rattling sound is hard to avoid for car, even teana, mazda3, altis and civic does.
most of the user will try to figure out and visit SC a few times to solve the problem.
it depends on owner mindset, some try to locate and then try to solve it, some complaint and hope miracle to happen.

not sure how is your FC but on highway i can get as low as 6l/100km if i want, constant speeding at around 170km/h still give me around 7l-8l/100km.
city drive is around 9l-10l/100km, heavy and slow traffic and less than 10 minutes drive for daily trips.
you will find both figure very acceptable and in fact competitive, if you have ever do any research or comparison on C segment cars.

also, you can compare with your friend's Camry, but do compare with other Camry and Forte as well.
last, car is not about FC, for those who worried so much about FC, big car are not for you, get a Viva for maximum satisfaction.

You expecting prius fc for a 1.6l car that weighs close to 1.4t? Ok you say you compare your friend's camry to your car. How would you know how his driving style is?

You buy such a big car dont expect fuel consumption like a viva. Else get a hybrid.  I agree that forte is not the best fuel saving but its not the worse either. Control your driving style and you can see savings. Flooring it every once in awhile is fine 

if your FC still suck, its probably you who really suck till your car really wanted to suck you off.
i know, there are many bigger car have better FC but there are many have worse FC too.
they all have their pros and cons.

just blame yourself did not do enough research when you bought your car rather that blaming this and that here.
improve yourself first before you want other to improve, if not you will drag others to your standard.

Wah.. so simple? what did they do to the tyre? but i read a lot in forum. they said is the chamber problem.

Now my wife owning a Preve CFE..& Preve CFE's FC as of now is nowhere near my Forte FC especially on highway cruising (see comparison pics below).

Chilled out bro. Everyone love our Forte. Anyway I dont see any big difference between 10 or 11 / 100km. I used to look at the instant bar and maintain at between 10L but end up ma get extra 20-30km. Not so obvious. Now I dont care anytime wanna rush just step the pedal and what I've got was 10.5L/100 and 20km lesser only....
So far I can get around 450KM full tank with ODO <100

The best I get is around 410km and thats on a 1.6. But its getting better la I suppose, previously around 360-370 for full city driving. This improvement is using Caltex Ron95

For city driving, the Preve CFE's FC ranging from 8.5 to 9.5L/100km mostly from my observation. But that has been done in Alor Setar town instead with much lesser traffic jam & lesser stop & go period. In Alor Setar, my Forte 2.0 also getting the same FC easily. For KL city driving, my Forte gives 9.x to 10.x mostly..but i'm yet to have an opportunity to measure the Preve's FC for KL city driving yet..so i reserve my comment on this, though deep in my heart i believe that it wont go far less than my Forte.

Tonight I go take all my mods out.. Someone go burn my car.. I wanna change to 2.0 also.. Lol!

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Added on September 21, 2012, 11:57 am

Anybody tried LiquiMoly?

that burned one is 1.6...
he bought another one..this time 2.0...

bold fonts maybe will help for your fuel save.

Lol.. Go google and see.. Den you will know...

i use the Syntium 3000 FS engine oil provided by the SC from the first service till now (60k+ km in mileage). I did changed the stock air filter to Simota stainless steel air filter (at 20k km mileage) & also changed my rims to a lightweight 16" rims + Iridium spark plug (at 30k km mileage). However, the FC measurement that i've mentioned before (except for Alor Setar town driving) is being taken before these mod has been done (my car is still in stock condition that time).

just wanted to comment a bit, no offence.
btw, you just got your car i suppose not long since your mileage is so low and you mentioned you spend so much on petrol every month. A good info to share to you is, most new car will have very poor fc. It is still under the lubrication period. You can go ask around to anyone how's their fc when they just got their car and after at least 10k mileage. I am not sure about other car maker, but toyota with its vvti engine, now dual vvti, is very famous for very very good fuel consumption where you will be satisfied. try to bear with it. is common. I am not driving a forte, so maybe my comment doesnt valid, but i think this can be a reference. when i just got my persona, i went for a trip from JB to KL which one tank of petrol is not enough!! means i cant get even 300+ km on highway drive of 90-110km/h. but now i only use half tank of petrol to travel from JB to KL. dont worry, your fc will improve. i looked and i think your FC is not a major issue. but do tell when your FC still remain the same after 10k mileage. a vios can get around Rm0.13 per km with a less than 1000kg car with toyota vvti engine. what do you actually get?? if you can get Rm0.15 per km on a 1200+ kg car, dun complain lah. I actually same with you, getting very poor fc and i travel a lot. my fc is at Rm0.18 per km. so looking for option to mod. I don't suggest you to mod your car especially those engine parts at the beginning. a lot of mod will void warranty. but quite a lot ppl got improvement in fc after mod. See if you satsified with your FC after your car lubrication service is over. 

