Carbon Buildup Survey
 

The Nissan technical bulletin on carbon buildup says that "The amount of carbon build up is highly dependent on the driving pattern of the customer." I'd like to do an informal survey of those who have experienced this problem to determine if there are predictive patterns.

I am worried because our 2007 NAH has 53K miles on it and was used mostly for driving 30 minutes each way to and from work 5 days a week. We are now retired and if using it mostly for local errands will cause problems I want to know it. Others should know it too.

So I have a little survey:

If you have had problems with carbon buildup, could you please let us know the following information:

Do you have carbon build up problems: Yes or No
1. NAH Year
2. Total Mileage
3. How do you use the vehicle, e.g. 50% local 50% highway
4. How many local trips per week
5. Average distance for local trips:
6. How many highway trips per week
7. Average distance for highway trips


Please give a narrative description of how you use the car in the average week.

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: Yes or No
1. 2008
2. 22K and change
3. 80% local, 20% highway
4. 10 back and forth to work plus a few extra for shopping and gym
5. Average distance for local trips: 5 - 10 miles
6. How many highway trips per week: my commute to work is local except for 1 mile on route 17
7. just a couple of miles at most

my ICE does go on and off a lot so i can understand the buildup...but the engine was not properly designed it seems to break the carbon up.... mine is having the engine heads replaced under warranty.

Re: Carbon Buildup Survey
 

I have some of the symptoms, but my engine has not thrown any codes. As I understand it, they won't do the service until a related "Check Engine" code is thrown, right?

Re: Carbon Buildup Survey
 

My car is too new. It hasn't even reached the first recommended oil change yet. I drive it mostly to/from work, 30 minutes each way, 5 days a week, all city, no highway. About every 2 weeks I do take it on the freeway for one trip, about 45 minutes each way.

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: No

1. NAH Year: 2007
2. Total Mileage: 65k
3. How do you use the vehicle :70/30 highway/City
4. How many local trips per week: 10-20
5. Average distance for local trips: 3-6 miles
6. How many highway trips per week: 10
7. Average distance for highway trips: 50

Commuting daily 40-60 miles each way probably has helped minimize any tendancy for build up, I suspect, though it has shown occassionally rougher starts in recent months, but that seemed to stop after the recent oil change so who knows.

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: No
1. NAH Year: 2007
2. Total Mileage: 71000
3. How do you use the vehicle, e.g. 50% local 50% highway: 70% highway
4. How many local trips per week: 7
5. Average distance for local trips: 2 mi
6. How many highway trips per week: 7
7. Average distance for highway trips: 30 mi

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: Yes or No
1. NAH Year - 2008
2. Total Mileage - 68,000
3. How do you use the vehicle, e.g. 50% local 50% highway - 70% HWY
4. How many local trips per week - 5-10
5. Average distance for local trips: 10 mi
6. How many highway trips per week: 5-10
7. Average distance for highway trips: 20 mi


Please give a narrative description of how you use the car in the average week.
- I commute 20 miles each way to work 4 days a week on a 3 lane highway that is 65 mph. Otherwise, I use the car on 45-55 mph roads around home.

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: No

1. NAH Year: 2007
2. Total Mileage: >65k
3. How do you use the vehicle: 50/50 highway/City
4. How many local trips per week: 10-20
5. Average distance for local trips: 21 miles
6. How many highway trips per week: 5
7. Average distance for highway trips: 15

Commuting daily 21 miles each way. Before converting to PHEV most trips were on freeway during commuter time. Never had any known buildup, but I do have some extended commutes of 56 miles each way which are mostly freeway and >60mph. After finding out about this issue from Nissan service writer friend, who I'd recently shown my PHEV conversion, I did do 3 "heavy" accelerations (with 4 people +150 pounds for the PHEV conversion) onto freeway, during the first of which the vehicle did seem to smoke a little. After the third time (each a separate day) didn't see any similar symptoms. Soon after those accelerations, I took the vehicle on a 150 mile trip from SF bay area to Sacramento and got 38 mpg on the entire trip. I did not use the PHEV kit to assist with the mileage.

I use synthetic oil, changed every 5k.
Most of my daily commute is mixed, dependent on who I need to drop off at school.

Because of the conversion to PHEV, I worry more about the carbon buildup. However, I do use normal acceleration with the ICE to get up to speed and then cruise for distance even in town. I believe that this helps to reduce carbon buildup. I have noticed some light carbon particles on the back bumper that's not near the exhaust (probably gets caught in the wake turbulence behind the car). It easily wipes off (got on my clothes). I attribute it to this type of driving where the ICE starts and then shortly shuts down (I would call it short cycling) while trying to cruise at about 35-40 mph in extended EV mode (I can go WAY more than 20 miles this way). I really try to limit that sort of ICE cycling to try to eliminate that suspected source of buildup. This short cycling would be similar to what would happen when stuck in downtown type traffic.

Re: Carbon Buildup Survey
 

Do you have carbon build up problems: No
1. NAH Year 2007
2. Total Mileage 75,000
3. How do you use the vehicle, 50% local 50% highway
4. How many local trips per week 7
5. Average distance for local trips: 25
6. How many highway trips per week 7
7. Average distance for highway trips 25


Please give a narrative description of how you use the car in the average week.

My wife drives the car to work each work day (25 miles or so) in central NJ on back road and highway driving in various levels of awful traffic. I drive it on weekends to church and shopping trips.

We have had no trouble at all with the car. At our last servicing we replaced the serpentine belt. The Altima Hybrid belt is not the same part # as the regular Altima so smaller dealers might not have it in stock.

Re: Carbon Buildup Survey
 

Yes, I have a 2008 Nissan Altima Hybrid and it is currently in the shop.

Do you have carbon build up problems: Yes
1. NAH Year - 2008
2. Total Mileage - 60,517
3. How do you use the vehicle, 60% city / 40% hwy
4. How many local trips per week: Every day
5. Average distance for local trips: 5 miles
6. How many highway trips per week Every day
7. Average distance for highway trips 30 miles

I'm in Real Estate, so I cover almost all driving types. I usually hit the highway with a 20 to 30 mile trip and then spend all afternoon with short city driving scenarios before heading back home. Warranty company is currently trying to deny the claims.