HELP!!! PLEASE!!!

[Anonymous]

Hi there, i have an X reg 2000 Roadster.

On Saturday i noticed that the engine management light was on, so i took it to my local Toyota Dealer, after doing their checks they have said that both the 'Air sensors' that help mix the fuel have failed, and they want to charge me £137+VAT per sensor, with a total price of £637, that includes their diagnosis, parts and fitting. Do you think that is too high? Also i have had a word with a friend of mine who knows alot about cars and he's said that he's never heard of both sensors failing at the same time? Has anyone else heard of them both going at the same time?

Any feed back would be most greatful!

Many thanks!!

Graham

[uktotty]

MAF (Mass Airflow Sensors) have a retail of around that price, however we have an affiliate on here (Cheap Toyota Parts) who may get you a better price, installation costs nothing as its 2 screws.
As far as I am aware there is only ONE of these in the MR2
You may be referring to O2 Sensors (oxygen sensors) which there are 3 of.
We need to know the CODE for the error as this is probably a P0141 which can be fixed for around 40 pence with a resistor.
Let us know WHERE you are, so that we can get the code read and give you some proper feedback.

[Anonymous]

Thank you for the reply, im in Bromsgrove, the car is at the local Westlands Toyota Garage, i can give them a ring and find out the error code if thats of any help?
The guy definatly said that "one of the air sensors had failed and as a result had taken the other one with it, so you are going to need two new sensors"
They said that it would take about an hour to fit the parts, which they are charging at £75+VAT, so if it is just 2 screws then they are definatly screwing me! (pardon the pun) Do you need any more information?

[SimonC_Here]

Dirty MAF is a possibility.
2 o2 sensor failing at the same time seems a little strange.
Get the codes if you can and if you're a little mechanically minded you may be able to save loads.

Just seeing your post. Changing the MAF is a 2 screw 5 minute job.
Changing the sensors is a 2 minute each job as long as you are careful when putting the new ones back in.

As to how 1 failing can cause the other to fail I'm at a loss. They don't interact with each other and are just sensors!

[Anonymous]

I've had dealings with this Toyota franchise before and they are not the most helpful in the slightest.

[StuM]

They said that it would take about an hour to fit the parts

If they are talking about the MAF, it could probably be done in under a minute.  As they are talking multiple items, they will almost certainly be referring to oxygen sensors.  There are two of these in the exhaust mainfold (and a further one downstream from the CAT) and failure is not uncommon.  [edit]Agree with Simon, can't see one causing the other to fail[/edit]

You do have other options than Toyota even if they do need replacing - replacing with non-original parts has been done by others on here.  This route might need a little bit of fiddling with the wiring, but nothing too hard.

The O2 sensors are screwed into the manifold and both could be replaced in under 5 mins if like for like (as it would be at Toyota).

Ask the garage to give you the error code...

Cheers,

[Anonymous]

Right, after they finally answered the phone, ive got the Error codes that they've identified, they are:

P0171
P0174

Does anyone know what these codes are and what they relate to?

[Anonymous]

I was having a look through the search and notice that a lot of old links on obd2 codes are now not working.  From memory the  codes do not relate to the o2 sensors but a leak in the vacuum system or exhaust

Type in your first p code number into the search at the top right and the item has been discussed  s:D s:D

[SimonC_Here]

# P0171 System too Lean (Bank 1)
# P0174 System too Lean (Bank 2)

[Anonymous]

Had a quick scan through the reasons for it and it appears the initial cause may be a faulty MAF.  Its a ten minute job to take it out, clean with carb cleaner and refit.  Its worth a try first and a hell of a lot cheaper for you to do that the £600 quid  s:scared: :scared: s:scared:

[Anonymous]

So is there just the one MAF? If so why did the garage say both of them? Would a faulty MAF cause both the sensors to fail? Or are the sensors nothing to do with that?
Also we've been looking around on the net and we've found an artical saying that there is only the one O2 sensor or Lamda sensor in a single exhaust Mr2 and that it is only on twin exhaust that there are two sensors? Does anyone know about that?

