One problem related to crankcase (pcv) has been reported for the 2001 Jeep Wrangler. The most recently reported issues are listed below.
Another victim of the 2000-2001 Jeep 4. 0l cylinder head cracking between cylinders 3 and 4 on the cylinder head. Cracked head has caused many other expensive problems throughout the engine such as (coolant system failure, crankcase bearing failures, oil pump failure, valve stems being warped, etc. ) after extensive research and being a part of many online polls this is obviously a problem with Jeeps of all models that have the 4. 0l inline 6 cylinder heads of these years. The vehicle was in motion when cracked head occurred causing the engine to overheat as well as oil pressure to drop. Also caused malfunction and ruined O2 sensors on vehicle. The cylinder heads in these 2000-2001 Jeeps of all models are faulty and it is obvious cause Jeep changed the heads the following year in 2002. They claim that these heads are cracking due to the engine overheating. This particular Jeep has never been overheated in order for it to cause the cylinder head to crack. They are faulty.