Nissan Repair: 1998 Fronteir Manifold, ca emissions, california emissions

Question
QUESTION: Good day, Sir.
My brother has the '98 Frontier with the extra cab.
His California emissions manifold cracked a month of so before inspection. He couldn't afford the $1,200 for a new manifold so he had it welded as suggested by several mechanics.
The repair got him through inspection and held for a couple of months but now the weld is failing.
He was told by a an employee of an auto parts store that it's possible to replace the California Emissions manifold with the standard manifold.
The guy told him that after he replaces the manifold, the service department at a Nissan dealer can set the truck's computer so that it is taking the readings for the standard manifold rather than the CA EMM. manifold.
My question is, is this true?
Thanks so much for your time!

Joe

PS  I've asked this question before but I just got an automated response saying... "Unfortunately, Calvin Iwashita has been unavailable to respond to your question."

ANSWER: Hi Joe -

My initial concern for you is replacing the manifold with something other than what is designed for the engine? Is it a cost issue? Perhaps you can obtain a used one?

The reason I say this is that there are many sensors and components attached to the manifold, some of them obviously proprietary to the CA emmissions model. Bypassing the system may not be advantageous in the long run.

Just my opinion of course, but I was curious.

Hope this helps -
aloha
calvin

---------- FOLLOW-UP ----------

QUESTION: Thanks for getting back to me.

Yeah, it's definitely a cost issue. It's about $1,000 cheaper for the non CA Emissions manifold.

So, the computer can't be adjusted to match the standard manifold?

Thanks again.

Joe

Answer
Hi Joe -

To be honest, I have never seen it done. However I am just concerned that changing out a manifold like that would present other challenges pertaining to the emmissions systems. The computer waits for responses from all these sensors and "bypassing" them does not sit well with me. I think the proper thing to do is go ahead and call the dealership and see if they really do such a thing, and how much to do so. You just might be better off with the $1,000 more to pay than trying to retrofit.

Hope this helps -
aloha
calvin