Engine Management Light

[Burning Feet Man]

Hello all,

I was driving my celica the other day and the engine management light came on. There was no problem evident, the car drives perfectly fine, the levels of fluids are all acceptable. However, i need to find out how to reset the light to determine if it is indeed a 'hard' fault or just a glitch. Is there any way to reset it other than Visiting Mr T. ? Would the light go off if the fault was rectified, or does it still need to be reset by Toyota? Finally can you give me an idea of things to check before i take it in, which systems are connected to the engine management system and where might i find the indicating components? As there is no physical symptoms of a problem im more expecting it to be an indicating problem, so a loose connection somewhere is my first guess. Thanks to all, in advance, for your help

Mikey

[jerry phipps]

Hello mate

This could be a number of problems. You could try removing the ecu fuse for about 10 minute. That should reset the engine light. Or if you dont want to do that you could also remove the minus terminal from the Battery also that should reset it too. Causes for engine light coming on. I'm guessing it could be your mass air sensor for the air intake. If these become dirty or have had a knock it will make the light come on. These are very temperamental and will probably need a good clean.

Failing that have you had a performance exhaust fitted to your car? Or have you decated it? Or it could be a fault with the cat? Just a few pointers for you mate ;)

jerry!!

[bgorman]

Hello all,

I was driving my celica the other day and the engine management light came on. There was no problem evident, the car drives perfectly fine, the levels of fluids are all acceptable. However, i need to find out how to reset the light to determine if it is indeed a 'hard' fault or just a glitch. Is there any way to reset it other than Visiting Mr T. ? Would the light go off if the fault was rectified, or does it still need to be reset by Toyota? Finally can you give me an idea of things to check before i take it in, which systems are connected to the engine management system and where might i find the indicating components? As there is no physical symptoms of a problem im more expecting it to be an indicating problem, so a loose connection somewhere is my first guess. Thanks to all, in advance, for your help

Mikey

To clear the light just disconnect the Battery -ve for 5mins.

If it comes back on again it may just be that the MAF sensor needs a clean,(given that the car runs normally).

[Burning Feet Man]

Thats great, thank you for your help guys, in the morning (more like lunchtime :) ) i will try removing the -ve terminal and see if it clears it. If not i will have a go at cleaning the MAF sensor. could you give me a hint as to the best way to clean it? is it wire brush stuff or more like a soft cloth? Thanks again for your help.

Oh sorry Jerry, the car is totally standard, and i really hope its not a problem with the cat :(

[jerry phipps]

You want to be really careful cleaning this. If you knock it or even place it back un even it could cause problems. Some peeps use a air blower on it just a few blasts of air over the sensors. Perhaps use a foot pump with the nozzle on it and gently blow over the sensors hopefully that might remove any muck and dirt or a cotton bud?

jerry!!

[Burning Feet Man]

Oh, i hate the delicate stuff hehe. so do i remove the pipe at one side and just give it a bit of a clean, or remove the whole thing? I'll be very gentle with it as i dont want to introduce yet another problem to my car. failing that, what does a MAF sensor cost as if cleaning it works, even for a bit, i may consider replacing it with a new one. Thanks again, i love you guys :)

[Burning Feet Man]

Ok i just got back from playing with me motor, i removed the -ve and left it whilst i fiddled with every plug i could to ensure they were seated correctly, i did the same with all fuses. I then had a play with the MAF sensor ( its got basically an elongate loop of wire yeah? i just gave it a blowing, it didnt appear dirty, although it was not screwed down tight, it had some play in it. reconnected the -ve and the fault has gone. Brill :)

Now, i must ask, does this indicate that the problem is gone, or the ECU is now 'mapped' to accept this fault? Sorry but i've a limited knowledge of cars so thats probly a silly question.

Thanks again :)

[fiz-vvti]

thank you to all who have posted on this as i have had a very similar problem and this makes alot more sense than what the garage told me.

thanks burning feet man and i hope ur problem is solved as well

[Burning Feet Man]

Ok the warning light has stayed out so far, but tonight i have a 200 mile trip to test it lol. Can i just re-ask a question i asked earlier, have i deleted the fault and it hasnt returned, or have i just told let the ecu learn that how it is is how its meant to be? I also like to ask that, since resetting the ECU my car seems somewhat sluggish under heavy accelaration, is this just the ecu remapping itself and learning my driving from scratch? Im a little concerned as this wasnt present before i reset it. Thanks for your replies guys (and gals? )

[LeoM]

I have the same issue, however the check engine light goes off as suddenly as it goes on, in an absolutely random way.

I can't wait and check the procedure from this thread on my car :D :D I'll do it Sunday maybe.

Thanks a lot guys!

Leo

[fazzer]

Ok the warning light has stayed out so far, but tonight i have a 200 mile trip to test it lol. Can i just re-ask a question i asked earlier, have i deleted the fault and it hasnt returned, or have i just told let the ecu learn that how it is is how its meant to be? I also like to ask that, since resetting the ECU my car seems somewhat sluggish under heavy accelaration, is this just the ecu remapping itself and learning my driving from scratch? Im a little concerned as this wasnt present before i reset it. Thanks for your replies guys (and gals? )

if you reset the light and cured the fault the light will stay out but if you have just reset the light and the fault is still there it will come back on in time(depends what the fault is)

[Arash Azimullah Sohrabie]

Hey Hey,

Engine management could indicate several problems as probably everyone already mentioned.

This is very common with toyotas with cold air filter installed.

one is air mass sensor which has to be cleaned (worst case scenario) replaced.

ADVICE, buy Denso the original one and no replicas!!!

Another one is the Labda probe on your exhaust system.

Despite all the warnings, a broken labda probe is not severe since it is mostly made for environmental cause.

This on the long term could affect your emmision!

replacing it would cost you around 130 euros (ordering it from germany)

if the engine management light is winking then you have a serious problem.

The engine will go on emergency mode and yo will only have 30 bhp!

You might have to replace your whole filter installation and sensor, followed by new spark plugs (not so expensive)

I would reset it and see what happens. Should this happen again, i'd suggest going to a garage!!

good luck