Advice on cat converter
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Member
Joined: May 2016
Posts: 31
Likes: 1
From: TX
Advice on cat converter
2-3 months ago bought 2009 5.4L 100k. I want to do the right things cause I plan on keeping it a long time. I'm aware of most all basic maintenance. Truck runs very good; no rough idle, engine sounds good, I do want to flush the tranny but gotta save the money. After a month or so the engine light came on. Finally took it to Autozone and it came back with P0420 code "Catalyst System Efficiency Below Threshold, Bank 1"
Is Bank 1 the first O2 sensor or the one behind the Cat Conv?
Right or wrong, waste of money or not, the engine light came on after I used Seafoam into throttle body. Subsequently I used a CRC brand that's similar into the throttle body.
I've used Techron complete fuel system, CRC 1 Tank Power Renew (which actually gave me 1mpg increase in town.) Lucas fuel treatment.
Now I just put in CataClean and am running it.
Other than replacing O2 sensors and Cat, any other suggestions?
Again truck runs good but MPG is roughly 15.5 hwy, but that's 75-80mph. I drive long distances for my work so I really can't always go 60mph to get better milage.
If I do replace Cat and sensors where do you recommend I purchase them?
I've had a difficult time finding one exactly for my truck. RockAuto is the only place I've found specific Cat for my pickup. All I care about is MPG because I drive so much for work, and I need a truck because my work takes me out on farms plus I haul and pull things in my personal time.
Should I ignore it? Will I get better MPG by replacing sensors and Cat?
Side note, the MPG that my truck shows is consistently .5-.8 mpg higher than my pen and paper calculation. So don't always trust what your truck says, it may be close.
Thanks in advance.
Is Bank 1 the first O2 sensor or the one behind the Cat Conv?
Right or wrong, waste of money or not, the engine light came on after I used Seafoam into throttle body. Subsequently I used a CRC brand that's similar into the throttle body.
I've used Techron complete fuel system, CRC 1 Tank Power Renew (which actually gave me 1mpg increase in town.) Lucas fuel treatment.
Now I just put in CataClean and am running it.
Other than replacing O2 sensors and Cat, any other suggestions?
Again truck runs good but MPG is roughly 15.5 hwy, but that's 75-80mph. I drive long distances for my work so I really can't always go 60mph to get better milage.
If I do replace Cat and sensors where do you recommend I purchase them?
I've had a difficult time finding one exactly for my truck. RockAuto is the only place I've found specific Cat for my pickup. All I care about is MPG because I drive so much for work, and I need a truck because my work takes me out on farms plus I haul and pull things in my personal time.
Should I ignore it? Will I get better MPG by replacing sensors and Cat?
Side note, the MPG that my truck shows is consistently .5-.8 mpg higher than my pen and paper calculation. So don't always trust what your truck says, it may be close.
Thanks in advance.
Senior Member
Joined: Oct 2012
Posts: 2,462
Likes: 717
From: SF Bay Area
First of all, a 02 sensor isn't a big deal to replace. Less than $100 usually. "Bank 1" will have to be identified, but since it's a V8, it may be the left or right side. Google is your friend here.
A 30 second search yields:
http://www.google.com/url?sa=i&rct=j...68217561808987
and:
https://www.google.com/search?q=2009...VNpYbvUzMnM%3A
As far as the cat goes, who told you yours is bad? You have the OBDII system, and so *should* have 2 - 02 sensors. But running low efficiency doesn't necessarily mean your cat(s) is bad.
Start with the cheap/simple things. Aftermarket 02 sensors are fine, but from personal experience, I would never buy a cat that wasn't OEM.
A 30 second search yields:
http://www.google.com/url?sa=i&rct=j...68217561808987
and:
https://www.google.com/search?q=2009...VNpYbvUzMnM%3A
As far as the cat goes, who told you yours is bad? You have the OBDII system, and so *should* have 2 - 02 sensors. But running low efficiency doesn't necessarily mean your cat(s) is bad.
Start with the cheap/simple things. Aftermarket 02 sensors are fine, but from personal experience, I would never buy a cat that wasn't OEM.