One problem related to check engine light on has been reported for the 2001 Chevrolet Prizm. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Chevrolet Prizm based on all problems reported for the 2001 Prizm.
Got the car in 2004. In 2009 the check engine light came on, went to three mechanics to try and find the problem. None of them had a clear idea of what was wrong but they tried various things. It still never went off for more than 5 miles directly after servicing. For a while it was driving fine even though the light was on (over a year) but then it started deteriorating. It was very sluggish, did not drive well (shaking) when going over 35 mph, and the check engine light started blinking for 5-15 seconds when I accelerated. Mpg tanked, went from 35+ to 23-25. Needless to say, I took it to another mechanic. They replaced the spark plugs and fuel injectors and the catalytic converter ($1300 fix on my then 10 year old car). Car started running better, mpg slowly got higher, but after about three days out of the shop the check engine light came on again. Mechanic was stumped, had no idea what was wrong, but he ok'd it for me to continue driving, so I have been doing so. It's still driving well, more or less, but the check engine light is still always on. Around the same time as the 2009 engine light, I noticed the engine was drinking more and more motor oil. Now (2012) I have to put in a quart every full tank of gas, just about.