glad you found a better dealership! good luck and I hope that your problems are solved!

 

Hi Jojolopes,

I just got my car back last night after execution of Bulletin NTB10-056a. This is my second time in the shop for my Altima Hybrid with this issue (the first time with only 9600 miles on it this time with 17,800 miles on it). The first time it stayed in the shop for 30 (Dec 15, 2009 through Jan. 14, 2010) days and all they ended up doing was cleaning out the "carbon deposits" under the constant telephone supervision of Nissan Tech line. I was told that there would likely be a recall in February 2010 but that never happened. Then last week (Feb 8th 2011) I took it in because the service engine light was on and off for 3 out of 4 days (the first time around, in Dec. 2009 it stayed on). This time they changed the cylinder heads (they assured me that they did it for all 4 cylinders not just cylinder number 4 as the Bulletin states I think). I got the car back last night and so far it is running like a dream! I hope it lasts! I know that there is talk about lemon laws and class action suits on the Edmunds site and I think Nissan has done a horrible job with this issue! http://townhall-talk.edmunds.com/Web...index=.f17d1e4
Wayne

 

I was talking with my local Nissan service writer and he told me that the reason the heads are being replaced is to put in stronger springs.
Another way to help this is to take the car onto the freeway and do some hard accelleration to blow the carbon out, it'll kill your gas mileage. Additionally you could go on some long distance trips, so that the car has a long time at temperature to help remove the deposits.
They used to have gas treatments you could put in your car to help, but I don't know how effective they are with fuel injection.
I've got 60K+ miles on my NAH and haven't had the carbon build up. My commute is mixed and when I drive the car for mileage, I accellerate on gas up to the desired speed and then let the car go into EVmode.

 

I have been having more and more issues with my engine running poorly and also a notable decrease in my MPG's. Initially, I took my 2008 NAH in to a Nissan dealership in TN around 40,000 miles due the altered perfomance to see if their "certified" hybrid technician could trouble shoot it for me. He noted a significant amount of carbon around my exhaust and recommended an engine cleaning that would not be covered under warranty. Other than that, he had no other insight into the potential problem. Now, 20,000 miles later, the engine performance is to the point of almost rendering the car undriveable. I took the car in to my local dealer and was informed that there was significant carbon buildup and on of the cylinders would need to be replaced to the tune of $4,200. I referred them back to my initial attempt to have the issue resolved while the car was under warranty, and due to my research online, was able to convince the dealership to correct the problem without my having to pay for it. However, after finding out how many other owners are having the same issues with their cars, I am interested in finding out some of the other issues that may need to be addressed (i.e. the head, CVT) due to the carbon issue. Thanks.

 

There might be a transmission problem i can say. Even when i was riding my 2009 Altima to office i could not bear the sound coming from my engine, then i visited a service station where they cleaned my exhaust valve.

 

It is a year later. How has your NAH been with head replacement?

My 2007 with 68K miles has been having rough idle and rough EV-ICE transitions. Also, the EV mode is not coming on as much as it used to. Every now and then the ICE stays on at stop lights even after just getting off of the freeway.

Do you think they would do the Tech Bulletin for free as my car is long out of warranty?

 

They might, as that's something more or less to do with one of the longer term items. I can't think of which one right now, but it's worth a shot. If you don't ask, you'll never know.

I am now at 88K and my commute's changed to being mostly freeway. I have converted it to PHEV and I get between 40 - 43 mpg for every tank. If you are continually only driving it around town, you really need to do some freeway driving with HARD accelleration periodically to blow the carbon out.

If I don't do this myself, I end up having some rough starts when it's cold in the morning. I did 3 days of HARD accelleration and then everything went back to normal, no more rough starts. When I did this, the first day, there was a significant amount of smoke (enough that I could see it in my rear view mirror). It wasn't dark, but I could see it!

As before, I still seem to get some light carbon dust that builds up on my bumper that's easily wiped off on my hands.

Bruce

 

Would a good fuel additive do the same thing?

 

might help... try gumout (sp) but there are others

 

I checked today and I don't have any carbon dust around either exhaust pipe. That should be a good sign, right?

BTW, we do not use the NAH for local errands at all due to this concern about carbon build-up. It is mostly used for trips using the freeway. Given that I learned to drive in Southern California where we were taught to get up to freeway speed on the on-ramp so you could merge easily, I always get up to 65 mph on the ramp.

Interesttingly, I got a ticket in Philadelphia for reckless driving one time when I applied the California method for geting on the freeway. Fortunately, the judge saw it my way.