Disappointing Mpg On Mk1 Avensis 1.8 Gs Estate (1998, Lean Burn)

[Konrad C]

This morning it was 1-2oC, and using air-con, rear window defrost, I only saw 1600 rpm. Within a few minutes after a couple of miles the engine had partly warmed up, and showing 700 rpm.

I have seen close to 2000 rpm if I let the car just fast idle for a few minutes. The engine then slows during the warm up.

I just started my engine and it went up to 1600 rpm. In the car writing this post.

Don't worry about the high idling speed. It goes down fast and when the engine is warm stays around the 700 rpm mark.

[Radiodanno]

Hi op. Just to add a few thoughts.

You have to bear in mind that the 7afe engine is late 1980s technology. It's not going to compete with the zz engines of the newer cars for mpg. However, they are hugely preferable for reliability. I've moved back from a 1.8vvti which gave me a solid 47mpg to a 2.0 3sfe that gives me 40mpg. More expensive on fuel but, per mile, probably as cheap when you factor in no oil to buy, cheaper tyres and the ease of working on them. Take some comfort in the fact that your car will still be running when only the rats inhabit planet earth.

You can chase and chase and chase these things, but it will still pool your enjoyment of the car. You may find that with nice eco tyres and nice summer temperatures that you easily clear 40mpg.

One thing I will say, you won't know exactly what economy you're getting by just putting £20 and waiting for the light. You need to fill it to the top, drive it and then fill it to the top again. It's the only accurate way, everything else is just a guess.

Just enjoy it.

[Harry Carri]

Hi,

From a cold start on Friday morning mine idled at 1700rpm, this morning later in the day so probably warmer 1600rpm.

On the economy debate, I agree with a lot there Daniel, I had a look on the website fuelly and I am doing better than most on there. Yes brim to brim is going to be more accurate. I think I struck lucky with a frugal Carina e and that is what has given me such a bea in my bonnet.

I do think it is a great car and refer to it as my Derbyshire Lexus. Comfortable, smooth riding, well equipped, supremely reliable and bought for less than a grand.

[fractureman]

My fuel economy much better after new gasket where down pipe joins base of exhaust header.

Camberley etc don't have that part, I knew it was a big b*gger cos what was left of old one looked like wire whool lol

£18 later for part from Mr Toyota & fuel economy is back to where it was, after disconnect Battery to wipe fuel ECU.

That's on a 7FE 99 avensis

[Konrad C]

Hi op. Just to add a few thoughts.

You have to bear in mind that the 7afe engine is late 1980s technology. It's not going to compete with the zz engines of the newer cars for mpg. However, they are hugely preferable for reliability. I've moved back from a 1.8vvti which gave me a solid 47mpg to a 2.0 3sfe that gives me 40mpg. More expensive on fuel but, per mile, probably as cheap when you factor in no oil to buy, cheaper tyres and the ease of working on them. Take some comfort in the fact that your car will still be running when only the rats inhabit planet earth.

You can chase and chase and chase these things, but it will still pool your enjoyment of the car. You may find that with nice eco tyres and nice summer temperatures that you easily clear 40mpg.

One thing I will say, you won't know exactly what economy you're getting by just putting £20 and waiting for the light. You need to fill it to the top, drive it and then fill it to the top again. It's the only accurate way, everything else is just a guess.

Just enjoy it.

Daniel,

A great post and the thought behind it.

Konrad

[golders]

I agree, fill your car to the top, do your normal tank full of driving, then fill it to the top again.

Make a note of how many litres: 45litres etc, then put the litres and the miles you covered into this handy MPG Calculator:

http://www.mpg-calculator.co.uk/

[Harry Carri]

Hi,

Konrad, good call on the suggestion of checking the linkage on the vacuum switch controling the inlet butterflies. I hadn't managed to find it the first time but I did yesterday afternoon having re read posts and searched back on the subject of the vacuum switch and inlet manifold. I think it was one of yours that described where the switch was helped me more than the photos.

Yes the lug / peg had worked it's way out of the hole so the linkage was in two peices. Quickly and carefully popped back on. Had a lovely drive to and from work today, revs gathering quicker, more responsive and a bit of the lean burn growl that I remember from the Carina e. That should be job done, feels brisker and should be lean burning. Hurrah.

Thanks again Korad. Good advice.

[t-spiritpete]

You won't go far wrong with advice/help from Konrad :-)).

Pete.

[Konrad C]

Glad to have helped Matthew.

A happy ending.

Konrad

[Nigemeister]

I drive a 1.8 avensis SE 1999 with 172k on clock, which I have had for 6 months and am doing 750 miles a week in. I generally return 48mpg in colder weather and 52mpg in warmer climes. Only way I get this is by a light right foot. I regularly use premium unleaded and prefer BP ultimate to get a clean engine. If I exceed the 3k mark on the Rev counter I see a commensurate reduction in fuel level. My car exhibits a slight hesitation at about 2.5k rpm under load on a hill so am hoping the next full plus service with spark plugs and fuel filter will help this. My advice is keep below the 3k rpm, regular manufacturer interval servicing and good fuel. Btw, love the avensis mk1, hope I can keep it going for a few more miles yet.

[Harry Carri]

HI,

Nice post Nigel, those are fine looking figures you have returned, diesel-why bother ?

I had forgotten about this thread. Back in July my car failed it's MOT. It needed a new section of exhaust, so it had a new down pipe and centre section containing the cat.

I did mention this in relation to a post of Konrad's who had similar exhaust problems however I did not update this thread as the new exhaust parts found me the remainder of that 10% increase in mpg I was seeking to match my old Carina.

As soon as those new exhaust parts went on the fuel consumption improved. All summer long I have been averaging 42-45mpg and now it is colder 38mpg. I have exceeded 45mpg the odd time when doing more A road driving. Happy with that.

[Nigemeister]

That's really interesting as mine is likely to need a new exhaust soon since the sections separated due to freak rain shower and me hitting a deep puddle. Kwik-fit guy worked some magic with a hammer and new bolts and got it back together again. Would you mind if I ask where you got your exhaust as I have prices quoted of £400 upwards? Also have you tried cataclean from euro car parts, it makes some bold claims for improving mpg by cleaning out the cat?

[Konrad C]

Matthew/Nigel, I am glad you are enjoying your cars. The fuel economy you are both getting are good compared to most cars, including those with smaller engines.

You may have seen my latest post regarding me having to replace the new rear pipe after 4 months. The replacement is far better, and has not bedded in yet. The new front and catalytic converter are fine, so I am much happier with the exhaust now. Basically the resonator just after the cat' had failed.

My car is a lot smoother now.

[Harry Carri]

Hi,

That's really unlucky Konrad, 4 months in and having to refit.

Nigel, my local garage sourced the exhaust sections and fitted them. The cat section was approx £80 from memory. I did post some details on Konrad's thread about his exhaust failure. The part numbers my garage quoted me matched up with a Bosal part.

As for Cat a clean I did put some through earlier on in my quest for mpg. Can't say if it improved things but I am sure it did no harm.

If you can't find that thread about exhausts post again and I will dig out my paperwork from the garage.

[Konrad C]

Matthew,

I found the original part numbers you mentioned and re posted. Actually I was adding to the post when you posted to this.

http://www.toyotaownersclub.com/forums/topic/162085-how-do-replacement-exhaust-catalytic-converters-perform/

It seems that I had a faulty replacement rear exhaust as I have driven the car and the car is a lot smoother. As I said before, the replacement is slightly louder the than original old exhaust, but far more quiet than the 'August' pipe.

Hopefully I won't need to go under the car again, time will tell.