Nairaland Forum

Welcome, Guest: Join Nairaland / Login / Trending / Recent / New
Stats: 1262166 members, 1709936 topics. Date: Thursday, 30 October 2014 at 03:29 PM

What Causes A Car To Start Consuming Fuel Excessively - Car Talk - Nairaland

Nairaland Forum / Nairaland / General / Car Talk / What Causes A Car To Start Consuming Fuel Excessively (55343 Views)

What Causes Overheating And How Can It Be Totally Prevented / HELP: My Car Is Consuming Too Much Fuel. / My Car Is Consuming Water At A Rapid Rate (1) (2) (3) (4)

(0) (1) (2) (3) (Reply) (Go Down)

What Causes A Car To Start Consuming Fuel Excessively by pak: 10:14am On Nov 14, 2011
I have a car with a 3.0L engine. though the fuel consumption has always been on the high side,

however of recent, the fuel consumption has shot to the roof.


It now guzzles fuel like no man's business.

I've had to service the car, the mechanic requested that the spark plugs be changed, which I did.

But the situation hasn't improved considerably.

Now the mech is suggesting I change/service the fuel injector and the exhaust.


Please, I wish i can get expert advice on this cos am quite scared of this trial and error method from Nigerian Mechs.


What do you think caused this and what are the suggestion as regards resolving the problem.

By the way, the car is a Honda Accord EOD 2003 model




NOTES 2013
Alleluya ! My two year old thread finally made frontpage.
Though, I've gotten another car anyway (a second alleluya, pls)
and it seems oga Sienna is no longer following the thread.

For Posterity sake, the two problems I had was
1. Using bigger tyres than the recommended size, as stated below
2. My Mechs put water inside the radiator instead of coolant after servicing, leading to the engine operating at a higher temperature than normal.
Good thing is the car is still on the road, still ran around town with it today.

5 Likes

Re: What Causes A Car To Start Consuming Fuel Excessively by pak: 7:43pm On Nov 14, 2011
. . . . still waiting for your advice.

Thanks
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 11:02pm On Nov 14, 2011
Things that can make a car thirstier than normal:

01) Dirty / clogged air filter.
02) Incorrect ignition timing. *
03) Under-inflated tyres (higher rolling resistance).
04) Binding brakes.
05) Leaking fuel injectors.
06) Blowing exhaust system.
07) Faulty MAF (mass air flow meter).*
08) Faulty CTS (coolant temperature switch).*
08) Faulty o2 sensor (Lambda).*
09) Thermostat stuck open, or removed by some dodgy mechanic. Over cooled engine.
10) Split / perished vacuum hoses, engine drawing in unmetered air.*

I would suggest an OBD scan, your '03 Honda Accord is fully OBD II compliant. All the items marked with an asterisk will normally trigger an engine check light (CEL). It would help too, if you can recall when you noticed the higher than normal fuel consumption. Did it occur after any work was carried out on the car? The thermostat is an area I would look into - if it's stuck open (or it's been removed) the engine will never reach its optimum operating temperature. The CTS will sense the engine is not hot, and the ECU will send more fuel through the injectors as a result. This is done by altering the duty cycle (the amount of time the injectors are held open will be longer).

Tyre pressures are also important, if the pressures are too low, the rolling resistance will place more load on the transmission, then the engine will work harder. The same goes for brakes that are binding (sticking on).

15 Likes

Re: What Causes A Car To Start Consuming Fuel Excessively by pak: 8:18am On Nov 22, 2011
@Sienna

Thanks a million for your input. I really do appreciate it.
And sorry for the late response been out of town for a while.

Anyway, am heading to mechanic this morn and am going to insist on an OBD scan before he touches mine.

Am about to order a scanner myself (but should arrive december).



As for when I noticed it.

I decided to change my two front tires, the specs that initially came with the car are 205/60R/16

but at the Pirelli shop, they had only a 205/65R/16C. The service guys said the difference btw the two

was very minimal and not willing to buy the less reliable local ones, I purchased them (could that be the problem ?)

And also while carrying out the alignment and wheel balancing, I was adviced to change two of the low arms at the back wheel,

which I did.

Well, the next day, I took the car on a a journey and suddenly started noticing that the car was guzzling fuel at an extraordinary rate.




