Post-traffic engine quiver

I know I sang the praises of my 2000 XJ and I still do. But there is a slight situation that has started to bug me a little and I was wondering if anyone can shed light on this problem. After driving in stop and go traffic for several miles I stop to get something from the store. I return to my Cherokee and when I restart it, the engine seems to vibrate for several seconds before it smooths out and runs normal again. It does not do it if I have been running it at high speeds on the freeway, only after being in stop and go traffic. The Cherokee is the Sport and has the 4.0L straight six. Anyone else experience this? I thought it may be a sensor. I have changed gasoline stations and have had the thorottle body and the injectors cleaned and had it tuned up and all, but she still seems to want to quiver on that post-traffic restart. Any help on this would be greatly appreciated.

The sensor that seems most likely to me is the O2 sensor but that might be premature to jump that far in this fast. Check for any codes first.

The stop and go might be giving a load up on the system somehow.:dunno:

just thinking outloud so far here. It might get someone else to thinking though.

JD

Thanks JD, A guy I know told me it's likely a sensor. No "Check engine" light comes on. It's not real bothersome, but I like keeping the Cherokee in tip top shape and feel a little sting when I have been so religious about the maintainence. It's more of a curiosity thing and a hope that it does not evolve into something more. My '94 had the CPS problem and would stall out completely while going down the road, but this doesn't feel like that.

Have you noticed any smoke coming out of the exhaust when it does this?

Have you noticed any smoke coming out of the exhaust when it does this?
No smoke at all. That's the other puzzling thing. It's like a clean, well mannered gremlin got in there and shakes the engine around just enough to give me something to worry about. No check engine light either. It shakes for about 8-10 seconds. The Jeep dealer mechanic told me it's probably the engine mounts getting weak and another Jeep mechanic said it's probably a sensor. But both said they had not encountered the problem before. I'll probably replace the TPS and the CPS and the engine mounts and see if that does it.