Tacoma Catalytic Converter & Check Engine Light

Hello, can I get some advice?

My 2011 Tacoma has 234k miles.
In the past two weeks the Check Engine light and Slip Indicator light were displayed.

My mechanic said it's the Catalytic Converter and related pipes.
Very costly repair/replacement.

In the past two days the display lights do not come on.

? Should I risk the emissions test now with no display lights?
? Is my converter ok or is this lack of the display light a false positive?

 

The catalyst monitor isn't a continuous monitor, it only runs the check under certain conditions.

Sounds like either the monitor hasn't run and failed yet or the converters are borderline where they don't fail every time the monitor runs.

As long as the monitors are all ran and passed and you have no codes you should be able to pass inspection.

 

Easiest way I can think of is to get yourself a cheap code scanner to see if the codes are still there. If they are then clear them and drive it. If they come back post the code that shows up. My guess is they don’t usually magically disappear, but stranger things have happened so you never know.

 

Thank you this is helpful!

 

I'd get in for your inspection ASAP. When the light started coming on for me, I reset and drove about 950 miles before it came back on. Reset, made it about 500 miles. Reset, made it about 100 miles. Reset it, made it about 2 miles, lol. Obviously, yours could be failing differently, this is just how it went for me.

Not sure how often your inspections are, they don't have them where I live. Had to have them replaced last year on my 2011, with only 130K miles on them. Sounds like you are doing pretty darn well!

I had cats/manifolds replaced and it was a bit under $2500 for it, using quality magnaflow parts.

 

Our emissions inspection for OBD equipped vehicles is just a connection to the OBD port and they check for codes, one thing I found out was they can detect how recently (miles) the codes have been cleared. One year they told me to go and drive the truck another 100miles and come back for the inspection (I had recently reset the codes).

 

check for exhaust leaks, mine leaked at manifolds to the Y making it run rich and bad MPGs 300 mile per tank

2 gaskets and 6 bolts later was back to 420 miles per tank

 

Could be an anomaly. Had a similar thing happen on my 99 4runner. The lights stayed on for a week and at the point that I was about to buy new cats they went off. I ran it for another 30k miles and never had the lights came on again. It also passed California SMOG every 2 years until I sold it.

 

I have this same problem in my 05 Tacoma 261,800 my mechanic said I had a couple bad 02 sensors but my Cats were fine. He replaced 2 O2 sensors and the light went off for a day and came back on. I'm convinced nothing is wrong with my truck and just clear the codes every year before I take it in to get it inspected. My dad has an 05 Tundra that does the exact same thing. CEL has been on for years. Truck runs great no issues other than that light.

 

If you're popping intermittent P0420 and/or p0430 codes, you can Band-Aid fix with the sparkplug non-fouler trick. It lifts the O2 sensor tip out of the exhaust air stream so it still monitors but less effectively and is less likely to pop the code. Depending on how in depth the inspection is, you may not pass a visual or sniffer test. If they are just looking for codes, you should be good. In order to clear those codes though, you have to complete a few drive cycles. These aren't the types of codes that you can clear with just your basic OBDII reader as they will just reset the CEL but the codes will remain in the 'Pending' status. Another trick would be to get a rear O2 simulator. URD used to sell one but they no longer do, not sure why but I'm guessing they got pushback from the nanny state of CA. There are websites that sell something similar but they are based in a not-so-friendly overseas country so take that how you will, meaning if you do buy them, buy them with a prepaid card that way you keep your banking information safe.

-J