Ls 400 Mpg

bigvinny · October 10, 2008

What is the average MPG of a 94 model year LS 400? I have been driving mine for about three weeks now and every week it seems I am putting more fuel in and my fuel low warning light seems to be coming on earlier each time !! I have worked out that this last week I was returning 12mpg (based on 60 miles covered with 5.14 gallons).

I am doing short journeys (2 miles approx., 4 or 5 times a day). I know the MPG would be better over a longer distance but 12mpg well below what I expected (and I tickle the throttle, you can almost hear the car laughing!). I would hate to think what it would do if I had a lead right foot.

Anyway, it would be interesting to know what other LS 400 owners are getting to the gallon so I would appreciate your posts. :D

Chris Skelton · October 10, 2008

What is the average MPG of a 94 model year LS 400? I have been driving mine for about three weeks now and every week it seems I am putting more fuel in and my fuel low warning light seems to be coming on earlier each time !! I have worked out that this last week I was returning 12mpg (based on 60 miles covered with 5.14 gallons).
I am doing short journeys (2 miles approx., 4 or 5 times a day). I know the MPG would be better over a longer distance but 12mpg well below what I expected (and I tickle the throttle, you can almost hear the car laughing!). I would hate to think what it would do if I had a lead right foot.

Anyway, it would be interesting to know what other LS 400 owners are getting to the gallon so I would appreciate your posts. :D

Much too low. 20+ should be, even in town. Who that with that siphon pipe? (Check pipes etc?)

ffcary1 · October 11, 2008

Is your fuel gauge working correctly? that would be the first concern as the fuel gauges are very prone to going wrong, i would look to replace the caps on the instument cluster first and then see if the fuel return to distance travelled goes up. or down. i have jut sorted mine and the needle is falling at a very slow rate.

fill the tank till the pump stops then take it on a good long run and make a note of the dstance driven, than refill till the pump stops then work the miles per gallon.

JellyBean · October 11, 2008

Short journeys are disastrous for fuel consumption - when engine is not at working temperature. I once got a call to investigate a chap's wife's Austin 1100 which was doing about 18mpg. I checked all the usual stuff and could find nothing wrong. Turns out she only used the car for the school run which was less than one mile each way !

steve-bedford · October 12, 2008

My Series IV ranges from 18MPG to 24MPG.

In the 10 months that I've owned it it's averaged 20.5MPG (this is the real figure - not the one reading on the computer) and is based on my daily 18 miles (9 each way) commute which is all villages, corners and fast country roads.

If I was regularly cruising at 60ish on motorways and A roads I would expect it to be nearer 25MPG or maybe even more.

bigvinny · October 12, 2008

Thanks to all for your advice. With regards to the fuel gauge, mine seems to be working OK in that I put fuel in & it seems to register a proportional amount. It is slow sometimes in rising to the registered amount but I can put up with that. {This is a replacement speedo (the first one I had repaired burnt out as soon I put it back in & I don't want to risk that again!)}.

Austin 1100!!! How long ago are we going back?