97 rodeo running rich? help please

I am at my wits end with this. This would not bother me If I did not love my ride so much. It all started right after I had my clutch replaced. I picked it up and the next day the CEL was lit.
I drove it a few days like this hoping it would reset. It didnt so I bought one of those cheap OBD2 readers. Which gave me a p0174 trouble code. (Bank 2 too lean). I replaced the O2 sensor after the cat (bank 2) I figured it had 100k so it would be time to change it anyway. Cleared the codes and drove it. The CEL took all of 2 minutes to return with the same code. The next day I realized the CAT was getting red hot. It idled more and more rough as time went on. Until it had a serious power loss. I took it to my local MECh who reset my computer with his scanner and he said he thought the Cat was clogged. I changed out the cat and the power was back. but the new CAT was getting red hot again. I check for Intake leaks, nothing. I decided to replace the plugs. They were in pretty bad shape. And there was oil in the plug tubes in 2 of the drivers side holes (not in the cylinder just the tubes) Got the new plugs in there and ran the veihicle. It ran better than ever. I ran it around all day with no CEL and no red hot CAT. Problem fixed? So I thought. The next day I turned on the vehicle to go pick up my wife and as I was backing out of the driveway THE CEL went on. (depressing) Picked up my wife and when I returned I looked under the vehicle and sure enough the cat was Cherry red. The car still ran good and did not idle rough but The CEL and the Superheated CAT were back. Can anyone help me with this? I am about to go crazy dealing with this truck. Injectors leaking? If so how do I know. Any Help will be kindly apreciated. Depressed about my ride.
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that is the problem. I am sure you can only buy them from the dealer and they are a bit expensive...good luck
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Dont think so. Faulty (closed) EGR valve will not cause engine to run rich, it will just increase combustion temperature and fuel consumption. I logged like 20K with faulty valve on my Trooper, changed it, and the only noticeable difference was slightly improved fuel consumption. Primary EGR purpose is to lower NO (or was it CO?) content in exhaust gases.
The valve+gasket itself was like 160$ shipped from St Charles Isuzu. AFAIK Rodeos have exactly the same valve.
Peter
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Your Rodeo has 3 oxygen sensors, one on each exhaust downpipe, and one after the cat. If you've got 100k on the vehicle, it's time to change them all. I suspect you changed the wrong O2 sensor and are still having the same problem. Whatever you do, please post your solution to this interesting problem for the group. Good luck.
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