P0422 Diagnostic Code
sagacity
10-23-2005, 05:50 PM
I just bought a 2000 Hyundai Elantra and I am continuously having problems with it. The check engine light comes on and it reads the P0422 code, which is main catalyst efficiency below threshold. In addition to this code, when I am stopped, my car idles high at times, the needle fluctuates between 2000 rpm and 1500 rpm. and I am getting horrible gas mileage. 85% of my driving is freeway driving and I'm getting about 24 mpg, it seems to get worse everytime I drive. Could all these problems be related? I don't know if replacing the oxygen sensors would do the trick or if it's really the catalyst converter. If anybody can help me figure out what's wrong, I would greatly appreciate it. Thanks!
beancounter
10-23-2005, 07:50 PM
I can't help you on the code, but I have a suggestion about the low MPG. Mine was getting kinda low, maybe 23-24 on the highway. This week I drained ALL my fluids and added new fluid to everything, did an oil change, put in new antifreeze about 2 weeks ago, and this weekend I drove 500 miles and averaged 31MPG, which included a 45 minute traffic jam in Raleigh and some slow moving downtown traffic.
My car did idle high a few years ago, then it just decided to stall instead. New set of spark plugs and connectors did the trick on that one.
BTW, I'm also driving a 2000 elantra
My car did idle high a few years ago, then it just decided to stall instead. New set of spark plugs and connectors did the trick on that one.
BTW, I'm also driving a 2000 elantra
luvsvettes
11-07-2005, 03:20 PM
I just bought a 2000 Hyundai Elantra and I am continuously having problems with it. The check engine light comes on and it reads the P0422 code, which is main catalyst efficiency below threshold. In addition to this code, when I am stopped, my car idles high at times, the needle fluctuates between 2000 rpm and 1500 rpm. and I am getting horrible gas mileage. 85% of my driving is freeway driving and I'm getting about 24 mpg, it seems to get worse everytime I drive. Could all these problems be related? I don't know if replacing the oxygen sensors would do the trick or if it's really the catalyst converter. If anybody can help me figure out what's wrong, I would greatly appreciate it. Thanks!
is this the only code that ou are getting? checked for vacuum leaks?
is this the only code that ou are getting? checked for vacuum leaks?
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