Optra's Fuel Gauage Problem

[Kopikao]

Mine the aircon fan's fuse burnt before.. car stationary and aircon blows hot air. The fuse actually blown twice, but dunno what they did the second time and rectify the problem..Till now no recurrent of the problem

[Stary]

Bro...yours is manual, mine is auto...hard to compare apple to apple la....

 

mine definitely 2200-2300rpm at 100km/h.....very sure....

[Cracker]

my aircon is still working, just tat bundled with the cool air is "burnt smell" fumes.

[Cracker]

Went for my first svc today....

 

also did a topup...trip meter was just 574 km but top up almost 50 litres..giving a figure of 11.5.

 

So this is my data

1) 1st tank......travelled 583 km ..topup 45.7 litres meaning 12.75km/l

2) 2nd tank......travelled 575 km...topup 50.0 litres meaning 11.5 km/l.

 

SA had replaced my air blower....also reset my ECU.

But I am still getting 3000 rpm @ 100km/h.....can other bros driving the manual version pls indicate ur rpm at 100 kmh or 80 kmh..for the latter my rpm is 2000 rpm.

 

actually such figure is similar to conti car...just want to know is it true for chevy too.

[Takanori]

Btw juz to let u noe I nve hit til 3k rpm b4 even when i travel at 110km/h. I drive auto transmission but I tink not much different in terms of rpm lah.

[Cracker]

hmmm....can other manual owners pls comment ?

[Cracker]

I am also having the same, 100km/hr at around 3K rpm (less), 80km/hr at 2k rpm...

 

are u driving the manual version ?

[El69]

All makes and models will have different rpm readings between the Manual and Auto models. The difference in rpm reading is a result of the gear ratio being different between a Manual and Auto (even if same model, engine cc, power and torque rating). The purpose of having different gear ratios is due to the difference in the way the gearbox operates (clutch system vs torque converter).

 

As such, it is not possible to compare variables such as 0-100km/h, top speed, FC and rpm reading at a fixed speed. Such variables are seldom the same between a Manual and Auto.

 

The Optra(M) comes with a 5speed gearbox whereas the 1.6(A) comes in a 4speed gearbox. The gear ratios are different throughout to ensure that full power and driveability is not compromised too widely between an auto and manual.

 

A manual car travelling at a higher rpm (say 3000rpm @ 5th gear)may not consume more fuel that an auto running at lower rpm (2300rpm @ 4th gear) at the same speed. This is because there is less power and transmission loss through a manual gearbox (using a clutch) as compared to an autobox (using torque converter). Its not the number of gears (5sp vs 4sp) but rather the gear ratio and final drive as calculated by the gearbox maker that makes the diff in rpm reading at the same speed.

 

Its like you ride a bicycle with gears and use them to change according to load and speed so as to reduce the effort needed to propel the bicycle. Those who cycle should understand this theory of gear ratio, final drive, load, speed and no. of gears.

Edited January 28, 2005 by El69

[Cracker]

I agreed with u having studying about it decade ago

I just need fellow owner of the manual to confirm if their readings are same as mine.

[Sky8807]

I am also having the same, 100km/hr at around 3K rpm (less), 80km/hr at 2k rpm...

 

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Something not right.

If 100 @ 3000 rpm , 80 @ 2000 rpm - not tally leh

If 1000 rpm get 40, 2000 get 80, then 3000 shd be 120.

If 3000 rpm get 100, then 2000 rpm shd be 66.6 and 1000 33.3

 

Maybe the rpm gauge not accurate

[Cracker]

Is ur ride auto or manual ?

 

anyway the rpm to speed is not proportional, its depends on how what is the gear ratio..

[Sky8807]

I'm driving a manual car.

When comparing the rpm and speed reading, we have already set a contant that is the gear is set at 5th and reading are all taken from it.

 

If 1000 rpm at 5th gear give you 30 km/h(example) then 3000 with give you 90, 4k @ 120, 5k at 150 and so on. Reasons is the gear ratio(manual) is already fixed, no horse run in this case.

 

If for any reasons the sum does not add up, then 2 possibilities, clutch slippage or the rpm reading erroneous. my views.

Edited January 29, 2005 by Sky8807

[Cracker]

hmmm...i will do a similar test later and file in my "report".