Nissan Repair: service engine soon, crank sensor, nissan altima

Question
Hi.

I own a 03 Nissan Altima 2.5s A/T with 136000 miles.  Its been about 10 month the SES turn on, so i took my car with a friend who had a computer scanner and he ran the computer, so the crank sensor came out bad, I replaced the crank sensor and everything was functioning good, about 2,3 weeks when by and the Service engine soon light turn on again... I keep driving the car with the light on and sometimes the engine would stop when driving at low speeds so after like 3 to 4 months I decided to have it check again this time 3 codes came out, 1. crank sensor, 2. speed sensor, 3. idle high.  I when to a Nissan dealer and got the two sensors, replace them.  The SES light was on for like 10 days and while im driving the car the SES light turns off for like 2 mins. and comes right back...  I really don't know what to do anymore can you please help? what do you think I should do?? Also when I turn the engine off it sounds like a gear or something inside the engine turns for like 2 seconds???

Answer
Everardo,

First, the noise is the engine mounts and it is normal for the noise after shutdown.  Ferro Fluid engine mounts make for a nice idle and firm up after you start driving.  The SES codes should be addressed.  Go to Autozone, Checker or your friend and get the new codes and email me back with them and we'll correct the problem.