Hyundai

[sira]

Dear Friends

One my friend purchased Hyundai Accent 2002 last week. how ever the fuel consumption seems low also i can see the very dark silencer . changed the Air cleaner and Plugs too.

One thing i noticed was, the O2 sensor connect has broken. the sensor side plug seem melted and it is now totally disconnect from the ECU side connector. I'm planing to join them but i cannot figure out the wiring diagrame. How to find the correct wires . this got 4 wire O2 sensor.

Please help

Sira

[Rumesh88]

You should be getting a CEL indication and the car must b running on limp home mode if the sensor is disconnected? Are the colors like two grey wires, one white and one black on the sensor side? Two grey wires get 12V for the heater built into the sensor. Black is the ECU ground and white is for the sensor output. These Hyundai connectors become a real PITA as they age. They become so brittle even with the slightest mechanical stress they break into pieces.

[sira]

Thanks Ramesh

Not CEL indication , I think some one has bypass the light with other light. still we did not check the meter board. what i noticed was the fuel mixture looks very rich, plugs are black and lot of carbon dust on the silencer.

The sensor side

2 white , black and gray, - is black is sensor output ?

ECU side

2 blacks and i think one is gray or white.

https://www.google.lk/imgres?imgurl=http://i.stack.imgur.com/6EWo7.jpg&imgrefurl=http://mechanics.stackexchange.com/questions/15387/do-i-have-to-rely-on-wire-color-to-correctly-wire-up-an-o2-sensor&h=99&w=605&tbnid=2ruz_Ea0BG0qnM:&docid=aeVm6EJ9xcyJvM&ei=ClmvVpGBKYuYuQT_7LqQDw&tbm=isch&ved=0ahUKEwiRrqzD0dbKAhULTI4KHX-2DvIQMwg8KBowGg

this looks similar

http://www.ebay.com/itm/New-Replacement-O2-Oxygen-Sensor-for-Hyundai-Accent-Elantra-Tiburon-Kia-Sportage-/181947794745?hash=item2a5cef0539:g:LTQAAOSwgyxWXUST&vxp=mtr

How ever the sensor side connector had tampered. cannot connect it. messed up. so i'm just looking to buy a connection ad swap them . another thing is those wires are aluminium (sensor side) and may not be solder. if some one give me the exact pin diagram it will be much help

thank you

Edited February 1, 2016 by sira

[Rumesh88]

This is the second case of a Hyundai vehicle I came across with CEL indication bypassed. Seems to be a common makabass remedy . This is what they usually do to hide a man-made fault after accidentally damaging something inside the engine bay.

BTW you should have a downstream O2 sensor (after catalytic converter) with the same connection. On the sensor side two whites are for the heater. These two should be connected to the Light Grey and one of the Blacks on ECU side. (On the sensor side heater connection -two whites - should read about 5 - 6 Ohms when cold). Of the two Blacks on ECU side one goes to the ECU and other goes to the engine bay common ground. It is the one that goes to common ground that should be connected to the heater. If you check continuity with a meter, both these connections should show continuity to the ground but if you disconnect the ECU the grounding can be disconnected and you can isolate the one that goes to the ECU. The remaining connection on the ECU side should be Dark Grey and is for the sensor signal. Now to identify the sensor signal on sensor side run the engine with the heater line (two Whites) connected and measure the signal with a multimeter on 2V range. The wire that shows a positive reading is the sensor signal wire. Hope I did not make it too complected.

I have the diagram but the wire color code is not very clear in the PDF file. PM me your email if you want it.

[sira]

_Rumesh

_{yes perfect !!}

_{what can cause due to no O2 sensor? will the engine burn rich petrol. plugs are so dark. any way , where did you got repair your one?}

_sira

Edited February 2, 2016 by sira

[The Stig]

Can you rev the car higher than 3000rpm, if you can't that means the car maybe in limp mode.

Are the connecter wires to the O2 sensor connect together (our makabases do this to bypass the O2 sensor reading and prevent a check engine light)

[The Stig]

_Rumesh

_{yes perfect !!}

_{what can cause due to no O2 sensor? will the engine burn rich petrol. plugs are so dark. any way , where did you got repair your one?}

_sira

O2 sensor determines the air/fuel ratio of the engine and yes an incorrect reading will lead to the engine running rich

[Rumesh88]

_Rumesh

_{yes perfect !!}

_{what can cause due to no O2 sensor? will the engine burn rich petrol. plugs are so dark. any way , where did you got repair your one?}

_sira

You got the answer to your question from The Stig above.

The vehicle I referred to above is a Getz belonging to one of my relations, not mine. As for the repairs it was done in a DIY manner with a cheap OBDII scanner from ebay. read the last post on http://forum.autolanka.com/topic/15943-problem-huyndai-getz/?hl=getz

[sira]

Can you rev the car higher than 3000rpm, if you can't that means the car maybe in limp mode.

Are the connecter wires to the O2 sensor connect together (our makabases do this to bypass the O2 sensor reading and prevent a check engine light)

Yes, i can , i drove this car at 130 Kmph at highway. so with od off then it reached 4-5k. did not see any issue.

No cannot connect O2 connector as it broken. i'm trying to buy aftermarket 4 pin connector and swap both ends

[sira]

Guys

Finally i manged to connect the O₂ Sensor side broken connector to Harness connector. Thank you very mush Rumesh the diagram is very useful. the sensor side pins were ok so i just plug each pins to harness side connector and cover the open connector with abro gasket sealant to prevent water go inside.

