New Aftermarket CAT install / Thermal Sensor

With the help of a mechanic at a shop with a sniffer I was able to test my CAT and determine it was bad. After the engine and CAT were warm, he pulled the input wire from the distributor. First turn of the cruiser or it will back fire bad. Then he cranked the engine and watch the CO reading on the sniffer.I forgot what he said was a bad number but I will ask him and add it. By watching the CO reading, he told me my CAT was bad. This is a guy that owns and has been drving Toyota trucks for a long time.

I ordered up a new aftermarket CAT from:

http://www.discountconverter.com/

It was $135.14 + $10. shipping=145.14. Talk to Fred if you call he was very helpful and knowledgable about CATS and emissions.

The old CAT was not too bad to get off. Spray some PB blster on the bolts and let them soak. I just got a big breaker bar and broke most of the bolts when unloosening them.

The CAT bolted up fine but I had to trim the output pipe since it was too long and would not slide in the CAT. I bought 6 new 3/8" bolts with washers on each side and locking nuts. The CAT came with a ferrel and nut which allowed the thermal sensor to bolt right up on the CAT. It came with 2 gaskets for the ends too.

The thermal sensor read "open" on my meter at room temperature. The FSM says it should read 2-200K ohms. It does not say what temperature the CAT is at this reading. I hooked up a meter to the leads and lite up a propane torch and started to heat it up good. The meter went from "open" in a few seconds to like 500M ohms and started to go down fast as I held the torch on it. After about 2-3mins, the sesnor was reading 200K ohms.I turned off the torch and within like 30 secs it was back to reading an "open". It seems like it is working but with the torch that is pretty hot. I wonder if someone else can do this and so we can compare numbers? Also if anyone else thermal senor reads 2-200K ohms like the FSm says at room temperature.

The new CAT is small compared to the OEM one. It has a arrow on the bottom to show the direction.

Hope this helps and please add any information I left out.

The FSM is a bit confusing. The temp sensor is supposed to put the ABV into bypass mode when the cat is too hot. Testing the ABV function is done by shorting out the temp sensor. So low resistance should bypass while high resistance should direct air into the exhaust. Its the "2-200k ohm at idle" that I don't get. I don't know what resistance will switch the input on the emissions computer but 2 ohms sounds wrong. Your torch test sounds right but I'd be carefull not to overheat the thing. The cat is TOO hot at 1450F. The torch is probably at 2500F.

I bought the same CAT from JCWhitney for $89 + $12 for delivery. FYI

Noah said:

I bought the same CAT from JCWhitney for $89 + $12 for delivery. FYI

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That is a deal. I buy tools from JC but never have considered them for stuff like a CAT.

Here is one at JC for $115

JC CAT

These CATS are not California approve I don't think though. The CAT I got is approved for California. Yet another reason why it is more expesive to live in California.

I got mine for $89 b/c they are morons. They told me that i was buying a direct fit CAT made for my LC and when it showed up it only had two bolt holes instead of the LC three holes. When i called them and said WTF they told me that it was for a 4cyl LC. I laughed and then told them that they dont make a 4cyl LC (except diesel). They had to speical order the CAT and charged me the orginal price.
Anyhoooooo, $115 beats the toyota OEM's price of $700 anyday!!

I ordered an 89$ cat from Summit a while ago. They assured me that it would be a direct fit. The cat that showed up was two bolt flanges and no temp sensor. I wasn't up to welding my own flanges so I sent the thing back and ended up with the $300 ManaFre cat. It went in easy and works great. Hopefully the same one is available somewhere else for less - I got mine 3 years ago.

60wag said:

I ordered an 89$ cat from Summit a while ago. They assured me that it would be a direct fit. The cat that showed up was two bolt flanges and no temp sensor. I wasn't up to welding my own flanges so I sent the thing back and ended up with the $300 ManaFre cat. It went in easy and works great. Hopefully the same one is available somewhere else for less - I got mine 3 years ago.

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That sounds like the exact CAT that i first got from JC...they told me that CAT was meant for a 4cyl LC. I got the right one in and it was much bigger

Noah,

JC Whitney did the same thing to me a little over a year ago. They didn't use the "4 cyl LC" comment. It was drop shipped from the manufacturer or distributor. These Cats are sold by alot of internet parts outfits and I identified the model and application that I received, then I told JCW the model number for the one that I needed. They tried to give some argument that the part I wanted was special order and would cost a little more ($15) but I think I said no. I quickly received the correct Cat, no extra shipping, and a shipping label to return the wrong one. Good service, but they can't expect to make money by doing business this way.

Andy