[Labsy]

Hi,

I am not sure this is related, but my 2010 Pathfinder V6 3.0 dCi is more and more weird regarding shifting. I am aware of probably oil need to be changed (half a second engaging delay on green light), but this shifting issue is becoming more and more annoying. Sometimes (and lately becoming this his regular behavior) at speeds below 40 or 50 km/h, when I need acceleration, it goes with revs as low as 1000 rpm and does not want to shift down, even if I floor it. So It comes to a problem at trying to jump infront of other vehicle and it simply does not go, or driving curved roads when you need to pull out of curve, but it has no power at 900 rpm...awful to drive lately.

Might these TC be guilty? I only have DIY bluetooth OBDII scanner via Android app.

P0100: Mass or Volume Air flow Circuit Malfunction
P0110: Intake Air Temperature Circuit Malfunction
P1525: Air Bypass Valve System
P0571: Cruise Control/Brake Switch A Circuit Malfunction

Or one other possible reason: I installed this TDI-TUNING box a month ago. At first it seemed it drastically added power and acceleration, but now all calmed down, plus this shifting issue. I am not racing with vehicle, only occasionally push it down some more, nothing drastical.

 

[landmannnn]

I know the auto transmission computer is quite closely linked to the engine, I even read that the transmission controls the turbo to some extent.

My guess is that those fault codes are interfering with the transmission function. You probably need to get them fixed first.

On the other hand, a delay in transmission engaging is a sure sign of low or worn out fluid. So another job!

As for the codes....

The first two seen to relate to the MAF. Double check it is plugged in and give it a clean with MAF cleaner.

1525 is apparently one to ignore.

The cruise control switch on the brake switch should be quite easy to solve.

I'm not a fan of these tuning boxes by the way. They seem to cause lots of issues with the more complex engines.

 

[Labsy]

landmannnn, thank you very much!
Quite a lot of what you said I assumed even before. Regarding Cruise Control trouble code I thought it was related to other gas pedal and cruise codes some time ago, when I had faulty steering wheel spring for steering wheel controls. Others are cleared, but this one (P0571: Cruise Control/Brake Switch A Circuit Malfunction ) remains. You say easy to fix... switch on brake pedal?

MAF got proper cleaning twice, also contacts cleaning and greasing with silicon paste, so I guess I did my job. Maybe needs replacing?

Regarding Intake manifold temperature sensor...is this all in one with MAF sensor?

 

[landmannnn]

There are two switches on the brake pedal, one for the brake lights and one to knock off the cruise. You've probably knocked the cruise one with your foot.

The MAF does the intake temperature and the air flow. So it could have an issue... If you look for the intake temperature on Torque you can see if it matches up more or less with the ambient temperature (maybe a bit higher)

 

[Labsy]

There are two switches on the brake pedal, one for the brake lights and one to knock off the cruise. You've probably knocked the cruise one with your foot.

Hmmm... but if it were out of order, cruise wouldn't switch off by pressing the brake pedal, rite? Coz' in my case it does...or it might rely on brake lights switch as a redundancy. Will check those next week.Thanx!

Regarding MAF...will also check with Torque, thanx for the tip!

 

[landmannnn]

Sounds like like brake pedal switches are working correctly. I would clear the codes and see if it comes back.

 

[Labsy]

Sounds like like brake pedal switches are working correctly. I would clear the codes and see if it comes back.

Well, thank you for just encouraging me to do right steps. I've already "cleared" Trouble Codes before, but did not pay attention to pop-up note, which warned me about some TCs cannot be cleared while engine running. So this time I cleared them properly and it's been two days, no TC came out! Looks like changing steering wheel spiral cable assembly and cleaning + regreasing all contacts across the engine did the job.

 

[landmannnn]

Fingers crossed!

 

[Labsy]

Update - solved!

All trouble codes cleared out after I replaced malfunctioned brake pedal switch (one of two).

 

[Labsy]

I decided to reopen this thread for weird transmission behavior once again. It is really frustrating, as both, NORMAL and SPORT mode do not shift down with slight accelerator press, but I need to floor it, then it goes 2 gears down and it pulls like crazy with a lot of roaring.

It is really annoying to drive corners and slightly uphill roads, as in both modes it tends to go down to 1200 RPM, he particularly likes to do it just in the middle of a corner, so I have absolitelly no power in exit. Actually, he shifts up in most of the corners, because just before a corner I lift the foot off the gas pedal for a moment and he probably thinks, hey, why not shift up and let RPMs sink down to 1100-1200...and that's right at corner entry, so even if I floor it in exit, it takes a second or two to shift 2 gears down, and pulling moment is both, too late and for slippery road way too brutal.

Is there anything I can do, except to go for MANUAL gear shifting?
Maybe change/upgrade g-sensor, change ATF... or do something with turbo to pull at 1200 rpm already?

Actually, this is so annoying to me, that I am considering to sell the car...

 

[landmannnn]

Have you still got the tuning chip? They can often cause problems.i suggest you remove it.

If you haven't ever changed the transmission fluid, it would be worth doing that job.

 

[Labsy]

Have you still got the tuning chip? They can often cause problems.i suggest you remove it.
If you haven't ever changed the transmission fluid, it would be worth doing that job.

Well...yes, I do have tunning in place and I might really consider going back to those guys to patch back original maps into ECU. Might be that guilty, because I never drove without it to tell the difference. ATF was changed maybe 100.000 kms ago, so I will consider this, too.

 

[landmannnn]

You mentioned the TDI tuning box previously, shouldn't be too hard to unplug it from its various connections to see if that is causing the problem