CVT Start Clutch Calibration - The AUTEL Way

[enigsfb]

So, I hooked up a vacuum sensor myself and it looks like that Cat Con. is alright. May be it was the fuel quality or what but from the past few days the car feels really responsive on the pedal.

Apparently, it was something called a "NAB sensor" that was actually clogged, it was installed in the manifold. As it had never been unscrewed before it took a lot of effort to uninstall it. Did it today, I really hope the fuel average is back, it literally dropped from 24 km.l on highway to 12.5 km.l. My usual mechanic told me to clean the so called "nab sensor", it had oil in it.

One more thing, the brakes require service too. The brake booster is okay, rear brakes are okay, front discs are not too thin, their width is what seems to be alright but I think my front disc pads are dying. I replaced them a year ago....Frixxa I think. Brakes have become really bad, when I push the pedal completely front wheels never lock, it's a strange feeling like pushing the pedal to the wall with all my force but just brakes are not capable to stall the car at once, no matter what wheels never lock but brake seems alright when I am above 60 km/h.
Any suggestions on new brake pads? or check anything else?

P.S I am planning to get either original ones that costs around 6,300 rupees or maybe a brand I came across known as "CP" it's Korean with three months warranty. Many people say that mostly Honda Cars require to have original brake pads only, the Korean ones don't work that good with these cars.

[rustam54]

Why dont we start a new thread and Tag @capsat , @Xulfiqar and @syncview to address your concerns one by one?

[ghmarri]

Rustan bhai
My city idsi steering is very hard with no light
Can u plss fix it with ur scanner?

[sabeehflying]

@rustam54 hello brother hope you're well.

I own a Honda N One 2013 and had its battery disconnected by the mechanic. And when he plugged it back in, my CVT has started jerking when you let off the throttle while driving.

I've tried the battery removal method and then speed upto 60 and then let the car decelerate on its own for 5 seconds and speed up again 4-5 times with no improvement.

Also now the car is taking a lot more time and RPM to reach even a 100 kph and acceleration has dropped drastically around the 100 mark itself.

Can you advise a solution for this? Since I have checked and can't find any workshop manuals available for this car. Though since it's a 650cc Honda with a CVT, hope you can advise a solution for this!

[rustam54]

ly the much awaited tool arrived yesterday. And I thought of sharing it with fellow members along with posting the first tool application.

The Steermatic battery had completely drained in the past couple of days and the ECU forgot about the CVT start clutch calibration. Sadly this happens everytime if the battery is disconnected or it completely discharges.

So instead of the old "drive upto 60 and decelerate method" suggested in ESM, I thought of putting the tool to some use.

But before I proceed, I must thank the one person who made it possible for me to decide. Without his input, I would have ended up with a wrong choice or some chinese clone.

The one and only, our teacher, our automotive mentor, our guru and our respectful elder brother @xulfiqar bhai.

Hello Sabeeh,

While I donot have any information about your vehicle, I would encourage you to research and identify what sort of CVT setup you have. Meaning, does it really have a Start Clutch or does it have a Torque convertor setup?

And there a some more questions to your information provided:

1. How do you know that its the CVT thats jerking and not the engine itself?
2. Whats the maintenance history on CVT fluid and filter?
3. Why was the battery disconnected by your mechanic and what was the work performed?
4. Any DTC codes present in the vehicle?

PM me the VIN and let me see what I can find about your vehicle

[sabeehflying]

The CVT setup has a torque converter. The engine variant is a S07A (available in NA and turbo) that comes with a CVT only to begin with.

1. Well it's the CVT my guess since the rpm is maintained when I take my foot off the throttle. It's equivalent to someone taking a gear going neutral all the sudden as best I can explain

Jerk is not there at 10-30 kph but at higher speeds like 40 you can notice it immediately.

My throttle was also serviced and the RPM is on the higher end (generally is around the 800 mark but is at 1000 and when car goes neutral shoots upto 1500 and comes back down to 1000 gradually). I will try to get it scanned tomorrow as an N wgn owner told me since it's drive by wire then has to be recalibrated as well. (N wgn and n box share the same engine and gearbox configurations).

1. CVT fluid has been replaced around 18000 kms ago. The car currently has 65000 on the odometer.

2. Well he said a 'tune up' was needed to my surprise and typically removed the throttle body and cleaned it with petrol since the butterfly was full of gunk inside. He was checking my car's dry battery as well and went on to disconnect the positive terminal (later would I know how a grave mistake that was) plugged it on back later.

3. Well my brakes had to be bled after that to my great surprise since it had air in the system. And brakes are also not working as efficient they were since the CVT would do engine braking as you would decelerate. I've had the traction control light pop up but that disappeared once I topped up the brake fluid.

Other than that no check engine light or any other DTCs. So I suppose considering the braking part as well, the CVT calibration is at fault as the car has never had its terminals removed and the problem is immediately there after this.

Yes janab I'm sending you my VIN details in a moment. It's a JG1 model Honda N One though.