Facing the same problem..seems that the reception signal goes up and down...complain to SC d...and they have recorded it and send to hq..hopefully when i go to 1k service will do something.....

yes, toyota and honda very good in fc and still does not loose out on power. Like i say most of the reason of the car you mentioned having a bit high of fc is new. toyota and honda run for many years with high reliability mah. Kia and Hyundai is much better now if compared to last time. From what i know, Kia optima(old one) have very good review. haha, all these things take time to prove it lah. but then I am always complaining why I cant have an fc of a toyota vios. then one day someone show me this.

My persona = Rm56k full spec when i bought it
vios full spec =Rm80+k full spec

I save 24k edi.
Vios fc is around Rm0.13/km maybe we just count it as Rm0.10/km
My car Rm0.18/km we assume Rm0.20/km
So every km if i drive vios i save Rm0.10.
After 100k mileage i saved Rm10k. The petrol saving will be need me to reach 240k mileage to break even the previous money I payed for the car. So, I just stop complaining. with the Rm24k you can wonder what mod i can do to my car edi. XD but buying a proton is like gambling, touch wood, my car never give me problem   
but i am very addicted to the forte. so many things at such price.
If you really want to mod for petrol saving, the obvious combination is extractor + lightened crank pulley. This one no proof because you driving forte, but it works on proton.

oh....anyway what is ur millage now? wait >10k will be better.

Try to speed up ur speed to 180 km/h and hold a whole.....later you will feel ur fc improve.....  

i personally don't recommend 20weighted oil. although kia do so. 20 oil will give you very nice fc very good for city drive. but it offer very low protection to your engine. but if kia say yes then maybe no problem lor. just my opinion. I don't even dare try 30 weighted as I rev i scare no protection.
saga blm is also a nice car mah. cheap and practical. the handling and comfort pwned cars at its price range.
Yes, people are quite typical about proton, mainly bcoz of the frequent problem from the car although most of it are quite minor which i think you will know too as you are driving one. but if it is a major one, proton will look into it quite seriuosly. Someone in the Persona club got a new engine after he got his car less than a week. haha. after that the compensation i forgot edi. dugong, dun want mention, is bcoz of the demand is high the price went up. if last time I am ok to buy a vios, it is still worth it. Now? is buying a basic car with not much gadget. The forte and elantra if the sales continue to goes up in this rate, i think in few years the price will be like dugong also or even higher as it has more things to give. Yes, forte most value but i personally say it will be applicable to 1.6SX and 2.0 only.

Forte is C-segment car..means that, the same segment as Altis, Civic, Lancer, Elantra

K5 is D-segment car..same segment as Accord, Camry, Teana, Sonata

Where else, Vios is B-segment car..comparable to City, Fiesta

i personally don't recommend 20weighted oil. although kia do so. 20 oil will give you very nice fc very good for city drive. but it offer very low protection to your engine. but if kia say yes then maybe no problem lor. just my opinion. I don't even dare try 30 weighted as I rev i scare no protection.

Yeap, consistent +-300kms for RM80 although now already clocked 22,000kms.
Back & forth between home, 100% city, no highways, lots of traffic light.
Petrol is paying by company, so doesn't care much.  

I floored the pedal almost everyday. Couldn't heal any more, unless my mom on board.

*Note: I change my semi-syn lubs every 5k kms, never missed. Changed spark plug, simota air filter. Guess my car got no problem but my right leg causing FC consumption sky high.

I re-fuel twice a month, so make that roughly 600kms.
You guys 1 tank ran 600kms, me 2 tanks.

I guess that is why it is best to get bodykit from dealer..for me i ask them to install for me,only deduct my discount 1k only..but look very good,no difference between color at all..only regret is after install only i notice cannot install mud guard anymore..