The check engine light flashes, as soon as I turn on the car. When it is in Idle, the engine starts shaking.

There could be a lot of things going on. Here are a few links you should check out. People have had similar problems but have provided a little more detail. I would look at: http://sg.answers.yahoo.com/question/index?qid=20070105182653AAPERxs Check your water pump because that could have caused a domino effect and be causing the shaking because of broken valves. Also, read: http://townhall-talk.edmunds.com/direct/view/.f0d171c Good luck.

Sounds like your flex fuel sensor is bad. The flex fuel sensor helps your truck digest gasoline the has been integrated with ethanol ( Fuel made from corn). Without it your truck will be Bucking specially at startup. Wait to your gas tank light comes on and then fill it up with pure unleaded gasoline. It won't get rid of your check engine light but the truck will run a little smoother.

the check engine light (MIL malfunction indicator lamp) FLASHING and the vibration are both due to a missfire. the MIL flashes to let you know that if you continue to run the vehicle then serious damage can be done to the catalytic converter if it is going away at higher rpms then it may be a vacuum leak. best to get a code reader or take it to a parts store that will check it for free like advanced or auto zone. post which code comes up it will be a P0300 all the way up to P0308 depending on the # of cylinders. a P0300 is likely a vacuum leak bc its a random multiple miss 301-308 are cylinder specific and are likely ignition or fuel injector problems

wow i didnt realize it was for an s10 it more than likely has only 4cyl not many of the s10 pickups came with a 6cyl but its possible and flex fuel wasnt around in 96

My S-10 does the same thing on a particular stretch of road when I am climbing a hill. It is not a serious incline, always in the same place. It starts shaking. I replaced the mass airflow sensor, the engine temp sensor, etc. One time the code said it was plugs. Plugs are fine. Is it possible something electrical? We live on a bumpy dirt road. Something not making connection?

I changed the IAC AND cleaned my injectors. It worked