Do Not Sell My Personal Information Jump to content


Important Advice For Those Who Have A Higher Mileage Gs300


Recommended Posts


  • Replies 64
  • Created
  • Last Reply

Top Posters In This Topic

Can I ask why you shouldn't use Slick 50?

I realise there is no need now we have synthetic oil, but I used to use it in the 80s when it first came over here-never had any trouble. That was when you put it in your engine and ran it for 20 mins then drained it and did your oil & filter change.

Link to comment
Share on other sites

I can go into great detail but i wont........ yet.

Basically slick 50 is loads of tiny particles of plastic in your engine, it can ware components, clog the oil fitter and it will tend to just sit in the lowest pressure parts of the oil system.

There is evidience to back this up in the form of independant tests.

Also slick 50's idea is meant to give a teflon coating to your engine right? thats the whole benefit.

Well the teflon coating ptfe id made and sold to slick 50 by DuPont.

DuPont have publicy said slick 50's claims are totaly false and its impossible, they were (or may still be) in a legal battle with slick 50 to remove all reference of teflon or ptfe from the product and be allowed to stop suppling them.

My uncle is a race engineer and advised me against this when i had the idea, i then researched it and its all bad i assure you.

I have a big thread on my forum i will try and dig out.

Heres what i was looking for... read this if you still want to use or do use slick 50:

http://www.repairfaq.org/filipg/AUTO/F_Slick_501.html

Link to comment
Share on other sites

Depends how it is configured, if the fueling is controlled by the stock ECU then yes. or if the new ECU is wired upto the lambda sensors then yes. Im not really sure how LPG is fitted to be honest.

Its just open loop and closed loop. If your o2 sensors are goosed they will either provide false readings or the ECU wont use them to determine how to adjust the fueling at all it will just use the lookup tables on the ECU. This is never spot on as its just a generic set.

Hence you loose bhp and mpg.

I wouldn't go more than 30k without giving them a check and clean at least. They are relativley cheap, easy to check / replace and really do make a dramatic impact on the running on the car.

If your cars obd 1 then you can test them with a blowtorch and a multimeter but it may just be better to buy new ones :)

Have a look at this... I did a search for my 1993 Mk1 and this is what I found.

http://www.automedicsupply.com/catalog.php...3.0L+exc.+Calif.

They charge $25 to ship to the UK but with the dollar being as weak as it is it makes for a good deal

A look at the car Iand I can see 2 sensors 1 under the air intake and 1 on the exhaust downpipe. So Iam assuming there are only 2. They both appear to be single wire types so should be, rust permitting, easy to replace.

By the way my mpg has improved quite a bit for the sake of a new air filter!!! Well worth the 18 Quid!!!

Link to comment
Share on other sites

I believe there are three oxygen sensors on the Mk1 GS one for each bank of three cylinders at the manifold referred to as the 'main' sensors accessible from within the engine bay and one that is referred to as a 'secondary' sensor connected somewhere near the exhaust CAT but accessible from under the drivers side footwell carpet IIRC.

Colin will correct me no doubt if I am wrong and let us know precisely where they are located..

Link to comment
Share on other sites

Have a look at this... I did a search for my 1993 Mk1 and this is what I found.

http://www.automedicsupply.com/catalog.php...3.0L+exc.+Calif.

They charge $25 to ship to the UK but with the dollar being as weak as it is it makes for a good deal

A look at the car Iand I can see 2 sensors 1 under the air intake and 1 on the exhaust downpipe. So Iam assuming there are only 2. They both appear to be single wire types so should be, rust permitting, easy to replace.

By the way my mpg has improved quite a bit for the sake of a new air filter!!! Well worth the 18 Quid!!!

Excellent find and with the amount of miles I inflict on mine (approx 500/week :crybaby: ) I will definitely be investing in some replacements.

Link to comment
Share on other sites


Hmm, thats got me wondering now, I get approximately 21mpg out of my lexus, and have done for a while, she's a thirsty beast, but regardless of how you drive it its alwas about 21mpg returned, I get 280 miles per tank if I'm lucky. My car is a 1997 P reg GS300 sport (Mk 1) and I thought it used to get higher mileage than that... so do you think a new pair or 3 oxygen sensors might bring my fuel efficiency back up? If so I might not sell her afterall.

