Y reg Daewoo Matiz

1_step_closer

Hi

I am hoping someone is able to help my husband and I as neither of us are mechanically minded.

End of October last year, the management warning light came on. Took it to ATS who looked and said they couldnt see what was wrong so reset the cpu thingy.

Mid December it came on again - back to ATS who said it came up with an unknown error so I should go to a main dealer. They had a look and said the oxygen sensor thingy (in the exhaust) was loose so tightemed it up reset the cpu and away we go.

The light has just come on again (!!!!!) so back down to the main dealer who said that there were now 2 errors, something to do with the oxygen thing (which was still secure from when they tightened it) and that I needed a new cat converter. They also wanted £585 to do this so I said we would have to get back to them as we dont have that sort of money. The switch is reset again but not hopeful it will stay off. and to be honest I had probably only driven the car 10 times since December.

Now our questions are these:

1. reading on forums it looks like an EGR valve - what is that? and what does it do? and is it the same as the oxygen sensor?

2. why would I suddenly need a new cat when the car has just had and passed its mot? or would that error come up because of the first error?

3. How expensive and difficult is it to get and replace an EGR valve?

I have noticed that when the warning light comes on, it stalls quite readily and drinks petrol like its going out of fashion. :mad:

All/any help would be greatly appreciated!

Thank you

1 step x

Rossy.

EGR valve is used only on diesels

Is your's a diesel?

They are easy to take off and clean yourself. Google the car or look in a haynes manual to see the location of it.

Take it off and clean it with a wire brush to remove the built up carbon, use petrol or something similar that will break the carbon down.

New gasket and refit

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Thank you but mine is petrol......

hubert_cumberdale

egr valve is on petrol models too
the matiz is probably running vauxhall gear

it recirculates exhaust gases back through the engine to reduce emissions but if it gets stuck it can cause the car to stall or run rough. its just another thing to go wrong

as you said its stalling the EGR valve is probably most likely these are common failure on vectras and i imagine daewoo probably use the same one

the oxygen sensor is in the down pipe probably before the cat ( some cars have 1 before and 1 after) this basically looks at the oxygen in the exhaust gases and lets the cars brain know what to do with the fuel squirt more in or less. so these can result in high fuel consumption when faulty.

i would buy a new one from an auto factors and fit your self actually quite easy just a couple of bolts.

heres one on ebay its £192 but there are second hand ones as well

looks like you would have to undo a plug and 2 bolts

colino

Your car does have an egr valve (they can be on both petrols or diesels) but if you paid for a diagnostic, you really should have the codes or a description of them. Go to a local independent and have the car checked over, until then its just a guess, could be as simple as a slight exhaust leak.

Rossy.

I really never knew they fitted them to petrols too !!

learn something every day.

EGR's are a pain in the a$$.. Completely useless and cause all sorts of issue

oscarward

My understanding is that the oxygen sensor monitors exhaust emissions and adjusts engine /fuel settings to get better emissions.

If it fails then fuel can run rich, thus poor economy, and poisons the converter. Think they were also called a lambda (?) sensor.

The sensor is fairly cheap but cats aren't.

Try an independent garage, you may be able to get away with just having the sensor replaced.

hubert_cumberdale

someone has had this on here

https://forums.moneysavingexpert.com/discussion/1415895

Rossy.

oscarward wrote: »

My understanding is that the oxygen sensor monitors exhaust emissions and adjusts engine /fuel settings to get better emissions.

If it fails then fuel can run rich, thus poor economy, and poisons the converter. Think they were also called a lambda (?) sensor.

The sensor is fairly cheap but cats aren't.

Try an independent garage, you may be able to get away with just having the sensor replaced.

Lambda sensors can be up to £80 odd each on certain cars.

Don't see why a petrol would need an EGR valve.

Turbo diesels use them to recurculate the exhaust gases back into the inlet manifold to cool it under heavy boost

I've never had a petrol car with an EGR. What a strange set up

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Thank you for your help!

Casanova

Failure of either a lambda (oxygen) sensor or air inlet pressure sensor (goes by many names) would make the light come on, and cause overfuelling (which is what your car is doing if it stalls a lot and drinks petrol). Sensors are relativey cheap to replace, and the code from when you had the ECU read should point you to the culprit.

As mentioned above, overfuelling can kill the catalytic converter, which is expensive to replace. BUT don't be conned into getting that replaced until it fails an MOT on emissions - there are no ill effects from a faulty cat, and they are very commonly mis-sold.

It could be an EGR fault (they are fitted to both petrols and diesels) but this less likely I feel, given the other symptoms.

Best of luck getting to the root of the problem.