Thanks and I'll let you know how it goes.
Re: What Causes A Car To Start Consuming Fuel Excessively by kuntash: 9:05am On Nov 22, 2011
how their reasons disgust me in a bid to carry out action cause nos -9 listed by Siena

@ poster, the engine needs to be hot to a certain level for effective combustion of fuel
Re: What Causes A Car To Start Consuming Fuel Excessively by jdiadem: 9:24am On Nov 22, 2011
@ poster,

i think the tire change might be part of it, the engine now have a greater tire surface area to roll on and that definitely will affect the fuel consumption as i've experienced same too especially as it will raise the front a little higher previously.
i'd suggest if your back tires are good, you change them to the front and the new ones to the back.
Re: What Causes A Car To Start Consuming Fuel Excessively by Trac: 3:42pm On Nov 22, 2011
In addition to all that has been said, consider the weight of oil used. If intended denotes 20 or 30 weight oil and you fit in 20w-50 or something in that order, you re going to have parasitic drag in your chamber. The oil is too heavy and driveability suffers. Consider fuel treatment/stabiliser also and your source of fuel purchase. You can control and slowly eliminate port fuel deposits by using these treatments every month. If the gasoline sold where you are contains ethanol, in the long run, your vehicle will trap in moisture in the gas chamber that might eventually lead to water. You can figure what might happen over an extended period of time.

2 Likes

Re: What Causes A Car To Start Consuming Fuel Excessively by jdiadem: 3:51pm On Nov 22, 2011
[font=Lucida Sans Unicode]In addition to all that has been said, consider the weight of oil used. If intended denotes 20 or 30 weight oil and you fit in 20w-50 or something in that order, you re going to have parasitic drag in your chamber. The oil is too heavy and driveability suffers. Consider fuel treatment/stabiliser also and your source of fuel purchase. You can control and slowly eliminate port fuel deposits by using these treatments every month. If the gasoline sold where you are contains ethanol, in the long run, your vehicle will trap in moisture in the gas chamber that might eventually lead to water. You can figure what might happen over an extended period of time.[/font]


i thought some experts said we don't actually need any form of treatment (fuel or engine oil) that it destroys the engine.
can someone clarify this - Siena, what's your take on this.

1 Like

Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 4:32pm On Nov 22, 2011
pak:

I decided to change my two front tires, the specs that initially came with the car are 205/60R/16

but at the Pirelli shop, they had only a 205/65R/16qef. The service guys said the difference btw the two

was very minimal and not willing to buy the less reliable local ones, I purchased them (could that be the problem ?)

Here lie your problems. There are two problems here: Tyre size and speed rating.

You've gone from 205/60x16H to 205/65x16C The maximum permissible difference when up-sizing or down-sizing tyres to maintain correct aspect ratio is 2,5%. The difference between your original tyres and the ones you've fitted is now 3,22%.

205/60x16 = 25,7" (652 mm)
205/65x16 = 26,5" (673 mm)

Using tyres with a larger diameter makes your car gearing higher. This effectively means your second gear will feel like third. So when pulling away from standstill, your engine will work harder to overcome inertia. At any given speed below highway speeds, you'll be driving with more gas to achieve the same speed. On the highway, the higher gearing will make your car better on fuel, as your larger wheels have effectively given your car an "overdrive". That's all things being equal, which they're not[i].[/i]..

You've also gone fro a H speed rating to a C. H is rated up to 130 mph (210 km/h) which the Honda Accord 3,0 V6 is certainly capable of. Your new C rated tyres are NOT meant for any passenger cars. C denotes "Commercial" and a 205/65x16C is normally found on a Ford Transit or Mercedes-Benz Sprinter. These tyres have thicker side walls and tread, and they are way too heavy for passenger cars. Even if the size is the same as your originals, the construction means you've got more inertia issues when pulling from stand still.

C rated tyres are not designed for the speeds a regular car will attain, and the risk of blow-outs at sustained high speed (over 200 km/h) is an issue. Shocking that any tyre stockist wouldn't have advised you the risks and other draw backs.

So as a re-cap:

Excessive inertia from standstill due to larger diameter.
Excessive inertia from standstill due to 6-ply heavy construction (commercial uses only).

Replace them with the CORRECT size and speed rating (H or V) and you'll notice your fuel consumption will improve dramatically.

