Emissions Problem
04-27-2008, 07:39 PM
#1
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Vehicle: Hyundai Tiburon FX
I have a few problems. Tried every wiring possibility on the extended O2 sensors even with the correct wiring diagram. Both sensors are brand new OEM front and back. My wiring is good, soldered...etc. Catalytic converter is passing and oxygen heater is passing. I failed emissions again.
The computer keeps giving me bank 1 sensor 1 & 2 codes.
P0137 - Oxygen sensor circuit low voltage.
P0133 - Oxygen sensor circuit slow response.
P0501 - Vehicle Speed Sensor Malfunction (my abs light is on)
#1) Found that online. Could it be my MAF that's causing this?
#2) I replaced the speed sensor but the speedometer still doesn't work.
The computer keeps giving me bank 1 sensor 1 & 2 codes.
P0137 - Oxygen sensor circuit low voltage.
P0133 - Oxygen sensor circuit slow response.
P0501 - Vehicle Speed Sensor Malfunction (my abs light is on)
QUOTE
You also need to check **Very important** you Mass air flow sensor. Actually if you get a code that reads both oxygen sensor Bank 1 and Bank 2 you need to suspect your Mas Air flow sensor or you Fuel pressure regulator, also while you are doing this look for air leaks. Not your o2 sensors.
#1) Found that online. Could it be my MAF that's causing this?
#2) I replaced the speed sensor but the speedometer still doesn't work.
04-30-2008, 07:47 PM
#2
Moderator
Is your MAF sensor reading 3GPM at idle?
You can buy a new sensor at advanced for a 1999 Kia Sportage. It is the same part number. It is branded with the Kia logo instead of the Hyundai logo. It's the same part, just instead of no availability and 2 weeks backorder, they have them in stock for $100 cheaper. They're like $70 and come with a lifetime warranty. I'd buy one, try it, then if it dosn't fix the problem, return it and claim you never installed it.
You've been going through this problem for entirely too long and gone through / spent entirely too much already. I'd say a bit of underhanded troubleshooting is in order.
Slow response = dead sensors usually. It's possible they are both dead.
that 501 is probly from your auto-> manual swap. Check the wiring at the speed sensor next to the shifter linkage.
You can buy a new sensor at advanced for a 1999 Kia Sportage. It is the same part number. It is branded with the Kia logo instead of the Hyundai logo. It's the same part, just instead of no availability and 2 weeks backorder, they have them in stock for $100 cheaper. They're like $70 and come with a lifetime warranty. I'd buy one, try it, then if it dosn't fix the problem, return it and claim you never installed it.
You've been going through this problem for entirely too long and gone through / spent entirely too much already. I'd say a bit of underhanded troubleshooting is in order.
Slow response = dead sensors usually. It's possible they are both dead.
that 501 is probly from your auto-> manual swap. Check the wiring at the speed sensor next to the shifter linkage.
05-05-2008, 06:33 PM
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Vehicle: Hyundai Tiburon FX
P0501 repaired. Turns out one of the wires on the connector was rusted out and broke off. Reason for it? Total anomaly, seperate from the rest of the problems. That's fixed now!
Thanks for your help DTN. Me and daniel_depetro are having the same exact problems with the same O2 codes. Both he and I have tried replacing all sensors with OEM new ones and we know our wiring is 100% correct. We both have aftermarket exhausts with aftermarket catalytic convertors. Even if the cat was the problem, why would sensor 1 give a low voltage code? Not sure about his, but my catalytic convertor is after the flex pipe and it might not warm up quick. Our sensors are heated and the DTC heater tests pass and low voltage codes come up right at the same time as that.
If it's not electrical, I think these are possible causes:
1) Airflow under car cools the temp of the sensors enough to give below average readings. Computer thinks it's not heating the sensors quick enough.
2) Backpressure (my mechanic friend was telling me sensors will trip in hondas if the backpressure is off by a hair.
3) Not enough exhaust stream due to larger piping.
???4) Could it be we have to unplug the neg- battery terminal to drain the entire circuitboards of their memory?
The MAF is giving a good reading too, 3. something. When daniel said he was at a loss, i too have no more shadows to keep myself cool.
Found this:
It could be the PCV that's causing the problem... I'm not sure...
Thanks for your help DTN. Me and daniel_depetro are having the same exact problems with the same O2 codes. Both he and I have tried replacing all sensors with OEM new ones and we know our wiring is 100% correct. We both have aftermarket exhausts with aftermarket catalytic convertors. Even if the cat was the problem, why would sensor 1 give a low voltage code? Not sure about his, but my catalytic convertor is after the flex pipe and it might not warm up quick. Our sensors are heated and the DTC heater tests pass and low voltage codes come up right at the same time as that.
QUOTE
I checked and rechecked the way they were connected/wired. After everyone said 'you must have it wired incorrectly'. I checked the wires time after time after time. I actually removed the wiring and started completely over just to make sure there wasn't a broken wire somewhere. It didn't matter. I was using new a premium Bosch O2 sensors at first and had them exchanged out (on warranty) thinking maybe they were defective. No dice. Then I figured maybe the Bosch sensors just weren't reading something right or a value it was reading was just a fuzz off so I ordered factory Hyundai O2 sensors and of course nothing changed. Keep in mind I have two 2000 Tiburons so I just put the the new Bosch O2 sensors in my other Tibby.
-danielIf it's not electrical, I think these are possible causes:
1) Airflow under car cools the temp of the sensors enough to give below average readings. Computer thinks it's not heating the sensors quick enough.
2) Backpressure (my mechanic friend was telling me sensors will trip in hondas if the backpressure is off by a hair.
3) Not enough exhaust stream due to larger piping.
???4) Could it be we have to unplug the neg- battery terminal to drain the entire circuitboards of their memory?
The MAF is giving a good reading too, 3. something. When daniel said he was at a loss, i too have no more shadows to keep myself cool.
Found this:
QUOTE
-Vacuum hoses (splits/cracks)
-Check PCV for proper installation and condition (it should rattle, if you're brave, blow into the outlet (intake manifold side) and make sure it stops flow)
-Check the Mass Air Flow sensor (ie: no blockage in the screen)
-Check Fuel pressure
-Check Fuel filter (see above)
-Check PCV for proper installation and condition (it should rattle, if you're brave, blow into the outlet (intake manifold side) and make sure it stops flow)
-Check the Mass Air Flow sensor (ie: no blockage in the screen)
-Check Fuel pressure
-Check Fuel filter (see above)
It could be the PCV that's causing the problem... I'm not sure...
05-05-2008, 06:58 PM
#4
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Let the sensors warm up for about 5 minutes, then post a picture of the graphs of bank 1 sensor 1 and bank 1 sensor 2. That should give us a good answer.