Paul

Link to comment
Share on other sites

Hmm, thats got me wondering now, I get approximately 21mpg out of my lexus, and have done for a while, she's a thirsty beast, but regardless of how you drive it its alwas about 21mpg returned, I get 280 miles per tank if I'm lucky. My car is a 1997 P reg GS300 sport (Mk 1) and I thought it used to get higher mileage than that... so do you think a new pair or 3 oxygen sensors might bring my fuel efficiency back up? If so I might not sell her afterall.

Paul

well craig wrote earlier in the thread that he gets 450 from his mk1 sport, so something is wrong. you need to pull them out and give them a check

Link to comment
Share on other sites

How can I check them easily? I haven't got access to an oscilliscope as mentioned earlier, I'm sure I can use a multimeter, but not sure how to do that since you mentioned voltage not resistance. If the ecu had a code suggesting the sensors were gone would I get an engine check light on all the time? I presume that if they are inefficient the ecu doesn't always let you know?

Paul

Link to comment
Share on other sites

Yes Keith, you are right

2 on exhaust manifold, 1 under carpet, just looked at manual :)

according to the manual ;)

heres the figures

@ 20c (68f) all sensors should have a resistance of between 11.7-14.3 ohms

(+B and HT)

if not between them figures replace sensor

Steve,

*edit*

just been out today, had a look, all mine are single wire sensors, so , info not really much use, looks like usa and uk cars have different ones on

Link to comment
Share on other sites

Guys

just done a steady motorway trip unladen with the criuse set at 70 in light to moderate traffic. got 200miles from brim filled tank to half a tank on the gauge.....what do you think i recon this is about 21mpg should it be much better from my 96 Gs300 sport with 96K on the clock?

Link to comment
Share on other sites

Guys

just done a steady motorway trip unladen with the criuse set at 70 in light to moderate traffic. got 200miles from brim filled tank to half a tank on the gauge.....what do you think i recon this is about 21mpg should it be much better from my 96 Gs300 sport with 96K on the clock?

You cant tell until you brim it again.Did Coventry/Gatwick and back couple of weeks ago 2 adults and luggage...brim filled b4 and after....27mpg at "around"the legal limit.Coventry/Lyme Regis return this week 2 adults,bit of local running too and got around 29mpg.Mine has 134K on it.

Link to comment
Share on other sites

  • 2 weeks later...

This may be of interest...

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...8965&rd=1,1

eBay item 190058148965

I have just bougt 3 universal O2 Sensors with flanges from this guy. His eBay feedback is good and I contacted him to confirm that the are the right ones for a 1993 GS300 and will fit all 3 positions. His got back to me very quickly and seems very knowledgable.

It is worth contatcing him becuase he gave a discount on shipping for buying multiple items.

All 3 cost me £33.61 including p&p from the States ($18.00 x 3 = $10.00 P&P) :D

It Should take a week or so before they arrive so I'll keep you posted

Simon :D

Link to comment
Share on other sites


I have reviewed my fuel costs after 11,000 miles in my GS. Average mpg works out at 20mpg, which is lower than what it should be.

Have serviced the car, no check engine lights have appeared. Everything appears to be in order.

I got my codes read on Saturday, turns out my oxygen sensors are :tsktsk:

Worn oxygen sensors lead to poor mpg (up to 30% more fuel used), and poor performance. They can wear out after just 60-70k miles. Mine is now 95k.

Darn Maneesh, I think you've jinxed me! :)

Not a week after I read your post the engine malfunction light on my 2001 GS430 Sport came on for the first time since I've owned it. The car was driveable but I noticed it was rather sluggish on acceleration and the average mpg was around 17 mpg. Also in cold temperatures the exhaust smoked massively.

I took it in to my friendly Lexus main dealer who diagnosed a faulty oxygen sensor. This has been replaced and the car is back to its old self - acceleration similar to the space shuttle and the huge billowing clouds of exhaust smoke in cold weather seem to be gone (touch wood).

I wish I was skilled and confident enough to change the O2 sensor on my own though - it would have saved me a fortune :(

BTW - As a previous owner of a Ford Granada Cosworth, I thought that its 0-60 acceleration was phenomenal, the GS430 is in a completely different league however. When you floor the pedal the engine roar and the resultant acceleration is simply phenomenal :)

Seasons greeting to all

Peter

Link to comment
Share on other sites

This may be of interest...