11 Likes

Re: What Causes A Car To Start Consuming Fuel Excessively by pak: 8:47am On Nov 23, 2011
WOW, gee that was deep.

I did the diag yesterday and the two results I got were nthing I presume can affect Fuel performance

1. Solenoid IVTEC valve
2. Circuit high Voltage.


The Diag guy then suggested I check the exhaust system.

but with this, i think I'll just change the tyres and then see out it goes.

I should be travelling tommorow, so I guess it will be another good opportunity to test.


Thanks once again Sienna, you the best.
Re: What Causes A Car To Start Consuming Fuel Excessively by seyiogundipe: 8:50am On Nov 23, 2011
Whao!!! Siena, you are the bomb.
3 things intrigue me namely
1. Spirituality & God
2. Wits/talents/knowledge/intellects
3. Human relationship's dynamics esp the intricacies of human's heart.
You eschewed too much wits here for this thread.
I'm proud of you.
By the way, could you kindly give me a rundown on what you do, your educational stints etc @ seyiogundipe@yahoo.com
Please as a low-income earner with prospects in future wishing to own his 1st car, which car under 850k naira would you recommend for me minding comfort, cost of maintenance, ease of maintenance etc
Have a nice day.
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 12:39am On Nov 29, 2011
seyiogundipe:

Whao!!! Siena, you are the bomb.
3 things intrigue me namely
1. Spirituality & God
2. Wits/talents/knowledge/intellects
3. Human relationship's dynamics esp the intricacies of human's heart.
You eschewed too much wits here for this thread.
I'm proud of you.
By the way, could you kindly give me a rundown on what you do, your educational stints etc @ seyiogundipe@yahoo.com
Please as a low-income earner with prospects in future wishing to own his 1st car, which car under 850k naira would you recommend for me minding comfort, cost of maintenance, ease of maintenance etc
Have a nice day.

Sorry bud, I've only just spotted your post. I'll email you in the next couple of days.
Re: What Causes A Car To Start Consuming Fuel Excessively by kuntash: 5:07am On Nov 29, 2011
hmmmm, tyre matter na serious issue o
Re: What Causes A Car To Start Consuming Fuel Excessively by yusuf2(m): 5:58am On Nov 29, 2011
Op, i use the same type of car as u, accord 03' v6. I can confirm that d tyre change is what has caused your car to suddenly start to burn more fuel. I as well just changed my 2 front tires from 215/65/16 specs to 215/60/16 specs, d width reduction did a magic of reducing d amount of fuel my car burns, can't xplain! i wasn't intending to change d back ones anytym soon but with dis new realization i wld definitely change them to same specs as d front once cos i'll be happy to c my ride burn less fuel! So "fresh air government, go ahead & remove fuel subsidy, i'm waiting at d other side"
Re: What Causes A Car To Start Consuming Fuel Excessively by cretin: 6:12am On Nov 29, 2011
@siena, pls cud u confirm if this tyre config will damage my car, n if yes, what exactly?.

i use 225/70/r16 on all my 4 tyres [thats what it came with], then 1 of the front tyres got bad and i replaced it with the spare, which is 215/70/r16.


pls educate me if this is wrong.

also, i ran into a curb the other day, and went for alignment/balancing n the guys said the rim is badly bent, that it cant be balanced, though physically, i cant seem to see anything, isnt there a way of bending it back to shape?, [note its alloy rim]
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 9:42am On Nov 29, 2011
cretin:

@siena, pls cud u confirm if this tyre config will damage my car, n if yes, what exactly?.

i use 225/70/r16 on all my 4 tyres [thats what it came with], then 1 of the front tyres got bad and i replaced it with the spare, which is 215/70/r16.

pls educate me if this is wrong.

also, i ran into a curb the other day, and went for alignment/balancing n the guys said the rim is badly bent, that it cant be balanced, though physically, i cant seem to see anything, isnt there a way of bending it back to shape?, [note its alloy rim]

Mr C, what make and model is your car?
Re: What Causes A Car To Start Consuming Fuel Excessively by cretin: 10:07am On Nov 29, 2011
@siena, the car in question is a 2003 rav4 auto 4wd
Re: What Causes A Car To Start Consuming Fuel Excessively by leke999(m): 10:56am On Nov 29, 2011
SIENA,
So in luv with u.should u manufacture ur own car plz let me know-one customer in the waiting.lets talk,i have issues with my 1999 baby boy.ichehoke@yahoo.co uk.BB 21207E9D.plz write me.

