I recently bought a 2000 Dodge Dakota V6 with 275k miles on it. I had a code for a clogged Cat, so I had it cut out and a straight pipe installed. I still have the O2 sensors in, with a little adapter that the muffler guy said would let the tip of the sensor dip just enough so the code would clear. Had it done yesterday, so it hasn't cleared yet. However, a new code popped up. I do not know if the code appeared on the way home, after the Cat delete or before, since the engine light has been on already. It's the dreaded P1740 code, which I understand it's dealing with the Torque Converter/Transmission. The truck seems to be shifting well both up and down. Question is, since I've been driving around with a clogged Cat and now it's free flowing, would the computer think there is a problem?

 

I get those codes on my 96 2500 on a fairly regular basis. The trans seems to work just fine though. I generally just clear the codes, and then they are gone for a couple months.

 

Thanks. I took it to the trans shop and they cleared the code. I drove it for 250 miles and didn't return. Took it back to them for a trans service and it runs a lot better. They did find the magnet to be caked with metal flakes, and said it was wearing, but when he test drove it afterwards, he said it was fine. Drove about 200 more miles and CEL hasn't returned, so hope it's all good!