Ls 430 consuming too much fuel
Driver School Candidate
Joined: Jul 2021
Posts: 1
Likes: 0
From: SC
hey did you ever fix this problem can you tell me what it was
Hi guys, i own a ls 430 of the year 2002,
Recently while driving i faced an accelration problem, whenever i pressed the accelerator the car didn't accelerate as it should and it would give me a petrol smell. With that i noticed my petrol guage is decreasing really fast. My range approx decreased 2 km on every half km.
I showed my car to the garage and he cleaned all its fuel filters, catalic, but nothing changed, after that he changed the knock sensors which worked with the acceleration, however my car is consuming the same amount of petrol.
Please can anyone help me with this problem because i cannot pay everything in the gas or to the mechanic.
Recently while driving i faced an accelration problem, whenever i pressed the accelerator the car didn't accelerate as it should and it would give me a petrol smell. With that i noticed my petrol guage is decreasing really fast. My range approx decreased 2 km on every half km.
I showed my car to the garage and he cleaned all its fuel filters, catalic, but nothing changed, after that he changed the knock sensors which worked with the acceleration, however my car is consuming the same amount of petrol.
Please can anyone help me with this problem because i cannot pay everything in the gas or to the mechanic.
Instructor
Joined: Feb 2009
Posts: 1,199
Likes: 214
From: Ontario, Canada
Do everything I listed in my post at https://www.clublexus.com/forums/ls-...l#post10873630 and the acceleration and fuel economy problems should be resolved.
Lexus Champion
Joined: Oct 2019
Posts: 17,910
Likes: 1,702
From: Ohio
They have worked in all cars I have installed them in, the RA denso is good to go in my book and they even chart within 1% or less of an OE one
Last edited by Striker223; Aug 20, 2021 at 05:47 PM.
Pole Position
Joined: Sep 2018
Posts: 265
Likes: 72
From: New South Wales
Ditto. Rock auto denso maf sensor works great for me.
Even If only to prove my original was working perfectly fine anyway.
It came in handy to havie a known good spare when my friends MAF went, so easy to swap and bingo problem solved - night and day
Even If only to prove my original was working perfectly fine anyway.
It came in handy to havie a known good spare when my friends MAF went, so easy to swap and bingo problem solved - night and day
Instructor
Joined: Jan 2018
Posts: 958
Likes: 299
From: WA
Yousaf, see StanVanDam's post # 32 and the link in there. Start with those recommendations. What type of driving are you doing? All in a city, stop and go? There could be many reasons for poor fuel economy including your driving style and what kind of trips you take, which makes a huge difference.
Pole Position
Joined: Sep 2018
Posts: 265
Likes: 72
From: New South Wales
What does your average speed reading say?
How far do you typically drive?
If your driving is normal - your average speed in the trip computer should be somewhere above 35km/h.
The closer you can get it to the sweet spot of 70-80km/h range average the lower your fuel consumption. Above that (then you are lucky to live in a country that you are able to drive fast) your consumption will also start to go up.
During the Covid lockdowns my fuel consumption is high - like 18+l/100km per tank and not uncommon to see higher.
This is because it rarely gets driven more than about 5kms to and from shops to pick stuff up or the park for exercise. The engine is spending a large amount of time warming up, stuck in traffic. This is the worst sort of driving for you car, but we don't have the option for normal or highways driving at the moment so it is what it is.
A tank of fuel still lasts 6 weeks but distance travelled is small. (I also notice it goes through more oil than normal - probably because the engine is spending a lot longer warming up relative to distance travelled).
It is currently reading about 16l/100km and my average speed is 31km/h. The lower the average speed, the higher the fuel consumption
On one tank where we got 18.5l/100 average speed was 22kmh.
Now if your average speed is above 30km/h but below 100kmh average AND your consumption is 22l/100 then it is time to start investigating.
Driver School Candidate
Joined: Sep 2021
Posts: 12
Likes: 5
From: Dubai
Ok so I am assuming you are looking at tank or lifetime average fuel consumption display and not instant....
What does your average speed reading say?
How far do you typically drive?
If your driving is normal - your average speed in the trip computer should be somewhere above 35km/h.
The closer you can get it to the sweet spot of 70-80km/h range average the lower your fuel consumption. Above that (then you are lucky to live in a country that you are able to drive fast) your consumption will also start to go up.
During the Covid lockdowns my fuel consumption is high - like 18+l/100km per tank and not uncommon to see higher.
This is because it rarely gets driven more than about 5kms to and from shops to pick stuff up or the park for exercise. The engine is spending a large amount of time warming up, stuck in traffic. This is the worst sort of driving for you car, but we don't have the option for normal or highways driving at the moment so it is what it is.
A tank of fuel still lasts 6 weeks but distance travelled is small. (I also notice it goes through more oil than normal - probably because the engine is spending a lot longer warming up relative to distance travelled).
