The two codes and my Check Engine light came on. I took it into a shop and they told me it was the catalytic convertor so they replaced it. I'm in the middle of the 50 mile 'driving cycle' before retesting and the Engine light came back on! What else can be wrong and how can I get the car to pass Emissions?!?
2007-07-31 12:55:31 · 3 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
P0133 is a slow responding 02 sensor. Replace it with a new one.
P0422 is telling you the catalytic Conv. is below its operating threshold. Maybe caused by the bad 02 sensor.
2007-07-31 13:06:11 · answer #1 · answered by R1volta 6 · 0⤊ 1⤋
97 Hyundai Elantra
2016-10-16 22:05:13 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Gigi....
the Hyundai Elantra's of this vintage have highly sensitive computers... I will try to help as best I can...
if they replaced the cat they should have also replaced the oxygen sensors also on this model there are 2 of them...
because if the catalytic convertor was bad enought to be replaced its general proceedure to replace the 02 sensors (oxygen) as well...
that stated I can tell you recently I had a first hand experience with how sensitive and special the Hyundai Eleantras Computer emissions system is first hand...
as an auto repair technician...
I was brough a 98 Elantra with 5 codes in it P0301 P0302, P0303, P0304, & P0300....
P0300 Random engine misfire
P0301 Misfire on #1 cylinder
P0302 Misfire on #2
P0303 Misfire on #3
P0304 Misfire on #4
engine was fuel fouling all plugs...
first thing Mitchell Manual said was test octane of fuel ...
what the hell I do not have a octane tester... I do not know any technician who does... I know the gasoline manufacturers must have them but I'll bet they're expensive...
concern was determining if fuel was above 87 octane or not!! running 87 or under octane is non sufficient to make these run right...
so I decided to get a bottle of best octane booster (sensor safe) Outlaw brand name and put it in tank...
within 150 feet the check engine light went out and misfire went away...
but diagnostic cost, and drving time to diagnosis and fix, compression test etc made the bill $291.96
just to tell customer stop putting the lowest grade fuel in this car run 89 and better octane only.... it not only gets better mileage but will not ruin the car...
first I would put 1 bottle of Outlaw brand sensor safe octane boost in tank with gas minimum specified on bottle...
then have shop test both oxygen sensors and or replace them then clear codes again...if the P0420 was present and returns the ECM Electronic Control Module aka Computer is bad...
below is what the mitchell said about codes you have/may have
your codes...
P0133= Front H02S Circuit Slow Response....this could be in part from it not being replaced when the cat was... it may be packed with carbon...
P0422??? mitchell doesn't show this for 97 Elantra...
but it does have that code for the Hyundai Accent model for 97 ...
Have the computer checked some idiot may have substituted a accent computer for the elantra one... this can cause real headaches for techs fixing these cars right...
P0420 = Catalyst Efficiency Below Threshold...recheck for this code with scan tool... if code P0420 is not present problem is intermittent follow no codes article proceedure if code P0420 present
check for exhaust leaks before and after the cat... repair theem as necessary if leaks are not found check rear H02S replace if bad... then clear codes if code resets replace ECM (The computer)
P0442= Evap Purge Control System ... rescan with scan tool for presence of P0442 code ... not present got to no codes article for repair proceedure
if present do following...
Check purge controll hoses check valve for sticking open or closed check fuel tank pressure sensor for blockage repair/replace as necessary
Walt
2007-07-31 14:43:18 · answer #3 · answered by Ronk W 4 · 0⤊ 0⤋