, getting about 300 from full to light on. So look forward to any replies. I think ill change the lambda sensor and see how that goes.

220 from a tank, i would weep.

[Ethan21]

Prob Lambda sensor

Do you have a weapon of an airfilter? That will cause issues

[GHOST]

Hell, that's bad. I'm getting around 90 miles on a twenty pound note which takes the needle to just over a quarter tank on my N/A and I thought that was terrible.

Is it just that petrol has gone up so much in price? 5 years ago I was getting 150 miles on a twenty in my old Rev3.

[rev3gtturbo]

Dont rely on the low fuel light as one day it might not come on at all.

I have 2 of these cars (rev3 turbos) and they both give me 30mpg as I do a lot of dual carriageway miles and usually dont get stuck in traffic jams.
On one car the needle goes well below the empty line and the other car will have run out of fuel by then.

[rev3gtturbo]

Ghost

It is very inaccurate to work out fuel economy based on how far a car goes on 20 quid of fuel or without filling the tank.

A much more accurate way is to fill the car up (and zero the trip meter), and fill the car up again when the gauge gets low (one or two small lines above empty, or earlier if the reserve light comes on!). The trip meter then gives the actual distance covered for the ltrs put in so the economy calculation is more accurate....

[tezmc]

No help here unfortunately, but my car is showing the exact same issues (Rev 5 N/A, 220-230 miles to a full tank & whistles like yours). I'll be watching this with interest, I thought it was normal fuel consumption! Is the MR2 not a 40l tank though?

[ashyk36]

No help here unfortunately, but my car is showing the exact same issues (Rev 5 N/A, 220-230 miles to a full tank & whistles like yours). I'll be watching this with interest, I thought it was normal fuel consumption! Is the MR2 not a 40l tank though?

I have googled it and I get a 55 litre tank. Any one know any different?

[ashyk36]

I have uploaded videos to youtube with the 'whistle' I am hearing:

The first video is when I started the car from a cold start:

www.youtube.com/watch?v=WRmO6E8 ... ata_player


The second video is taken when the car was in motion (The video is black because I did not want to hold my phone while driving, but you can still hear the whistle).

www.youtube.com/watch?v=JhECd0M ... ata_player


The third link is when I parked in my driveway at home, I have opened the door and recorded the engine sound. Bear in mind that because the house is right besides my engine bay so the 'whistle' is exaggerated slightly.

www.youtube.com/watch?v=Y1Gcwf4 ... ata_player

[tezmc]

Your YouTube links don't work, it looks as though some of the URL has been cut off when you've pasted them in.

[Donato]

I averaged about 35MPG motorway driving over summer.
Regarding the issue about high cold idle, this is normal so long as it comes down once the engine is warmed up. But because it is idling slightly lumpy, i'd suggest possibly a lambda sensor would be at fault. Which would explain your fuel consumption.
Are you able to smell overfuelling at all?

My car also has a slight whistle under acceleration, but i've not noticed any loss in fuel consumption. It's probably a leak from around the airbox or piping to the throttle body. That shouldn't cause high fuel consumption though.

[tezmc]

Mine's definitely running rich, you can smell it from the exhaust. What's the OEM lambda on these, are they Bosch ones?

[Donato]

Mine's definitely running rich, you can smell it from the exhaust. What's the OEM lambda on these, are they Bosch ones?

Off the top of my head, i think they are Denso. That's generally what Toyota tend to use. There should be one in your B-Pipe (Manifold to Cat).

[tezmc]

Off the top of my head, i think they are Denso. That's generally what Toyota tend to use. There should be one in your B-Pipe (Manifold to Cat).

Cheers. Is it accessible from the top of the engine on an NA like the Turbo? Just seen this guide:

http://forums.mr2oc.co.uk/know-your-2-k ... bartid=157

[DB Mr2]

Sticky/siezed calipers?
Could this also help to lower your mpg?

[danjama]

Sticky/siezed calipers?
Could this also help to lower your mpg?

Yes of course but how drastically would depend on the severity of the seizure. Also check tyre pressures and for any signs of wheels/tyres rubbing on bodywork/suspension etc.

Mine has an induction whistle which is only really noticeable on cold idle. It goes away when warmed up.

Cold idle speed varies with outdoor temperature - 2000rpm now it's cold outside. Was 1500rpm in summer. Warm idle is 750-800rpm.

[GHOST]

Ghost

It is very inaccurate to work out fuel economy based on how far a car goes on 20 quid of fuel or without filling the tank.

A much more accurate way is to fill the car up (and zero the trip meter), and fill the car up again when the gauge gets low (one or two small lines above empty, or earlier if the reserve light comes on!). The trip meter then gives the actual distance covered for the ltrs put in so the economy calculation is more accurate....

I totally agree mate, but I'm still under the impression that by putting a full tank of fuel in I'm carrying loads more extra weight and getting even worse mpg lol.

[Peter Gidden]

I'm still under the impression that by putting a full tank of fuel in I'm carrying loads more extra weight.

50 litres of fuel represents about 3% of your car's weight. So maybe time to change your impression...

[Kongaroo]

If your mpg is that bad I would check that your thermostat isn't stuck open as well. Does the coolant temperature gauge behave normally?

[ashyk36]

Prob Lambda sensor

Do you have a weapon of an airfilter? That will cause issues

No I dont. The car is fully stock. No airfilters etc