1 Like

Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 11:47am On Nov 29, 2011
cretin:

@siena, the car in question is a 2003 rav4 auto 4wd

The tyre size you've chosen isn't an issue. What would be an issue long-term is mixing different size tyres on the same axle. Your car is AWD, so you can't run different size tyres, otherwise you'll destroy the transfer box / differential.

The smaller wheel will turn at a faster rate to the larger ones, and on dry surfaces, you'll be scrubbing your tyres at a rapid rate, and of course your differential will constantly be trying to compensate for the different speeds, it will be worse when turning corners. At constant speeds in a straight line, with different tyre sizes, the differential / transfer box can actually explode, due to excessive heat build-up and hydraulic pressure.
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 11:50am On Nov 29, 2011
leke999:

SIENA,
So in luv with u.should u manufacture your own car plz let me know-one customer in the waiting.lets talk,i have issues with my 1999 baby boy.ichehoke@yahoo.co uk.BB 21207E9D.plz write me.

I'm old skool, so don't have a Blackberry, lol. My email address is siena_@hotmail.co.uk

Or you can post your query here, if you wish.
Re: What Causes A Car To Start Consuming Fuel Excessively by blacksta(m): 11:54am On Nov 29, 2011
Siena

Have you ever shipped car parts from Uk to Nigeria - if so was it land or Sea and what was the experience like

Thanks
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 12:27pm On Nov 29, 2011
blacksta:

Siena
Have you ever shipped car parts from Uk to Nigeria - if so was it land or Sea and what was the experience like
Thanks

I ship regularly. I tend to use air freight for new parts, and sea for larger consignments of used spares, which tend to include engines, transmissions, axles, suspension and other bulky items.
Re: What Causes A Car To Start Consuming Fuel Excessively by blacksta(m): 12:53pm On Nov 29, 2011
Siena:

I ship regularly. I tend to use air freight for new parts, and sea for larger consignments of used spares, which tend to include engines, transmissions, axles, suspension and other bulky items.

Would you be happy to guide me through the process. I am planning on getting some parts for a vehicle i bought in the states shipped from UK to the Nigeria. Thanks

1, is the service door to door
2, what is the typical cost e.g a car battery
3 Can i send engine oil?
4 Do you pay extra duty once it reaches Nigeria

1 Like

Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 1:26pm On Nov 29, 2011
blacksta:

Would you be happy to guide me through the process. I am planning on getting some parts for a vehicle i bought in the states shipped from UK to the Nigeria. Thanks

1, is the service door to door
2, what is the typical cost e.g a car battery
3 Can i send engine oil?
4 Do you pay extra duty once it reaches Nigeria

Sure, I'm happy to talk you through the process, feel free to shoot me an email, I'll attend to it later: siena_@hotmail.co.uk
Re: What Causes A Car To Start Consuming Fuel Excessively by atasteve: 1:38pm On Nov 29, 2011
Lord Siena, you have thoroughly treated this case.

What scanning tool will you advise for private use for Toyota, Honda and Nissan models.
Re: What Causes A Car To Start Consuming Fuel Excessively by blacksta(m): 11:08am On Dec 13, 2011
Siena you have mail

1 Like

Re: What Causes A Car To Start Consuming Fuel Excessively by dirotula: 3:17pm On Dec 13, 2011
Siena, that was a very good justice you did to that topic, nice 1 man,

However, i have a similar issue with my HONDA CR-V 2002 model, got it like a year 6 month ago, but i recently discovered that the fuel consumption is high after i went on a trip to Akure from lagos, when i complained to my auto mechanic, he did a check on it and told me a catalyst in the exhaust system has been removed, (Probably before i bought the car from the dealer) that is the cause of the high fuel consumption, he said i need to replace the catalyst and the problem will be solved.

How true is that?

Am presently thinking of doing just that, but i need your expert opinion on this before i comit myself, as i don't really trust most of these machanics around.

Thanks for your anticipated response.
Re: What Causes A Car To Start Consuming Fuel Excessively by Siena(m): 3:33pm On Dec 13, 2011
If you'd had your SUV for 6 months, and fuel consumption seemed pretty normal, I doubt a catalyst that was removed before you bought the vehicle would be the culprit. Catalysts are generally restrictive, and actually increase fuel consumption marginally. It also limits power, which is why some owners in enthusiast circles do a catalyst delete.