If we take out the MAF clean it and replace it, will this then get rid of the Engine Management light? (maybe a bit of silly question, but as i said above i know diddly squat about cars unfortunatly)

[SimonC_Here]

So is there just the one MAF?

Yes. it monitors the air flow into the engine

If so why did the garage say both of them?

They are talking about the O2 sensors

Would a faulty MAF cause both the sensors to fail? Or are the sensors nothing to do with that?

Not fail but may make they read as too lean or too rich.

Also we've been looking around on the net and we've found an artical saying that there is only the one O2 sensor or Lamda sensor in a single exhaust Mr2 and that it is only on twin exhaust that there are two sensors? Does anyone know about that?

Show us where so we can point and laugh!  s:) s:)
There are 3 in most UK cars (two in the manifold next to the engine, one in the exhaust after the main cat)
Some people have removed that last one and replaced it with a resistor if it has failed.

If we take out the MAF clean it and replace it, will this then get rid of the Engine Management light? (maybe a bit of silly question, but as i said above i know diddly squat about cars unfortunatly)

You have to reset the light by discaonnecting the battery for 20 odd minutes. Go for another 3 long ish drives and see if comes back on. 3 drives as some codes have to be triggered 3 times before they show.

[Anonymous]

From what i am aware and im not an expert

1.  There are 3 sensors on the mr2 irrespective of single or twin exhaust--2 in the manifold and 1 after  the main cat--I think the only difference is jap spec cars where there are only 2.

2.  I would suggest you clean the maf first--once you do this disconnect the negative terminal from the battery for approx 20 mins this will reset the ecu and extinguish the cel

there are loads of references on here to maf, your codes etc and if you do a bit of research on here you will save yourself money.  Members are buying sensors for about £60.00 each and if you are near another member i'm sure that they would give you assistance

[chalced]

If you fancy a 20 min. trip down the road (Coventry) on Friday I can take out and clean the MAF sensor for you and reset the ECU (disconnect battery).
All you will have to do is reset your radio channels afterwards.....and all for the price of a pint down the local.....

Mel.

[wbarrwebster]

If you fancy a 20 min. trip down the road (Coventry) on Friday I can take out and clean the MAF sensor for you and reset the ECU (disconnect battery).
All you will have to do is reset your radio channels afterwards.....and all for the price of a pint down the local.....

Mel.

That's a deal and a half!!!! lol

B

[Anonymous]

That would be great thank you mel!  s:D s:D  If you email me a meeting spot, i.e your local pub? Then we will meet you there on friday, what time would be convenient for you?

Also its fine to drive on it isnt it? Its not goin to cause any damage?

My dad reckons that they have just said that both sensors need replacing as they cant work out which one has actually failed, is there a way of checking to see which one has actually failed (should the cleaning of MAF sensor not solve the problem)
Or is it just going to be a case of buy one to start off with, replace the one, reset the ECU and if it comes back on, then swap them around (replace the old one with the one i took out) and reset the ECU again?

[ekimq]

Provided your car hasn't started drinking oil you should be okay to drive.

Take a look at the thread above on OBD II readers - you should find someone nearby who can read your codes to see if things get better or worse as you try and eliminate possibilities.

You'll notice that regulars tend to use abbreviations without necessarily explaining what they mean. If you're at all unsure and a search doesn't explain, feel free to ask.

[Anonymous]

Hi soup-a-man, if you do get stuck I'm only in Redditch. I don't have a code reader (yet) though. If those are the codes, I would agree with the MAF sensor. Is that Toyota (westlands) the one in Shirley or the one near Stoke Pound on the A38?

Cheers

Chris

[Anonymous]

Thats great news about the car being ok to drive, i will keep an eye on the oil!

