TSB update causing bad idle?

turbo sol

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I've got a few things I'm trying to work out. (maybe you've seen my other thread)​

But the dealership did an ECM reflash for a safety TSB (where you push the brake and gas to make the engine decelerate, incase of an issue like GM)

since I've got it back it has a noticeably rougher idle.

Is this a side effect?

//full disclosure, Im dealing with O2 sensor issues - so maybe thats more of the culprit//
 
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How many miles have you driven it since you got it back? My first guess would be it's just the ECM re-learning the long-term fuel trims since these would have been wiped during the re-flash. If you haven't driven it much, I say just wait and see if it corrects itself.
 

//full disclosure, Im dealing with O2 sensor issues - so maybe thats more of the culprit//​


Make sure you ensure that your MAF has been cleaned before chasing down O2 sensor problems. Most Toyota models seem to require cleaning every 25000km or so to keep it at peak performance! A dirty MAF sensor will show you a variety of lean codes.​
 
Whenever the battery is disconnected for more than about 5-10 minutes and/or an ECM Calibration Update is performed the vehicle will default to stored values. In other words, the vehicle loses its "learned values" memory and resets to factory default. So what you may experience is rough idle, sluggish acceleration, and slightly odd feeling shifting for a 100miles or so until the vehicle gets its head back on straight.

Typically I like to leave the vehicle in the stall for about 5-10 minutes at idle with no loads on (no A/C, lights, radio, ect.) to have it re-learn idle properly. Then inform the customer that they may experience some slight performance issues until it relearns itself.

You can always force this reset by disconnecting the battery for about 10minutes. I do recommend you let the vehicle idle for about 5-10 minutes with no loads and then drive it a good 20 miles or so afterwards. It will still take a few drive cycles to relearn itself completely though.

Also another point is that if the MAF and/or Throttle body are dirty, when the vehicle tries to relearn itself, it may not learn proper values as the dirty MAF and Throttle Body can skew the sensors which the ECM uses to calibrate itself.
 
The idle does seem to be getting better.

I'll redo a MAF cleaning. in regards to the CEL.

I had
p0136
p2238

Reset the codes and waited for them to be triggered again and got

P2238 O2 Sensor Positive Current Control Circuit Low - Bank 1 Sensor 1
P0171 CEL code (bank 1 too lean)
P2195 = Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1).

With multiple errors for b1s1, I replaced the passenger side upper o2 sensor. (it was still the OE sensor.)

I was able to go about 300 miles this weekend (short road trip) with no issues, but then the CEL (VSC/VSC off) lights came on. for the last 40 miles.

the codes are

P0136 (b1s2) - replaced last year
p2270 - VSC?
p2271 - VSC?

hopefully with a good MAF cleaning, things will work out. :)
 

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