I removed the meter board and noticed that some of F**king ass had cut the MIL light wire and connect to charging light. so i restored them. so after the O2 connector restored , MIL was on .then i removed the battery wire and leave it for a 10 min.then connect the battery wire. MIL was still on . then leave engine on for a 10 min and MIL was gone.

how ever my friend said some time he sees the light and some time it will go off. do not know the issue as i do not have OBD scannoer. i have ordered one from Ebay - bluetoth one which can connect o anroid phone. so will see.

is there any way to read mil code ?

sira

[Davy]

Good job!

is there any way to read mil code ?

sira

If you're using a cheap Bluetooth adaptor, this is the way to go:
http://forum.autolanka.com/topic/14674-diy-scan-your-own-car/

[Rumesh88]

Good job! BTW did you check (or at least sure of) the condition of the timing belt? Last time when I came across a Hyundai that had undergone a similar fate it was due to a timing belt which had slipped by two teeth http://forum.autolanka.com/topic/15943-problem-huyndai-getz/?hl=getz. The connectors are a real problem with these cars. In fact I am looking for the part number of a complete harness these days trying to get it down from somewhere.

[sira]

Hi Rumesh

My friend asked me to change the T-belt too. I'm pretty sure i can do that. i have seen when upul change my EK3 T-belt. also whet thro' with the manual after that and it is not a big deal.

How to lose the crank shaft pully ? since this auto car i believe with the gear position the engine may not run. then no way to lock the engine to lose the nut.

according to the manual , i will follow the procedure of changing the t-bet

sira

[sira]

Hi My friends

My Hyundai friend had some sort of issue recently. 

It start burn engine oils and one of mechanic has replaced piston rings. it has now fixed. now he complain about heavy black smoke on exhaust. Then ee met one chap in athurugiriya. he seems used to work at Hyndai.  

he scan the ECU and only show the o2 sensor issue. then he exchanged the Air floor sensor with another one and checked. no luck. then we checked the spark plugs. Bloddy hell. all of them were surrounded by full of carbons. then cleaned it.  I believe  think this may happen due to engine oil burn issue but that baas hand not clecnned the plugs. 

when we test it the black smoke reduced. but he said the Air floor sensor need to be replaced. and it was 14K. my friend did not had such money that time and we fixed the old air floor sensor back. after 3, 4 hours time he called and said , the black smoke has gone now and  if i accelerate high then small amount come up. so i sad lets see for a few days time as you had engine oil issue and rich fuel consumption  issue some more carbon still exists in the exhaust . so will wait and see. 

Another issue that hundai chap identified was that O2 sensor. The connector has removed during the piston rings change time and now it again giving the error code and cannot clear. he said replace that sensor because if its incorrect wiring  the O2 sensor and ECU can damage too. Then you need to replace the ECU (22k) or repair (8K) 

What do you think of that statement. will there be high current comes to O2 sensor Heater? is it coming via ECU?

please let me have your valuable comments

Thank you 

Sira

 

[Rumesh88]

Just like spark plugs the O2 sensor also must be now covered with carbon deposits. Before you decide to replace the O2 sensor check its heating element for continuity. If the heating element is bad you have to go for a replacement. Otherwise remove it (mind you it is not easy) and heat the element with a gas torch or a blow lamp until it is red hot. Do this a couple of times until deposits clear. If the deposits are still hard to remove, dip the element in water after heating a couple of times. Keep in mind that this is a brute force method and you may end up totally destroying the sensor but it is a chance worth taking. You can do a bench test to confirm proper working of the sensor by connecting the sensor element connection (if you can identify two heat element wires, the remaining two wires goes to the sensor element) to a volt meter set in 2V range. Heat the element red hot and observe the reading. As you go on heating the reading should go up to around 900mV. Also when you take the heat source off the reading should comedown towards zero in a couple of seconds time. Otherwise the element is bad. The four wires to O2 sensor comes from the ECU and you have around 1.5 to 2 Ampere current flow to the heating element of the sensor. However, wrong wiring is unlikely to damage ECU unless you short circuit the two wires going to the heater. You can test if the power is available to heating element by connecting a 12V filament lamp (a signal bulb is good enough but make sure you do not short circuit the wires) and turning ignition on.

Edited January 30, 2017 by Rumesh88

[sira]

Thanks Rumesh

The Hyundai man said if the 02 issue keep cumming after installing the new sensor, then ECU may have damage due to short circuit,

we will be vising another place today at Palawatta area and will see what his views too. 

sira

[sira]

On 1/31/2017 at 10:58 AM, sira said:

Thanks Rumesh

The Hyundai man said if the 02 issue keep cumming after installing the new sensor, then ECU may have damage due to short circuit,

we will be vising another place today at Palawatta area and will see what his views too. 

sira

The new Hundai man has replaced the O2 sensor and reset by removing the battery terminals. the error has gone but after 2, 3 hours time when engine off and one it appear again.Do you think ECU has damaged?

sira

[Rumesh88]

Before you decide on the ECU check if the power is available for O2 sensor's heater. If you do not get power then you will have to either repair or replace the ECU. Of course there are chances for the other two wires -ie input to the ECU to fail but a rare possibility. Now that you have the wiring diagram check the wiring from ECU to the sensor as well.

Edited February 2, 2017 by Rumesh88

[Nalin Gotabaya]

Hi guys, I have Hyundai assent 2000 auto car. I am planing to change engine oil. Last time i used caltex 15-20.  I have done more than 200000km. Therefore some peoples said it is bet to use 20-40 something ....something more thicker.. I am in confused..  someone please advise me....

[Rumesh88]

Caltex 15-20 and 20-40???? Never heard of such thing. I thought they have 0W-20, 5W-30, 10W30 and 15W-40. Could you please confirm the exact rating of the oil you used last time? If the mileage is 200,000km and no overhaul done (confirm this too) before, then go for 15W-40.