Its just a thought, might be complete rubbish buttt, when i bought the car, as i got the car home, the engine blew up, to be exact it started buring oil on the way back home (according to toyota) and so i had to to have a new cyclinder block, (total cost was £2.5k) toyota at the time said, that is was a common fault with the 1.8 vvti, that it used oil much quicker than it should, that was last year and i have been checking every few weeks to make sure that its not using any oil and so far it hasnt used any, so my question is, could the damage done by the engine blowing up of caused the problem in the MAF or could an underlying problem of been the cause of them both? Or am i just really really really really unlucky?

Its the Westlands Toyota in Stoke Pound on the A38, at the back of the Bromsgrove Morrisons. Thank you for your offer Chris, all help is always welcome!  s:) s:)

[chalced]

Shouldnt use excessive oil unless theres a problem. Mine uses hardly any oil for 6000 plus miles.
Have you got rid of the dreaded pre-cats??

Mel.

[Anonymous]

It does sound like the MAF to me. You should have pretty recent o2 sensors (commonly referred to as Lambda sensors) if you have a new engine as the old one's would have been toast.

Chris

[SimonC_Here]

Thats great news about the car being ok to drive, i will keep an eye on the oil!

Its just a thought, might be complete rubbish buttt, when i bought the car, as i got the car home, the engine blew up, to be exact it started buring oil on the way back home (according to toyota) and so i had to to have a new cyclinder block, (total cost was £2.5k) toyota at the time said, that is was a common fault with the 1.8 vvti, that it used oil much quicker than it should, that was last year and i have been checking every few weeks to make sure that its not using any oil and so far it hasnt used any, so my question is, could the damage done by the engine blowing up of caused the problem in the MAF or could an underlying problem of been the cause of them both? Or am i just really really really really unlucky?

Its the Westlands Toyota in Stoke Pound on the A38, at the back of the Bromsgrove Morrisons. Thank you for your offer Chris, all help is always welcome!  s:) s:)

Looks like the car had the dreaded pre-cat failure/oval bore problem and it was fixed. So you should  be fine. The excess oil may have hastened the demise of the O2 sensors but thay may have been changed at the time and you won't know until the MAF is cleaned and you've ruled that out.

MAF cleaning:
 m http://www.spydermagazine.com/2002/Marc ... _clean.htm m

O2 sensor replacing:
 l viewtopic.php?f=47&t=21462 l

[Wabbitkilla]

Do you know if the cat and pre-cats were replaced at the same time?

But for now, I'd just clean the maf and reset the ecu and see how it goes - nothing to be proved until you do that and ... it's a lot cheaper than what that garage were asking eh?   s:wink: :wink: s:wink:   It is very unlikely that both O2 sensors go at the same time, that's rare indeed.

[Anonymous]

Yep looks like the car did have the pre-cat failure/oval bore problem, i've just been reading about it in another thread and it sounds almost exactly like what happened! (sudden rapid buring of oil and loss of power!) Apparantly, so the garage said at the time, toyota had recognized there was a problem and so had extended the warranty covering it to 7years, however mine missed out by a matter of weeks and so they wouldnt cover it under the warranty, so was of no use to me, but might be of some use to other owners?

Im not sure/cant remember off the top of my head what was replaced in the engine rebuild last year, but i will find out later and see what was replaced!

[spit]

If you have a multimeter handy, then its OK to unplug the manifold O2 sensors one at a time while the car is idling warm and measure the voltage across the blue and white wires from the sensor. If the sensors are working OK, the voltage should be dancing around nicely in the 0.4 to 0.8 ish volts region. If they're reading low or sluggish then they may well be pooped.

But, like others, I'm inclined to believe your problem is down to a slow dirty MAF which is leading to a falsely low airflow reading which is leading to false under-fuelling which is leading to the O2s seeing low fuelling which is causing the ECU to trim to its limit before it throws a "too lean" CEL.*phew*

That, or a hose split or pop-off at the intake letting unmetered air in, which could have the same consequence.

Start simple before parting with silly money.