Nissan Repair: rough iddle, blown head gasket, nissan sentra

Question
Hello there; i got rough iddle on nissan sentra w/ 1.8 and
check engine lite bliking while driving ? need advise on where to start looking.

Answer
Hi Hector -

Here are some possible causes for rough idle, in order of probability -

Car needs a tune up - spark plugs, distributor cap and rotor?
Ignition wires
Vacuum leak
Blown head gasket
Fuel delivery problems

You did not give me the year of your vehicle, so I can only give you generic ideas. there a several things that causes rough idle, and you just have to attack them one by one.

Hope this helps -
aloha
calvin