Excessive Fuel Consumption On 1.8 Vvti Engine

[jimbobsteele]

My Celica 140 (bog standard model, no frills) is great!!

But over the past 6 months, I've noticed the fuel consumption getting progressively worse. Typically, a tank of unleaded will last 250 to 300 miles. An that's with some generous coasting down hills. (Not exactly what the car is designed for!)

My local dealer, who are normally very good, did examine the car. They put it on some sort of monitor and drove it around for a while. Apparently, the monitor showed no faults or anomalies. But I suspect they never got it about 4000 rpm!!

I do keep track of MPG (I'm a bit anal about it) and have found this averages out at 31.5 MPG. And bear in mind, this is with very gentle driving. I can never get anything higher than 33 MPG, even on a long motorway run. If I drive it with a bit more enthusiasm, this quickly drops to the low to mid 20s.

Does anyone think this is lower than they would expect?

I've tried experimenting with different petrols... originally, I thought Tescos/Sainsburys was lower quality. But this doesn't seem to have much of an effect. And a recent change of tyres has made no difference.

Is it feasible that the car is running on its 'cold start' program? So, in my laymans terms, its automatic choke is stuck out?

Thanks - Jamie

[TheNissanMan]

They sound like very good figures to me....

[Oli]

i get 28mpg out of a 1.5 TSport. That's with a bit of both. Hard and Soft driving.

So for a 1.8 that sounds ok to me.

[zee007]

2.0 VVTI in mine.... currently get around 20-25mpg......... after supercharger is fitted, i expect around 15mpg....... :(

[Monster-Mat]

15mpg...........i wish

after the conversion i recon i will be getting 1mpg

i can :D now, but some how i think long run i will be :o :(

but theres loads of petrol left in the world

[zee007]

15mpg...........i wish

after the conversion i recon i will be getting 1mpg

i can :D now, but some how i think long run i will be :o :(

but theres loads of petrol left in the world

[TRDperformance]

Those are not bad numbers. They may not be perfect but i've seen worse and i've seen better, on stock models. You could try an injector cleaner or a higher octane gas for a little while, couldn't hurt and it'll help keep things clean. If you'rereally concerned about the amount of fuel you're consuming, you can get a chip tuned with multiple settings. One of those settings, the "grocery-getter" setting, you could adjust for optimum fuel efficiency. This could cost some $$ though.

Personally i'd say you're just fine. Small changes can occur when the engine actually gets broken in.

[spwolf]

31.5 mpg for a celica aint bad at all... its a sports car, and i bet you like to wind it up, dont you?

i have been getting 19 mpg in my corolla ts lately

:P

[Nichanor]

Am just suprised that some one is complaining about a 33mpg on a 1.8vvti engine. I wish i had that!!!! Am getting almost half of that on high way. I have just tuned my engine(from oil change, spark plugs, air cleaned) no change at all. Am getting 5km/lt in urban drives and 9km/lt on high way... I can do anything to get 14km/it(33mpg)... Any one that can help. Please advise. 

[FROSTYBALLS]

14mpg urban, 25.4mpg highway.

[FROSTYBALLS]

9 minutes ago, Nichanor said:

Am getting 5km/lt in urban drives and 9km/lt on high way

14mpg urban, 25.4mpg highway.

[Nichanor]

What can i do...

[gezhenry]

Yeah I do actually agree with the OP up until a couple of years ago I was getting the manufacturer s of 37 mpg or higher on longer runs of over 400 miles per tank on a high mileage and not particularly well serviced 06 1.8 vvti.

However upon fitting an sri intake it got decimated to your levels and Id also like it back!!

I don't know whether I could setup my intake better, but I assume when I take it back to stock it will re-improve.

Unfortunately I don't have any good answers for u that id also like too.

i believe a dirty maf causes common inefficienc ies and is easily tackled so that may help along with thinner spec oil and premium fuel as mentioned which has other benefits for our engines too.

Mines now pretty highly maintained but still remains low id be interested if you manage to improve yours ba ck again.

[Konrad C]

On 7/21/2019 at 9:17 PM, gezhenry said:

Yeah I do actually agree with the OP up until a couple of years ago I was getting the manufacturer s of 37 mpg or higher on longer runs of over 400 miles per tank on a high mileage and not particularly well serviced 06 1.8 vvti.

However upon fitting an sri intake it got decimated to your levels and Id also like it back!!

I don't know whether I could setup my intake better, but I assume when I take it back to stock it will re-improve.

Unfortunately I don't have any good answers for u that id also like too.

i believe a dirty maf causes common inefficienc ies and is easily tackled so that may help along with thinner spec oil and premium fuel as mentioned which has other benefits for our engines too.

Mines now pretty highly maintained but still remains low id be interested if you manage to improve yours ba ck again.

It shows how good Toyota balanced fuel efficiency, with emissions and driveability. 

The induction kit has changed the parameters, so the ECU is trying to match the air/fuel ratio. If the air is being warmed by the engine heat, it will be less dense. A tune up if possible, could help.
A simple test would be to pull the EFI fuse, so the ECU can relearn the induction kit. Then see how far you go, and what is your fuel economy after a few tank fulls.

Edited July 30, 2019 by Konrad C
spelling correction