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...8965&rd=1,1

ebay item 190058148965

I have just bougt 3 universal O2 Sensors with flanges from this guy. His ebay feedback is good and I contacted him to confirm that the are the right ones for a 1993 GS300 and will fit all 3 positions. His got back to me very quickly and seems very knowledgable.

It is worth contatcing him becuase he gave a discount on shipping for buying multiple items.

All 3 cost me £33.61 including p&p from the States ($18.00 x 3 = $10.00 P&P) :D

It Should take a week or so before they arrive so I'll keep you posted

Simon :D

This may be of interest...

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...8965&rd=1,1

ebay item 190058148965

I have just bougt 3 universal O2 Sensors with flanges from this guy. His ebay feedback is good and I contacted him to confirm that the are the right ones for a 1993 GS300 and will fit all 3 positions. His got back to me very quickly and seems very knowledgable.

It is worth contatcing him becuase he gave a discount on shipping for buying multiple items.

All 3 cost me £33.61 including p&p from the States ($18.00 x 3 = $10.00 P&P) :D

It Should take a week or so before they arrive so I'll keep you posted

Simon :D

They Arrived today - I'll have a go at the weekend to fit them!!! ;D

Link to comment
Share on other sites

This may be of interest...

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...8965&rd=1,1

ebay item 190058148965

I have just bougt 3 universal O2 Sensors with flanges from this guy. His ebay feedback is good and I contacted him to confirm that the are the right ones for a 1993 GS300 and will fit all 3 positions. His got back to me very quickly and seems very knowledgable.

It is worth contatcing him becuase he gave a discount on shipping for buying multiple items.

All 3 cost me £33.61 including p&p from the States ($18.00 x 3 = $10.00 P&P) :D

It Should take a week or so before they arrive so I'll keep you posted

Simon :D

This may be of interest...

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...8965&rd=1,1

ebay item 190058148965

I have just bougt 3 universal O2 Sensors with flanges from this guy. His ebay feedback is good and I contacted him to confirm that the are the right ones for a 1993 GS300 and will fit all 3 positions. His got back to me very quickly and seems very knowledgable.

It is worth contatcing him becuase he gave a discount on shipping for buying multiple items.

All 3 cost me £33.61 including p&p from the States ($18.00 x 3 = $10.00 P&P) :D

It Should take a week or so before they arrive so I'll keep you posted

Simon :D

They Arrived today - I'll have a go at the weekend to fit them!!! ;D

Be sure to let us know the results :winky:

Link to comment
Share on other sites

Interesting post. Does anyone know if the Is300 is prone to this issue also ? I'm getting abount 300 miles from a tank.

It has the same engine and any vehicle with a three way cat depends on the O2 sensors however the sensors should be good for 60k to 100k miles before needing to be checked/cleaned/replaced.

Link to comment
Share on other sites

Now it's been a long time since I got my hands dirty under the bonnet but what a doddle of a job:D

All you need is a 12mm socket and a 3inch extention bar - mine came out of a £2.99 socket set I bought from a car booty!!

Just move the air hose to gain good access to the o2 sensor by loosning a few jubillee clips and shoving it out of the way. Undo the 2 12mm nuts holding it in - mine came off mercifully easily - the disconnect the electrical connector and that's it - the old one is out.

I then cut the connector from the old o2 sensor and spliced it onto the new one using terminal block aand loads of insulting tape.

Fitting is the reversal of the above and just as easy!!

To do both of the ones in the engine bay took me about an hour - and that's including a cup of tea!!

I then run the car for a few minutes half expecting the Engine Warning Light to come on but all I got was the grey-ish exhaust smoke that use to be, disappear as the car warmed up - it looks like they are working!!

Please folks don't wimp out and pay Lexus a fortune for this - if you can change a light bulb you can do this job. I paid £33 for 3 universal o2 sensors that came from the US in a week (over the Christmas period). It costs more than this for Lexus to tell you that they need changing. So for me this is a no-brainer - just do it!!

Now I am sure there are some lucky ones on this site who have fat cat salaries and can afford to pay the dealers but for us mere mortals we can learn a thing or two from the BMW fraternity and start doing a few jobs like this and save a fortune.

