alomst exact same problem; took in to replace a "sensor" and EGR valve and was told BOTH manifolds were cracked and cost to repair was going to be $2,800!!!! i was also told that this was VERY common in the QX line of vehicles becuase they are made from stainless steel and not cast iron and the SS does not hold up to the constant heating and cooling they experience. sure seems like INFINITI would do the right thing and own up to a manufacturing defect and fix this problem out of THIER pocket
Exhaust manifolds were severly cracked and popped when accelerting. Nissan wanted to charge $4k plus. Midas sent them to a machine shop, complete fix at $400 (sigh of relief).
Same issue as everyone else who posted here. We were out of warranty when it was discovered and the dealer wanted over $2800 to repair.
The exhaust manifolds have built-in catalytic converters. Excess heat causes early ones to crack. Loud popping noises are heard on hard accerlation, like merging onto a busy freeway. Your test drive should include merging onto a freeway. Both of mine were replaced under warranty. I recently (Jan. 2011) received a letter from Infiniti that the warranty on these had been extended to 8 years/80,000 miles because they are an "emissions" component.
Cracked manifold. I removed and welded the crack. Hope it holds up cause its a bitch to get off and on.
manifold cracks and engine starts making noise like its a diesel engine upon acceleration and startup
Sounds awful when I accelerate. I really notice it going down an alley. Husband said its a manifold exhaust leak...
2008 infinity cracked exh manifolds trick to removed exh manifolds. removed the 5-6 rear stud
We purchases vehicle from a family member. This problem was present at the time of purchase. My father who Is a seasoned mechanic advised against spending the time and money to fix it at this point because he said it would just happen again because of the material Used to make the exhaust manifold. It is not made to withstand the heat and will just crack again if replaced. According to him the problem is minor and should not progress. It is just annoying. After I've driven a couple of hundred yards the EM heats up and expands and the noise is gone.
I had purchased left/right exhaust manifolds on ebay,plus the studs/nuts for replacing the old ones. My total cost for parts and labor =$1000 at the military car care center..compared to dealer cost $2200. I am very satisfied with the work,the truck runs and sounds great. Thumbs up on the acceration. Moving on to front suspension next. Oh dealership customer service sucks...get your part number and crossrefence and get the hell on......
NO SUPPORT FROM NISSAN...THERE ARE TONS OF REPORTS ON THE WEB ABOUT THIS PROBLEM ....OEM SUPPLIER WAS CHANGED AFTER 2006...BUT FLAWS STILL PERSIST. I AM ON MY SECOND SET OF MANIFOLDS....I HAVE SHOP THAT REPLACES FOR $300. LABOR..I SUPPLY PARTS...WHICH I GET FROM A1AUTO.COM...NOW THERE IS A COMPANY THAT IS INTO CUSTOMER SERVICE.AAAAA
Passenger side at 125000. Took off, welded crack, reinstalled. Works great
NOW, driver side cracked. Grrrr.... Tear down tomorrow. Oh, when removing pass side you must jack up engine and remove motor mount bracket from block.
Heard ticking sound on acceleration. Mentioned it to the dealership but they did not say anything to us about the manifold being cracked until 90,000 miles and an expiration of the warranty. Whatever!
Ther is a ticking sound in my dasboard and I went back to Cerritos infinity and they will not even check it out for me they will not look at it. They said I am out of warrant.
not yet fixed, was informed by dealership about both exhaust manifolds cracked 8 months ago (4/13)
Both manifolds cracked. Very expensive repair!
When engine is cold it gives off a ticking noise when I accelerate.
a craking noise when car is cold,
I own a Infinity qx56 /year2006 exhauust manifolds crack and make loud noise on acceleration.