Pyrophilus

Hello,

I am sorry that this isn't the right forum, but I really had no place to turn to. My 2001 Pathfinder (VQ35DE) has been idling rough once about a minute and sometimes stalls during idle. Drives perfectly fine.

Anyway, brought car into dealer and I was just told "no codes", but the "MIL" light is on!?!?!?

Dealer mechanic says that I should get TB cleaning and fuel injector cleaning. I did have codes read about 2 weeks ago and I was told that the engine was running rich.
Car also makes wisp of black smoke during morning starts.

Considering that the dealer is saying it is a "simple" throttle body carbon build-up, or dirty injectors, I am wondering how dirty injectors can lead to rich running engine (wouldn't it be running lean then?). Also, I was pretty sure that most repair manuals says to not clean the TB, because (at least for the pathfinder) it has a special coating to keep it from getting build-ups...

Anyway, the dealer wants $189 plus tax for these two, "for starters" and wants to see how that "deals" with the problem (they sound like local exxon gas station mechanics). Sadly, all three local nissan service is like this (other one charged me $225 to reset MIL light).

I wanted to know if someone thinks dirty throttle body can be cause of rough idle/stalling during idle?

thank you for any help,

E55AMG2

iTrader: (4)

from what it sounds like, you have a few issues going at the same time. One of them is probably a MAF sensor going bad. Another is excessive carbon. Take the car to autozone to have the MIL checked (that is, if its still on) and post the code up here. I can help you more from there

CCS2k1Max

iTrader: (2)

Did the MIL ever go off after the dealer reset it? I can't see there being no codes and the light on unless the $225 charge included screwewing it up too. It does sound like the MAF, but I'd do the TB cleaning anyway (use TB cleaner, not Carb cleaner, which will remove the coating you refer to. The coating reduces, but doesn't eliminate, TB fouling).

E55AMG2

iTrader: (4)

the throttle body has NOTHING to do with this problem. PS throttle body cleaning does absolutely nothing by itself, you have to do the manifold too or basically you just end up with nothing more than 10 wasted minutes and some wasted cleaner.

CCS2k1Max

iTrader: (2)

Let's just agree to disagree.

Pyro, this is for a VQ30DE, but you get the idea. http://www.motorvate.ca/mvp.php/517

E55AMG2

iTrader: (4)

How bout no? Because that is not how you fix his particular problem

CCS2k1Max

iTrader: (2)

What part did you miss in my original post?

Pyrophilus

Guys, no ned to argue. I really appreciate both of your advice. I am currently putting all my time doing body work on my 3rd gen Max, and the car is 60k mi and so I reluctantly agreed to the TB and Injector cleaning (at least they weren't dumping injector "cleaner" into the gas tank and charging me $189, the other dealer did). The guy calls back and tells me that after the cleaning the car was even worse and then they "realized" that the Air Flow meter is clogged?!?! He then told me that perhaps it was partly clogged and cleaning the TB caused more carbon deposit to get stuck in the MAF really tripping it (his exact words!).

I initially thoguht it might be MAF, and courtesy Nissan quoted over $400 for the MAF, so I brought the car in to a dealer hoping that they'd check the MAF (since I have warranty). I guess dealer wanted to make extra $200 through TB cleaning...

I then asked if he means the Mass Air Flow sensor when he tells me Air flow meter. He said yes. I have a question. Isn't the MAF before the throttle body? I never really looked for one (thank God it's okay in my Max), but I thought it was between the air filter housing and the throttle body? If I am correct, how did cleaning the TB cuase carbon deposit to flow against airflow into the MAF???

Anyway, thank God that I still have my extended warranty. As for today, I more than evened out with the initial extended warranty price through the MAF service. I used to think they were crap, but now I realize that maybe it's not so bad after all.

Thanks for all the help,

CCS2k1Max

iTrader: (2)

The answers to your Qs is yes to all, the MAF is where you think it is. Get a new stealer fast whether you have extended warranty or not. God only knows what else they have messed up.