It is currently reading about 16l/100km and my average speed is 31km/h. The lower the average speed, the higher the fuel consumption
On one tank where we got 18.5l/100 average speed was 22kmh.
Now if your average speed is above 30km/h but below 100kmh average AND your consumption is 22l/100 then it is time to start investigating.
What does your average speed reading say?
How far do you typically drive?
If your driving is normal - your average speed in the trip computer should be somewhere above 35km/h.
The closer you can get it to the sweet spot of 70-80km/h range average the lower your fuel consumption. Above that (then you are lucky to live in a country that you are able to drive fast) your consumption will also start to go up.
During the Covid lockdowns my fuel consumption is high - like 18+l/100km per tank and not uncommon to see higher.
This is because it rarely gets driven more than about 5kms to and from shops to pick stuff up or the park for exercise. The engine is spending a large amount of time warming up, stuck in traffic. This is the worst sort of driving for you car, but we don't have the option for normal or highways driving at the moment so it is what it is.
A tank of fuel still lasts 6 weeks but distance travelled is small. (I also notice it goes through more oil than normal - probably because the engine is spending a lot longer warming up relative to distance travelled).
It is currently reading about 16l/100km and my average speed is 31km/h. The lower the average speed, the higher the fuel consumption
On one tank where we got 18.5l/100 average speed was 22kmh.
Now if your average speed is above 30km/h but below 100kmh average AND your consumption is 22l/100 then it is time to start investigating.
My machanic told me to change all coils and plugs.
Bcoz in idle my car is little shaking and vibration.
This is 1st time I buy Ls430 and really don't know what can be reason for this poor fuel average.
Instructor
Joined: Jan 2018
Posts: 958
Likes: 299
From: WA
Get the car running properly and follow the suggestions here and of your mechanic. After that, your stop and go in city driving fuel economy might improve some, but not a lot. Its a gas V8 and they get poor mileage in your driving scenario no matter what you do.
Pole Position
Joined: Sep 2018
Posts: 265
Likes: 72
From: New South Wales
Yes my driving is inside city like go and stop. My home to office distance is 18km my average speed is around 26 to 30km/hr. Tank shows 22L/100km and similar fuel average shows around 21 to 22L/100km.
My machanic told me to change all coils and plugs.
Bcoz in idle my car is little shaking and vibration.
This is 1st time I buy Ls430 and really don't know what can be reason for this poor fuel average.
My machanic told me to change all coils and plugs.
Bcoz in idle my car is little shaking and vibration.
This is 1st time I buy Ls430 and really don't know what can be reason for this poor fuel average.
Is there the check engine light?
Usually (but not always) when there is a misfire the check engine light comes on. A check engine light should tell you which cylinder has a misfire if it is specific to just 1 cylinder. OR if it is an intermittent misfire one various cylinders it is probably not the coils and is some other problem.
If you do have a check engine light, do you have a code reader to find out what the codes are? Report back the codes if you do.
As for your mechanics recommendations:
- New plugs yes. Can't hurt as they are a wear item and they are pretty quick and cheap to replace.
I'd probably put a brand new air filter and some fresh oil & filter as a missfire can cause damage to the oil overtime.
- As for the coils - I'd want to to be real sure first that they needed replacing.
They aren't exactly cheap and quite often they get changed when they are in fact in perfectly good operation. There are many other possible causes for misfires - including checking the wiring to the coils and/or potentially stuck/faulty fuel injector amongst others.
How to be sure it is a faulty coil first before just throwing money at it and hoping that is the problem?: (assuming you have new spark plugs and the missfire is still there and there are no check engine light codes)
Step 1. Methodically disconnecting 1 coil pack at a time to see if the missfire get worse. If the coil is working, then the engine will run noticeably rougher everytime you disconnect it.
If there is a misfire that isn't specifically aligned to a coil, then you have an intermittent multiple cylinder misfire - which means it is unlikely that coils are causing it
If there is one cylinder where upon disconnecting the coil there is NO difference (as in the vibration is the same), then that is where the missfire is and we suspect the coil is broken. However to be sure there is one more step.
Step 2: To confirm that the coil is in fact faulty,
Swap that coil with another one. eg if coil on cylinder #2 is suspect then swap it to #3 and put #3 in #2. Then repeat the plug disconnection test on those 2 coils.
If the missfire moved to cylinder 3 and cylinder 2 is working normally - the reverse condition as before - then the coil is in fact the cause and is faulty
However, if the missfire remains on cylinder #2 then the missfire is not spark related and hte cause is something else specific to that cylinder.
If one or more coil pack are infact broken, then you have a choice. Replace the fauly units or replace all of them. I tend to prefer replacing the whole set as when 1 has gone it is likely a matter of time until the rest go. And also make sure to use good quality items - from Toyota, NGK or Denso otherwise you risk swapping one problem for another.
Report back with any additional info. But do start with getting the trouble codes if you have a check engine light
Driver School Candidate
Joined: Sep 2021
Posts: 12
Likes: 5
From: Dubai
Ok so driving use is a factor but the shaking does indicate there is a problem. Likely a missfire of some description as the LS is generally very smooth when everything is running as designed.
