97 rodeo problems

A partner of mine has a 97 Rodeo 3.2 V6 and he has a major problem. It starts up but has a very rough idle and the check engine light is on. When he puts it into drive it sputters and dies. He took it to a shop and they said it was a clogged cat. That was replaced ($600) and the Rodeo still does the same. The mechanic then stated it must be internal engine damage but couldn't tell what kind of damage it was. Does anyone have any ideas? It doesn't sound like engine damage because the engine does start. I think there are some problems with the electrical when it comes to the idle but i'm not sure why it dies when he puts it in gear.

TIA

I have the same exact engine, and I, like you, doubt that there's internal engine damage from your post. These engines run good and hard and are very reliable.

I'd be likely to get a 2nd opinion and run from this current mechanic :eek7: :uhoh:

The symptoms though, that you are describing sound a lot like what my sister's van is doing. Her's has been diagnosed as being an O2 sensor going out, minute she put's it in gear, it dies. She gives it a lot of gas though right after putting it in gear, and it keeps it going.

To be honest, knock hard on wood :banghead: , I have yet to replace any sensors on my 97 at 125K miles. But that doesn't mean other 97's don't need them sooner.