The issues that removal could cause depend if the vehicle is OBD-II (which means oxygen sensor AFTER the catalyst, as well as before). An OBD-II vehicle will have issues if the catalyst is removed, as the O2 sensor after the missing catalyst will be measuring a different gas composition and flow rate. There are ways round this, one is to map out the function of the secondary O2 sensor, (not practical in Nigeria) or modify the O2 sensor bung, so the tip is spaced out from the gas flow.

But as always, I would recommend a scan, as I'm not entirely convinced a catalyst that's been missing since you bought the car, is the issue here. A dead MAF or faulty O2 sensor are the most common and likely culprits (if I would hazard a guess).
Re: What Causes A Car To Start Consuming Fuel Excessively by dirotula: 6:28pm On Dec 13, 2011
Thanks Siena, really appreciate your well articulated view, i think i will go for the scan,


Anybody that can recommend a very good car scaning center in Lagos i will appreciate that.
Re: What Causes A Car To Start Consuming Fuel Excessively by Gelatoman: 10:45am On Jul 25, 2012
Hello Siena,


Your contribution in the forum is priceless.

I drive Toyota Avensis 2005. After 6months of using this car i suddenly noticed that it consumes fuel more than Vampire consume blood. I have serviced the injector and nozzle. The silencer does not emit black smoke. My mechanic said the catalyst has been removed which is the cause. I argued this with him cause I only noticed this after six month and the car has never slept in mechanic workshop for a day. What do you suggest?

Also, 3 of my tires are 195/65 and the 4th one is 205/60....can this also cause high fuel consumption?


Many thanks

1 Like

Re: What Causes A Car To Start Consuming Fuel Excessively by gulfer: 11:33am On Jul 26, 2012
Gelatoman: Hello Siena,


Your contribution in the forum is priceless.

I drive Toyota Avensis 2005. After 6months of using this car i suddenly noticed that it consumes fuel more than Vampire consume blood. I have serviced the injector and nozzle. The silencer does not emit black smoke. My mechanic said the catalyst has been removed which is the cause. I argued this with him cause I only noticed this after six month and the car has never slept in mechanic workshop for a day. What do you suggest?

Also, 3 of my tires are 195/65 and the 4th one is 205/60....can this also cause high fuel consumption?


Many thanks
If you read Sienna's reply up the post you'll do well to start by getting all the tires to the same size and use the right psi. See if you get an improvement after that.
Re: What Causes A Car To Start Consuming Fuel Excessively by Chynx(m): 7:11pm On Jul 27, 2012
Nice one Siena. You ar too good!
Kindly advise me on this issue:
My car (Nissan Altima 2.5s 2002 model) no longer accelerates as usual. When driving normally, it always drags when I try to move faster except I step hard on d gas pedal then I get this roar and subsequent surge 4wrd with serious muscle.
I have serviced d injector, changed d fuel pump and washed d fuel filters, yet no improvement has been noticed. In addition, my car no swallows fuel more than I gozzle beer. Your professional advice will be very much welcome.

2ndly, I have always suffered dis noise from d front legs each time t drive on rough surfaces like inter-locking tiles. I have changed my 4 shock absorbers, lower arms and thyroids and painfully, d noise hasnt stopped.

Please help me out on this.
My email is c4mine@yahoo.com
May God bless u.

1 Like

(0) (1) (2) (3) (Reply)

Right Hand Drive (RHD) To Left Hand Drive (LHD) Conversion / Nairaland Auto Show- With Pictures. / Pictures: Presidency Officials Now Use Innoson Suv's

Viewing this topic: 1 guest(s)

(Go Up)

Sections: politics (1) business autos (1) jobs (1) career education (1) romance computers phones travel sports fashion health
religion celebs tv-movies music-radio literature webmasters programming techmarket

Links: (0) (1) (2) (3) (4) (5) (6) (7) (8) (9)

Nairaland - Copyright © 2005 - 2014 Oluwaseun Osewa. All rights reserved. See Nairalist and How To Advertise. 141
Disclaimer: Every Nairaland member is solely responsible for anything that he/she posts or uploads on Nairaland.