Hey guys, long story short I work on older BMW's and Nissa Altima is confusing the s*** out of me.

Symptoms we are having is, basically car runs rough, fluctuation idle and after warm up it shuts off.

If I unplug MAF it shakes less, but still shuts off. Also during tests, once car is warmed up and I unplug/plug MAF sensor
car dies instantly. Which /indicates/ to me that MAF is wrong but I'm not sure what's up with these cars. Please let me know.

Also here is a line replaced by her friend:



What is that line and is it two way or one way (check valve)?

Thanks guys, also if you know a good web site to get nissan parts I'm all ears, for example if I need that hose how the heck do I find it online?

Just ordered Maf, EGR and knock sensor from Ebay.

I would check for codes first. Altima's are known for bad distributors. Unplugging the maf tells me its working. You should clean the maf and the throttle body. Knock sensor will not cause any running problems. It will only set a code. The vacuum line that you have pictured is to the evap canister. I work on nissans and have never had to replace a egr valve. The egr backpressue transducer is the only thing I have replaced.

Thanks for your response, regarding EVAP canister, the line I circled, is it two way or does it have a check valve to block air out?

Codes we have is EGR SOLENOID and KNOCK SENSOR. I ordered both but not sure what to do if car still those issues. When I unplug MAF car idles way better (no shacking).

Thank you!

That hose is standard rubber hose - nothing special.

Altima FSM: http://www.nicoclub.com/FSM/Altima/1997/

The evap canister valve pulls vapor off the fuel system when commanded by the ecu.
If the egr valve solenoid is on all the time it will cause a rough idle. Unplug the vacuum line to the egr valve and see if this helps.
When you unplug the maf sensor it puts the computer in default mode. This may cover up the true problem.
I have also seen a lot of intake gaskets leak. Usually around (1) intake port. Spray some brake cleaner around to test for vacuum leaks.

Also have seen carbon build up in intake an cause rough idle and misfire the intake gasket is what I would dudjest.the distributors would go out and would not redraft tol cooled off

dude when BMW repair questions are ask to me i assure that the car is fully checked. since you said that youve got problems with the shakes, it may cause by wrong plugs.