UPDATE: TP sensor was causing this issue. Once it was relearned ( For my n one they opened up Honda Prelude on the scanner), it was back to normal and the jerks have completely disappeared.

[pwuser150895891959]

@Xulfiqar @rustam54 Asalam O Alaikum..brothers I admire your knowledge and expertise which are really outstanding, I need some help regarding my City 2005 auto petrol, I owned this car from last 10 years and it was performing like heaven, I don't know who suggested my brother that you guys need to change your gear oil as its life is nearly end, so he did the same thing with the help of some mechanic they changed the gear oil ATF (as written on the oil gauge) and from then this car became a disaster for me, after that the major issues I faced are as follows,

Poor pickup
Knocking Problem
Vibration problem and it became worst on AC, but it all happens on D or R, Car seems very smooth on P or N even on AC.
Fluctuation of RPM
Very bad performance mileage 7 to 8 km/ltr
Generates very irritating ter ter sounds when on low speed like 5 to 10 or on picks (on AC)
Badly jerking

But it all happens in slow speed or on picks, once the car on pace or in constant speed it flies like unicorn. I tried more then 6 mechanics for different opinion but they all have only one solution is to replace the transmission (gear box) with kabli one. I visited the Honda 3S SITE Karachi, and without any test drive or scanning he suggested me the same solution (change of gear box) and when I request him to please check it through scanner or any tool, he told me " bhai humara roz ka kaam hai".. Now I am stuck what to do and luckily saw these forums and impressed by your knowledge, I saw this first clutch calibration, is this helpful for my problem? if yes who or from where this job will done in Karachi? Please suggest me what to do now.. Please respond ASAP

If any other brother can help or suggest me any mechanic in Karachi it will be a great help.

[chabbas]

Just change the oil to Honda CVT oil, as 2003 to 2008 model city comes with a CVT transmission. Try to flush that ATF oil to the maximum, by taking out the oil when vehicle is hot, & raising the vehicle from driver side. Most probably the issue can be resolved; if not than it can be followed by CVT re-calibration, but replacement of trans should be the last option

[rustam54]

they changed the gear oil ATF

Wa Alaikum Assalam.

As brother Abbas mentioned, this most likely seems like use of wrong fluid. For CVT gearbox, ATF should not be used as both fluids have different lubrication properties and friction additives.

Another problem with Honda CVT is that only Honda CVTF is to be used. Any other CVT fluid shall not work or would reduce the usable life of the transmission.

The problem has to be addressed based number of things:

1-Please confirm which oil was used
2-How much kilometers is the car driven since then?
3-How was the CVT fluid level checked? Was it check on a cold engine or hot engine? Low or high fluid level is a disaster.
4-Was there any battery disconnection during this process?
5-Describe the vibration under different scenarios in detail. Steady input on accelerator at a low speed cdrive, does that cause vibration? What is off-idle response? Jerky or smooth or just lacking power?

6-Observe any burning smell on the fluid?
7-what the current mileage of the vehicle. is there any CNG history?
8-When was the CVT fluid changed last time before this, how have you been maintaining your vehicle

All these factors are important to diagnose. It may well be a situation that you may still have to replace your transmission after doing another Honda CVTF flush. And by flush, I mean flush disconnecting the cooler return line, not just drain and refill. CVTF is expensive. About 6k if original from 3S. More if flush to be performed. So bear this cost in mind that it may be a total loss after the flush.

[NeTdEaMoN]

and who was the mechanic/workshop who diagnose the TP sesnsor issue ?

[sabeehflying]

Asked a fellow Honda N series car user they said TP needs a relearn if the electronic throttle is disconnected. Basically any computer scanner guy with Honda HDS scanner can reset it.

[ahsanonline]

Hey rustam bro.

Still got the autel?

[rustam54]

Yep

[ahsanonline]

Any plans on selling it?

Edit: or its services?

[pwuser149883696433]

Hi dear i have city 2004 vario problem in idle when shifting to D S L and R what should i do nw? Can I di claboration? Pls pls pls explain me in easy words... Thankyou

[rustam54]

Please mention the following to let all current users (who may have more experience with their cars) to assist in a diagnosis. I no longer own the vehicle, therefore my access to other possible issues/symptoms is limited.

Exact Nature of the Problem ("problem in idle" is not enough information)
Vehicle Mileage
Maintenance History (when was last CVT fluid replaced? is the idle air control valve working? etc)

This thread has all the required details in "easy words" to help in calibration. You may try that (even without a scan tool) but if the problem is different, the results would not be promising.

Good Luck!

[dms664]

The cvt calibration is necessary after cvt oil change as well which ppl dont do here usually.

[pwuser149883696433]

This issue starts after changing cvt fluid.. car milage is 95k, also checked with scanner no error or code found. Also change spark plugs original ngk average was 11 to 12 on highway with ac and 8 to 9km on local with ac on very light foot

[pwuser149883696433]

This issue starts after cvtf changing

[zainawan6881]

Brother can you please recommend a place in islamabad from where i can get it done correctly.
I am facing vibration and low rpm issues when i shift to D.
Honda city vario'05