Please Help Im going Nuts

[jumpsteady724]

Hello everyone i having a problem with my 98 infiniti i30 i got the car about a month ago my (cel) was on i had autozone scanned it they told me it was the knock sensor Speed sensor air intake sensor and (tcm) TRANSMISSION COMPUTER i have change all the sencor and computer but the light is still on i just check the codes it saying its my tcm and speed sensor still plus i got a new code Exhaust gas recirculation system flow problem can someone please help its driving me crazy or should i just not worry about it the car runs good and shift ok to

[Rev_D21]

This shows why throwing parts at a car based on a code doesn't work. I'd have it properly diagnosed at this point because you obviously didn't hit the problem while tossing all that money at it. Time for a trip to the dealer? Codes are just that, codes. They tell the tech what circuit is having issues but codes never mean start throwing parts at it. Get it diagnosed, the only thing I can suggest at this time.

[MaximA32]

All of what Rev said and this:

The EGR System Flow problem is most likely do to the EGR bypass tube. They get a LOT of carbon build-up over the years and just need to be replaced, especially on the VQ30. I would definitely take it to the dealer or another reputable repair shop and have them diagnose it. Autozone is for oil and air fresheners, not getting your car diagnosed.

[jumpsteady724]

So i took my car to the dealership today. they told me that i have a wirer from my speed sensor to the dish board that is broke and the wiring from my tcm and the emc there a problem with it to. my question is can i fix it and how hard is it going to be or should i have the dealership fix it