High CO & HC emissions
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High CO & HC emissions
I had my car inspected and the emissions tested today and it just barely passed (previous years had very low levels, nowhere near the limit). Today CO read at .99 (limit: 1.1) & HC read at 273 (limit: 275). RPM's were at 1436. Any thoughts as to what caused the high readings. I was thinking maybe the O2 sensor or cat is on the way out. Thanks!
Originally Posted by GreenMaxVE
I had my car inspected and the emissions tested today and it just barely passed (previous years had very low levels, nowhere near the limit). Today CO read at .99 (limit: 1.1) & HC read at 273 (limit: 275). RPM's were at 1436. Any thoughts as to what caused the high readings. I was thinking maybe the O2 sensor or cat is on the way out. Thanks!
Make sure they didn't tighten the regs first. But yeah, sounds like O2 or Cat is gone.
I just got through reading this thread:
Failed Emissions - NOx
where I read this:
Says something about cleaning out the CAT using seaform... a good try before spending money on a new CAT.
Oh yeah, if you go with the seafoam, you might need a cool mechanic or emissions shop to let you do a free pre-emissions check.
Good Luck
Failed Emissions - NOx
where I read this:
Originally Posted by eric93SE
NO emissions is mainly controlled by the cat.
I'd reccomend getting a can of liquid Sea Foam, and let the intake slowly suck it in while the enigine is idling (follow the directions).
If you cannot find sea foam, then use regular carb cleaner, unplug one of the vacuum lines running into the intake manifold and spray into the manifold. You can use the whole can (follow the directions).
Both methods will help clean your cat. I've done this before and my emissions are NEARLY ZERO (as good as new!).
Your cat is probably not spoiled, it just aquires a lot of carbon deposits over time making it less efficient.
I'd reccomend getting a can of liquid Sea Foam, and let the intake slowly suck it in while the enigine is idling (follow the directions).
If you cannot find sea foam, then use regular carb cleaner, unplug one of the vacuum lines running into the intake manifold and spray into the manifold. You can use the whole can (follow the directions).
Both methods will help clean your cat. I've done this before and my emissions are NEARLY ZERO (as good as new!).
Your cat is probably not spoiled, it just aquires a lot of carbon deposits over time making it less efficient.
Oh yeah, if you go with the seafoam, you might need a cool mechanic or emissions shop to let you do a free pre-emissions check.
Good Luck
Originally Posted by GreenMaxVE
I had my car inspected and the emissions tested today and it just barely passed (previous years had very low levels, nowhere near the limit). Today CO read at .99 (limit: 1.1) & HC read at 273 (limit: 275). RPM's were at 1436. Any thoughts as to what caused the high readings. I was thinking maybe the O2 sensor or cat is on the way out. Thanks!
Originally Posted by super32
I just got through reading this thread:
Failed Emissions - NOx
where I read this:
Says something about cleaning out the CAT using seaform... a good try before spending money on a new CAT.
Oh yeah, if you go with the seafoam, you might need a cool mechanic or emissions shop to let you do a free pre-emissions check.
Good Luck
Failed Emissions - NOx
where I read this:
Says something about cleaning out the CAT using seaform... a good try before spending money on a new CAT.
Oh yeah, if you go with the seafoam, you might need a cool mechanic or emissions shop to let you do a free pre-emissions check.
Good Luck
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