Should I get new Catalytic Converters? Need advice..

[andy2lock]

Hello everyone and merry christmas!
We have a SR-5 V6 4.0 4runner, great car! We bought the car 2 years ago for $8000 and put about 40k on it. In pretty good condition for having 185K miles on it now.

Just recently drove 7500 miles across country trip to move to California, and we now have problems with our cats. Here is the info:

• P0420 & PO430 code arose a few times the last few months after reset a few times and try with high quality fuel. Right now fuel economy has dropped from about 20mpg to 15mpg.

• See picture of temperature check on Cats + oxygen sensor check. The temp is in front and behind the cats.

Because of california emissions I cannot get aftermarket brand and pass inspection, so replacing all 4 cats & oxygen sensors OEM we are looking at about $4000


Other upgrades that is needed is:
- new shocks (still the 2004 originals on)
- front struts with upper mounts
- stearing gear (rack & pinion)
- valve cover gaskets
- lower ball joints
- sway bar endlinks
these repairs/upgrades will cost about $2600

So total we are looking at about $6000 to tune it into tip top shape.
Appreciate any help/ tips & advice what would make sense to do...? We are very limited with money right now, and won't be able to afford any repairs until march..


thanks!
Andy

 

[telum01]

If I'm reading that correctly, they're suggesting you replace your cats because the o2 sensor readings aren't within spec? Could it be the sensors are the problem and the cats are fine? That's far, far more often the case.

 

[CXS]

Exactly what I was going to say. Stop going to a dealer whose goal is to separate you from your money and find an honest independent shop.

 

[2014 Warthog]

Also, how long had you been driving and how long was the car sitting before getting the test?

Cats need to be fully heated before they work properly, should be driven like 5 minutes at freeway speeds at least before testing, and if it sat for 30 minutes before the test they will cool off.

Been getting an old Toyota truck to pass with that way for 29 years now, original cat and sensors.

Edit: Heh I didn't read that entire page, sounds like they did heat the cats for testing. Would definitely get tested elsewhere first, then as others said, replace sensors and try again. Cats should not go out that fast unless they get really rusted out or get oil in them or some other catastrophic issue.

 

[andy2lock]

The main diagnose telling that the cat's weren't operation properly was the temperature drop as you can see on the picture. The temperature should go up (be warmer on pipe right behind cat than in front?). But it drops.
It seems like an honest good shop and the guy is very thorough and explanatory. Both toyota shop and this independent shop said that they were 99% sure it was the catalytic converters. Could the O2 sensors cause the drop in temperature and also fuel economy drop?

 

[telum01]

The main diagnose telling that the cat's weren't operation properly was the temperature drop as you can see on the picture. The temperature should go up (be warmer on pipe right behind cat than in front?). But it drops.
It seems like an honest good shop and the guy is very thorough and explanatory. Both toyota shop and this independent shop said that they were 99% sure it was the catalytic converters. Could the O2 sensors cause the drop in temperature and also fuel economy drop?

If you're going to defend the diagnosis, why are you questioning it at all?

If an o2 sensor is bad, it won't be sending signals to the PCM saying that everything is in good order.
Without those signals, the PCM is going to keep the engine fuel in an open loop.
In an open loop, the engine will be running rich.
When it is running rich, fuel economy and exhaust temperatures will both drop.
When exhaust temperatures drop, the cats aren't as efficient.
When the cats aren't working efficiently, the o2 sensors will be sending even worse signals.

Everything you've posted can be explained by bad o2 sensors, which go bad far more often than catalytic converters. If you want to replace the cats, go for it and bite that $2000 bullet. But if that doesn't fit it, you'll told to replace the o2 sensors next. Plus, the diagnosis even says to replace the front o2 sensors as well. Do that first. Upstream o2 sensors fail first and more often because they're getting hit by hot, unfiltered, uncatalized exhaust direct from the engine. Replace those, clear the fault codes, and go on driving.

 

[andy2lock]

Thanks for the info and advice! Appreciate it!
It's not that I am defending the diagnostic or that the original question was about that,
my inquiry was that :

say all the cats are bad, is it worth paying $4000 replacing them for me?

The technicians were so convinced they were bad, but I'm hearing otherwise now, so I'm gonna go ahead with the approach previous post suggested.

But if it is the catalytic converters, is it worth changing them, or get a new vehicle?

 

[telum01]

If you end up absolutely having to replace the cats, I'd suggest finding some used ones from a low-mileage vehicle.

 

[Robs08Runner]

Definitely try replacing the O2's first. I would think that there's got to be a cheaper path to take than to pay $6k to keep something that has 185k miles on the road. If you can fix its problems now and can afford a possible transmission or headgasket or caliper job in the future, go ahead and fix it. If not, possibly time to go shopping. The interest rate on a car loan is much cheaper than a lot of credit cards.

 

[andy2lock]

thanks guys! I'll keep you posted on how the repairs go!

 

[SSt4r]

Please keep us posted. I have the same 2 codes (but I may have poisoned my cats).

 

[oljedi11950]

Def replace all 4 o2 sensors usually cheap on amazon ! Back 2 are easy to do ,fronts not so much , should be plenty of posts on this pretty common on 4ths !

 

[BlackWorksInc]

http://www.toyota-4runner.org/4th-gen-t4rs/132953-toolbox-how-use.html#post1272379

Temperatures are difficult to go by as most catalytic converters are dual walled and have some insulation to keep them nice and toasty inside. Not saying its a useless diagnostic method, but its not very accurate beyond a quick check to look for severe temperature differentials that might point to a specific issue.

In the thread I linked above I went over some diagnostic methods and explanation regarding catalytic converter function and diagnosis; its a lot more complicated than most people realize and even shops that specialize in the equipment and diagnostic skills to test them can be steered in odd directions.

 

[97BlackAckCL]

I had all my cats replaced on my 03, but it was still under warranty. If I were you, I would try replacing the o2 sensors first, since it's a cheap alternative to replacing the whole deal.

 

[andy2lock]

Thanks BlackWorksInc, appreciate the link and info!
I guess I will go ahead and purchase new Denso O2 sensors from Amazon, 4 of them?

 

[adrianp]

I'm having to deal with driver side cat as well. My primary mechanic said it would be $700 for parts and $400 for labor ($1100 total). I took it somewhere else to confirm and they also said the driver side cat, but their labor was far less, I think it was like $800 total, but I had to pay for the diagnostic which was $100. Still, if I go with them it's $200 less.

oh and in the past year or two, every once in a while, I noticed a bad smell (I guess rotten egg), and just today read that it's an indicator of a cat related issue. Unfortunately I think, not addressing it earlier may have caused damage to the cat. I may try replacing the O2 sensor myself if they are cheap and see what happens. I just need to figure out which ones I need to order. I recall seeing Denso mention, just need to part #s.

2004 4Runner V6 140K miles

 

[BlackWorksInc]

Thanks BlackWorksInc, appreciate the link and info!
I guess I will go ahead and purchase new Denso O2 sensors from Amazon, 4 of them?

You'll need 2 AFR (Air Fuel Ratio) sensors since your vehicle is a California Vehicle and 2 O2 Sensors for the rear.

 

[CXS]

If it ends up being a bad cat find a good exhaust shop to cut & weld in the replacement. Typical cost is $300-$400 which obviously will save you a lot.

 

[zonianbrat]

Or you could move away from California to somewhere that doesnt test smog! I'm kidding of course.

 

[andy2lock]

Hehe, yes tempting!