No Cat, Would The O2 Sensor Mess Up That Bad?

[chris123]

So the guy before me cut the catalytic converter off and moved the muffler under the cab with the end of the exust just behind the cab. I do have the 3 wire o2 sensor infront of the muffler, but there is no one wire sensor behind it. My truck does run rich, misses, and bogs down when I give it gas giving me horrible gas milage.

 

I know the best thing to do is rip out this mess and replace everything, but is there anything I could do to fool the truck in thinking the sensor was working correctly? Also, I've replaced the wires, cap, EGR valve, air and gas filter.

 

Thanks for your help,

Chris in Tampa Bay

[2500ak]

I always thought that the rear o2 sensors were just there to measure emissions, at least thats how it is on the newer trucks. I could be wrong. Have you tried cleaning the MAF sensor?

 

Edit:

Did the TBI use a MAF? Seafoam might be worth a try.

[Genuinefine409]

So the guy before me cut the catalytic converter off and moved the muffler under the cab with the end of the exust just behind the cab. I do have the 3 wire o2 sensor infront of the muffler, but there is no one wire sensor behind it. My truck does run rich, misses, and bogs down when I give it gas giving me horrible gas milage.

 

I know the best thing to do is rip out this mess and replace everything, but is there anything I could do to fool the truck in thinking the sensor was working correctly? Also, I've replaced the wires, cap, EGR valve, air and gas filter.

 

Thanks for your help,

Chris in Tampa Bay

 

It could be a bad oxygen sensor however you don't need a cat on that truck. 1996 was the first year for the OBDII and a sensor after that cat.

 

TBI didn't use mass air sensor. There are several things you can check including, EGR, oxygen sensors, injectors, and fuel pressure regulator. Also, check the ignition side of things such as the plugs and wires. they would be the easiest by far to check. you can ignition problems and not burning the fuel right. But back to the cat, it's good to have one but not having one will not affect the way your truck runs, if anything most people state they run much better after removing them. They also get more of a rumble out the exhaust with no cat.

[chris123]

So the guy before me cut the catalytic converter off and moved the muffler under the cab with the end of the exust just behind the cab. I do have the 3 wire o2 sensor infront of the muffler, but there is no one wire sensor behind it. My truck does run rich, misses, and bogs down when I give it gas giving me horrible gas milage.

 

I know the best thing to do is rip out this mess and replace everything, but is there anything I could do to fool the truck in thinking the sensor was working correctly? Also, I've replaced the wires, cap, EGR valve, air and gas filter.

 

Thanks for your help,

Chris in Tampa Bay

 

It could be a bad oxygen sensor however you don't need a cat on that truck. 1996 was the first year for the OBDII and a sensor after that cat.

 

TBI didn't use mass air sensor. There are several things you can check including, EGR, oxygen sensors, injectors, and fuel pressure regulator. Also, check the ignition side of things such as the plugs and wires. they would be the easiest by far to check. you can ignition problems and not burning the fuel right. But back to the cat, it's good to have one but not having one will not affect the way your truck runs, if anything most people state they run much better after removing them. They also get more of a rumble out the exhaust with no cat.

 

 

 

Thanks Genuinefine409, I didn't think the missing cat would cause it to become worse over time. I'm going back to square one of reviewing what I got and change out the basics again, then to the injectors/pressure.

[chris123]

So the guy before me cut the catalytic converter off and moved the muffler under the cab with the end of the exust just behind the cab. I do have the 3 wire o2 sensor infront of the muffler, but there is no one wire sensor behind it. My truck does run rich, misses, and bogs down when I give it gas giving me horrible gas milage.

 

I know the best thing to do is rip out this mess and replace everything, but is there anything I could do to fool the truck in thinking the sensor was working correctly? Also, I've replaced the wires, cap, EGR valve, air and gas filter.

 

Thanks for your help,

Chris in Tampa Bay

 

It could be a bad oxygen sensor however you don't need a cat on that truck. 1996 was the first year for the OBDII and a sensor after that cat.

 

TBI didn't use mass air sensor. There are several things you can check including, EGR, oxygen sensors, injectors, and fuel pressure regulator. Also, check the ignition side of things such as the plugs and wires. they would be the easiest by far to check. you can ignition problems and not burning the fuel right. But back to the cat, it's good to have one but not having one will not affect the way your truck runs, if anything most people state they run much better after removing them. They also get more of a rumble out the exhaust with no cat.

 

 

 

Thanks Genuinefine409, I didn't think the missing cat would cause it to become worse over time. I'm going back to square one of reviewing what I got and change out the basics again, then to the injectors/pressure.