Exactly. Sometimes you have to have thicker skin to deal with some replies of those who have read and answered many posts of lots of people asking questions. Read what everyone says but dont read into how they type it. So you have two things to look into out of all these replies. Its unlikely both O2s went bad at the same time but I have seen things like that happen. You can replace both of them, but imo, its not the reason you engine is running rough. You can get on here and define " running rough ", that might bring on some more info.
The FSM books and other manuals help alot and can provide alot, but for me I suck at reading a book and learn better on reading others who have had my problems and how they fixed them. Like for example, I can read in my manual how to replace my headlight motor gear, but I learn better by reading how others did it and a video is a bonus.

So grow some thicker skin and get back on here, I want to see you fix it so when mine is running rough, I can read your post to see if it helps me.

 

Thumbs up.

 

I will post what I find out. It will be a few days before I can start on it. Glad that most of the folks on the forum are willing to help out and the info has helped me with a plan of attack.

Cheers

 

The running rough issue is intermittent and sometimes it is only at idle, sometimesnup to about 2500. The car is warmed up at the time, but this problem has started since it has cooled off here in NW Florida. Car only runs at about 177 unless I sit at a light for a while. I am going to change the thermostat with a 195 based on the information I have found on the forum and in the FSM. I have been told by the local corvette shop that the car will not go into closed loop operation until it gets to at least 185. Maybe this will correct the issue. Car used to run hot after I bought it this year and found it needed a new radiator and was in desperate need of cleaning in front of the a/c condenser and between that and the radiator. So, that's where I'm at at this point.

Cheers

 

I've had recent issues with O2 sensors both upstream and downstream of the cats. ACDelco sensors are $26 on Amazon. My 96 is very sensitive to vacuum leaks and loose harness connections. Change the front one first and reset. Check your exhaust connection from the header and eliminate any vacuum leaks on the intake. The code on the rear one is no change on the impulse indicating a bad connection or bad sensor. The PCM possibility exists but is rare.
Last resort is a scan tool session, but sometimes saves money in the long haul of DTC hell.

The car is maxing out the fuel mixture under current conditions and can damage the cat so get it resolved soon. OBDII is a cruel friend.

 

Thanks, the car is parked right now until I can get the time to work on it. Still a lot of things to check, hopefully will be an easy fix. I'll update later
.

 

Did you upgrade the size of the radiator? What thermostat is in the car now? I ask that because 177 degrees sounds low for the temp. after warm-up. The factory thermostat is a 180 which I have in my car and my car runs 195-205 in New Jersey most of the time with the fans reprogrammed to come on earlier. The temp sensor used by the dash gauge is in the passenger side head. You may be getting a misleading reading if that sensor is bad or if there are air pockets in the cooling system (see further down).

Before you change the thermostat I would make sure that is operating properly - could the one that is in there now be stuck open or is it opening too soon? I would also make sure that the cooling system is free of any air - that it was properly bled using the bleed screw on the top of the thermostat elbow. I found that raising the front of the car while using the bleed screw gave the best results in refilling the cooling system and getting all air out of the system.

I would also look at the coolant temp sensor in the water pump - it may be bad and also causing the rough running as that sensor's temperature reading is used by the PCM (engine computer). If there are air pockets, they could cause problems in operation of that sensor.

I only raise these potential issues as you put in a new radiator and possibly this problem can be related to that installation and related things such as refilling the cooling system.

 

No, I replaced the radiator with a stock one from O'Reilly. I don't know how old the thermostat is in the car, but I should have replaced it when I changed the coolant and flushed the cooling system. Shame on me, that's on the list of things to do. As far as air in the cooling system, I only get coolant out of the bleed screw on the thermostat housing and have checked it three times since changing the radiator, so I don't think I have air in the system. I will check the temp sensor in the water pump when I start working on the car again after Christmas and make sure I'm not having any problems there. Thanks for the info and more to come.


Cheers