So this afternoon I'll see if I can find the last sensor!! - Under the carpet I believe!!

Link to comment
Share on other sites

Have serviced the car, no check engine lights have appeared. Everything appears to be in order.

I got my codes read on Saturday, turns out my oxygen sensors are :tsktsk:

Worn oxygen sensors lead to poor mpg (up to 30% more fuel used), and poor performance. They can wear out after just 60-70k miles. Mine is now 95k.

Replacing oxygen sensors is a DIY job, and I'm buying mine from the US for 30 quid each.

I feel like such a stupid person, as I've spent £750 MORE on petrol this year, that I didn't need to, if I had pulled the codes when I bought the car.

Learn from my experience, and if you're driving an older GS (or even LS), get your diagnostic codes checked to see if your oxygen sensors are worn out..could save you a packet in petrol!!!

EVERYBODY PLEASE HELP, CHECK ENGINE LIGHTS

I've got a 1994 GS 300, with a lot of kms. 220,000 kms! Just recently I've been having the check engine warning lights come up (in the owner's manual they call it the 'Malfunction Indicator Lamp') And I've also got the TRAC OFF sign, also know as 'Traction Control System OFF Indicator/Warning Light' in the owenrs manual.

We haven't been driving it much ever since they've both come on. But it drives smooth as ever, no noise, no nothing. Do you think I've got to check diagnostics codes check to see if my Oxygen Sensor are worn (get it checked by Lexus dealership, or any repair shop...BETTER YET I HOPE TO REPLACE OXYGEN SENSOR MYSELF TO SAVE$$$)???

Oh yes, I must say, it cost me around 65 to 70$ Canadian to get the fuel tank full. Is that a sign of some sort???

-Amber

Link to comment
Share on other sites

I'm gonna take the plunge but I deffo wont be having a cup of tea or sneezing when I fit them.

My car has been transformed since I changed the Air flow meter thingy but I did clean the whole intact tract out as well.

I have worked out that I have only done just under 1100 miles in it since Boxing day 2005 when I changed the timing belt and wrote the details down. The low mileage hasn't helped but its in for a good hammering when the sensors get swapped to see if makes a bigger difference.

Link to comment
Share on other sites

I have a 1997 MK1 Lexus GS300. I got 19 miles to the Gal on last fill up :-( about 280 to the tank.

I think i have the o2 sensor problem, however, i need some advice.

Do I buy universal sensors and splice them in?

Or spend a bit more and get the ones with the correct clips...

Also how do I test/clean the existing sensors.... a blow torch????

Can someone tell me what to look for to find the sensors.

cheers

:-)

Link to comment
Share on other sites

I Just spoke to the Lexus Garage.

The sensors cost £141.15 for the front and £185.73 for the back!!!!

Plus 1 and 1/2 hours labour.

The guy advised me to first disconnect the Battery for about 1/2 hour.

The GS300 has a self learning ECU. Thus if you bought yours second hand, and the last driver was a slow lane driver, the ecu could do with a reset and thus the 1/2 Battery disconnect.

I'm gonna try that first. If this doesnt work I will have to order the sensors.

Link to comment
Share on other sites

I Just spoke to the Lexus Garage.

The sensors cost £141.15 for the front and £185.73 for the back!!!!

Plus 1 and 1/2 hours labour.

You do realise the sensors can be ordered from the States at a much cheaper price, and it's a job that you can do at home? All the info can be found in earlier posts in this very thread.

Link to comment
Share on other sites

I Just spoke to the Lexus Garage.

The sensors cost £141.15 for the front and £185.73 for the back!!!!

Plus 1 and 1/2 hours labour.

You do realise the sensors can be ordered from the States at a much cheaper price, and it's a job that you can do at home? All the info can be found in earlier posts in this very thread.

Yeah I saw on this forum. I was just amazed at how much Lexus was charging. If the ECU reset doesnt work I will order them.

I am not sure what to get. Do i spend about £100 plus P and P and get the sensors with the correct connectors, or do I spend £45 plus p and p and get the univesal sensors??

Is the save of £45 a false economy as I would be splicing the sensors to the old connector

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share




×
×
  • Create New...