Diagnosing Hesitating/Misfiring X35i with No Codes

[ClutchKickChris]

You know what, at this point for $40 I'll try it.

Also ordering a new heater control valve and Vapor Canister Purge Solenoid since they also need replacing. This car is a never ending problem lately...

[SB1120]

Well a purge solenoid if leaking can be a contributing factor to a misfire/stumble. What code were you getting for that?

[ClutchKickChris]

Originally Posted by SB1120

Well a purge solenoid if leaking can be a contributing factor to a misfire/stumble. What code were you getting for that?

Here it is:

DME/DDE (Engine electronics):
Error code: 3163
Fuel tank ventilation system, shutoff valve: clamped open, Fault currently present, no matching perceived symptom, Fault can activate a warning light (emission warning light or engine warning symbol)
Environmental conditions:
- Frequency: 1
- SAE fault code: P149D
- Logistic counter: 40
- Kilometer reading: 181208 km
- Engine speed: 2160 1/min
- Fluid level in fuel tank: 54 l
- Filtered factor, tank-venting adaptation: 1.5 -
- current battery voltage: 14.43 V

[SB1120]

Originally Posted by ClutchKickChris

Here it is:

DME/DDE (Engine electronics):
Error code: 3163
Fuel tank ventilation system, shutoff valve: clamped open, Fault currently present, no matching perceived symptom, Fault can activate a warning light (emission warning light or engine warning symbol)
Environmental conditions:
- Frequency: 1
- SAE fault code: P149D
- Logistic counter: 40
- Kilometer reading: 181208 km
- Engine speed: 2160 1/min
- Fluid level in fuel tank: 54 l
- Filtered factor, tank-venting adaptation: 1.5 -
- current battery voltage: 14.43 V

Ok, well if it’s stuck open, Fuel vapors will be drawn freely into the engine which will throw off the mixture, o2, etc. If that’s your stumble, that would be great

[ClutchKickChris]

Originally Posted by SB1120

Ok, well if it’s stuck open, Fuel vapors will be drawn freely into the engine which will throw off the mixture, o2, etc. If that’s your stumble, that would be great

Yes, fingers crossed that this is it.

I'll first replace the valve/hose assembly and test drive, then the oil filter housing cap. Will report back the results

[ClutchKickChris]

Hey guys, so I finally got this fixed...

It was the transmission as I started to suspect!

The past weekend I spent 1.5 days swapping it with a buddy. Overall it wasn't too bad if you've ever swapped a trans before. I did also swap the internal trans ECU to avoid having to re-code the new one. Then of course reset adaptations and drive it slowly for the first 100 miles.

The car drives like brand new, very smooth and predictable.

[ClutchKickChris]

Guys I don't know whqt else to say but I am so disappointed. After 4k miles of awesome perfect shifting performance the problem is back again on the new transmission. Part of me wants to drive this car off a cliff...

[ard]

Well that sucks.

What parts did you pull over from the old ??

[SB1120]

Removed irrelevant post

[ClutchKickChris]

Originally Posted by ard

Well that sucks.

What parts did you pull over from the old ??

I re-used the old mechatronic to avoid having to pay to reset or "virginize" the new used one. I just spoke to a guy who resets mechatronics and he claims the mechatronic is defective and is causing improper valvebody operation which is leading to the stutter feeling.

So I just pulled the spare mechatronic I have to ship to him to have him do the reset.

Still makes me worry that permanent damage has already occurred to my new replacement trans, time will tell... I should have new reset mechatronic in the car by next weekend.