I went to trade for a 1998 Jeep Cherokee Sport 4.0, 176,000 miles. Watching it idle it would rev up and then back to idle. When i drove it it seem to not want to go then all of a sudden it would lurch forward. Done that a couple of times and the seemed to drive okay until it sit and idled again. CEL was so autozone put a code scanner on it and got an 02 sensor code also got a p1694 code about no received messages from ecm. 1.possible bus line open. 2. ecm failure. Now i dont know where to trade for it or not. Head liner was sagging, paint was faded in 3 or 4 places, drivers seat broke, tires not bad but could use new ones, AC did not blow cold air, forget to try heater and radio and seemed to have some play in the steering. Everything except the p1694 code i could fix fairly cheap but what about the p1694 code? Is that gonna be expensive? The vehicle i was going to trade even for needs some work done as well. Any ideas on the p1694 code what it is and cost to fix?