Is there the check engine light?
Usually (but not always) when there is a misfire the check engine light comes on. A check engine light should tell you which cylinder has a misfire if it is specific to just 1 cylinder. OR if it is an intermittent misfire one various cylinders it is probably not the coils and is some other problem.
If you do have a check engine light, do you have a code reader to find out what the codes are? Report back the codes if you do.
As for your mechanics recommendations:
- New plugs yes. Can't hurt as they are a wear item and they are pretty quick and cheap to replace.
I'd probably put a brand new air filter and some fresh oil & filter as a missfire can cause damage to the oil overtime.
- As for the coils - I'd want to to be real sure first that they needed replacing.
They aren't exactly cheap and quite often they get changed when they are in fact in perfectly good operation. There are many other possible causes for misfires - including checking the wiring to the coils and/or potentially stuck/faulty fuel injector amongst others.
How to be sure it is a faulty coil first before just throwing money at it and hoping that is the problem?: (assuming you have new spark plugs and the missfire is still there and there are no check engine light codes)
Step 1. Methodically disconnecting 1 coil pack at a time to see if the missfire get worse. If the coil is working, then the engine will run noticeably rougher everytime you disconnect it.
If there is a misfire that isn't specifically aligned to a coil, then you have an intermittent multiple cylinder misfire - which means it is unlikely that coils are causing it
If there is one cylinder where upon disconnecting the coil there is NO difference (as in the vibration is the same), then that is where the missfire is and we suspect the coil is broken. However to be sure there is one more step.
Step 2: To confirm that the coil is in fact faulty,
Swap that coil with another one. eg if coil on cylinder #2 is suspect then swap it to #3 and put #3 in #2. Then repeat the plug disconnection test on those 2 coils.
If the missfire moved to cylinder 3 and cylinder 2 is working normally - the reverse condition as before - then the coil is in fact the cause and is faulty
However, if the missfire remains on cylinder #2 then the missfire is not spark related and hte cause is something else specific to that cylinder.
If one or more coil pack are infact broken, then you have a choice. Replace the fauly units or replace all of them. I tend to prefer replacing the whole set as when 1 has gone it is likely a matter of time until the rest go. And also make sure to use good quality items - from Toyota, NGK or Denso otherwise you risk swapping one problem for another.
Report back with any additional info. But do start with getting the trouble codes if you have a check engine light
Is there the check engine light?
Usually (but not always) when there is a misfire the check engine light comes on. A check engine light should tell you which cylinder has a misfire if it is specific to just 1 cylinder. OR if it is an intermittent misfire one various cylinders it is probably not the coils and is some other problem.
If you do have a check engine light, do you have a code reader to find out what the codes are? Report back the codes if you do.
As for your mechanics recommendations:
- New plugs yes. Can't hurt as they are a wear item and they are pretty quick and cheap to replace.
I'd probably put a brand new air filter and some fresh oil & filter as a missfire can cause damage to the oil overtime.
- As for the coils - I'd want to to be real sure first that they needed replacing.
They aren't exactly cheap and quite often they get changed when they are in fact in perfectly good operation. There are many other possible causes for misfires - including checking the wiring to the coils and/or potentially stuck/faulty fuel injector amongst others.
How to be sure it is a faulty coil first before just throwing money at it and hoping that is the problem?: (assuming you have new spark plugs and the missfire is still there and there are no check engine light codes)
Step 1. Methodically disconnecting 1 coil pack at a time to see if the missfire get worse. If the coil is working, then the engine will run noticeably rougher everytime you disconnect it.
If there is a misfire that isn't specifically aligned to a coil, then you have an intermittent multiple cylinder misfire - which means it is unlikely that coils are causing it
If there is one cylinder where upon disconnecting the coil there is NO difference (as in the vibration is the same), then that is where the missfire is and we suspect the coil is broken. However to be sure there is one more step.
Step 2: To confirm that the coil is in fact faulty,
Swap that coil with another one. eg if coil on cylinder #2 is suspect then swap it to #3 and put #3 in #2. Then repeat the plug disconnection test on those 2 coils.
If the missfire moved to cylinder 3 and cylinder 2 is working normally - the reverse condition as before - then the coil is in fact the cause and is faulty
However, if the missfire remains on cylinder #2 then the missfire is not spark related and hte cause is something else specific to that cylinder.
If one or more coil pack are infact broken, then you have a choice. Replace the fauly units or replace all of them. I tend to prefer replacing the whole set as when 1 has gone it is likely a matter of time until the rest go. And also make sure to use good quality items - from Toyota, NGK or Denso otherwise you risk swapping one problem for another.
Report back with any additional info. But do start with getting the trouble codes if you have a check engine light
This is total KM in one fuel tank approx 370km and check engine sign is coming. It shows 22.4L/ 100km.