Why do Automatic Gear Shifts Jerk?

[Xulfiqar]

Yes. The mechanic said the speed sensor or the variator pulley according to you had 3 teeth in japanese verson.

Well, thus the said problem result in the said issue? I mean to ask is the diagnosis correct? Plus if i can get that particular part from somewhere then the same transmission can be fixed?

What is the approximate costnof ECU and transmission box? And which oil is to be used because user manual says ATF while people say CVTF?

that part is not swappable from your old gearbox, its part of the variator pulley which obviously would be damaged on yoru old one, The oil to use is CVT fluid sold by Honda, do not use anything else in there

[Xulfiqar]

Do u know of any mechanic in karachi that may be able to provide me the service and what could be the eatimated expenditure of this calibration?

cannot help you there - however these members maybe helpful
@capsat @syncview @ser_gtr

[taimoorali.khn]

Thanks alot for ur help bro!

[SER_GTR]

cannot help you there - however these members maybe helpful
@capsat @syncview @SER_GTR

I Know Someone With AUTEL Unit Which Can Calibrate It...However I Dont Know If They Do Zero Point Calib As Xulfi Bhai Suggest.....

[SER_GTR]

Do u know of any mechanic in karachi that may be able to provide me the service and what could be the eatimated expenditure of this calibration?

The Matter You Explained Seems Not To Be A Normal Practice For A CVT Trans......You Wont Feel Any Dragging Or Sudden Jerked Deacceleration While You Lift Foot Off Pedal...Something Is Wrong With Trans Itself Or Its Usually Calibration Leading To This Behavior...CVT Behaves As Smooth As It Can And You Wont Feel Anything While You Accelerate Or Deaccelerate...

[taimoorali.khn]

Its not that i feel that drag or jerks at high speed.Infact the car is really smooth at high speeds but the problem that has been described occurs around 20km/h with foot off throttle.This only happens in gearD and neither in gear B or S.Also i know that there r no shifts in cvt but during that drag,i do feel as if the car is downshifting and as if it gets stuck in that gear for a sec or two and then it ends.Please let me know any mechanic where i can get the calibration done?And mind u that there is a slight noise during the drag aswell as if the trans is getting stuck.

[pwuser150710798079]

I have 2013 model Toyota Passo CVT (1000 CC). It's millage is 55,000 a month ago i have replaced the Tramission oil and after few days i am feeling a slight jerk (sometimes) from 1st to 2nd gear shift. i visted Ustad Zahid (queens Road Lahore). he told me that the value body will be replaced or drive few millage the car with high intensity probably the jerk will be settle down automatically.
So what do you recommend me on this.

[waqas.rasheed]

@Xulfiqar
Sir, Required help please.

Possible reason of jerk from P to R only in Automatic Corolla GLI 2015 and its solution?

Recently Tx oil was flushed with Kixx DX-III (a compatible oil of Toyota Standard ATF T-IV). So there is no issue of compatibility.

Initially Tx fluid was not changed till 70K ODO by previous owner. Jerking was also observed before the flushing. Tx fluid pressure was improved from 1.7 MPa to 3.0 MPa after flushing but jerk is still there as soon as Gear shift from P to R or From N to R. This happen only in reverse(R).

any solution to avoid jerk? as I don't want to perform the valve body service at this stage, as I have serious doubts of getting it worse after opening as it is a highly sophisticated part.

[Xulfiqar]

no dexron III is compatible with T-IV, - toyota T-IV is a HFM ATF which is a bit more modified than Dexron III-H.

Harsh engagement can be a hydraulic fault or an electric fault, Find a proper mechanic who can decipher the data being seen on the scan tool.

If you are getting a slam into 1st from N or P, the forward clutch maybe sticking, you will also feel the shifts being too stiff (almost honda type), this can also be caused by too much noise in the electrical system.

Best is to find someone sensible who can use the data being seen on a scan tool, most mechanics in pk just use it as a reader and then throw parts at the car while praying it works.

[waqas.rasheed]

what do u suggest, should I change the Tx fluid to T-IV immediately?
I have consulted @rajaatta for diagnosis, on his recommendation, complete flushing of Tx fluid was done by using DxIII but still while shift to R mode, jerk is felt.

[Xulfiqar]

sounds like the EPC solenoid is faulty if its not regulating apply pressure with engine idling - the harsh is usually a sign of failsafe.

You may get lucky by just servicing the valve body (its not that complex as the older models had). If not then too bad, the EPC solenoid for the 245e gearbox costs about 240 USD in retail globally.

[rajaatta]

yep its looks like EPC is stucked or sticking along with reverse control valve as the fluid was not replaced till flushing.
had done a lot of them with same conditions and bad drain interval services.

[Xulfiqar]

being a toyota supplied EPC, you can flush it with hot ATF and clean out the valve body for about 70% success rates.

Good thing its easy as its under the transmission, I sometimes deal with FWD units with valvebody on the side

[rajaatta]

yes we usually tears down the whole valve body assy and inspect each valve and bore carefully and always found jammed valves or sticking valves in them just clear them out and we are good to go.

[Xulfiqar]

yes, I find that too specially with older transmissions that use T-IV ATF, the T-IV breaks down really fast and deposits material into the valve body tracks which then cause stick.

I have a special hatred for Honda in this case, the valve body is behind the pump and 80% of failures is from some stupid valve sticking in it.

[irfanhaider975]

salam bro.koch din pehlay mai ne gear oil seal, main oil seal.means complete engin kola ta.saray seal chang kiye hai.wo saray problems tu teek ho gaye.par gear chng hotay howe jhatkay marti hai.honda 2003 automatic hai.