CVT Start Clutch Calibration - The AUTEL Way

[NeTdEaMoN]

@rustam54 bro I have tried but didnt work , i'll try again, what i'll do is,

Take car on straight road, un plugg the battery for 10 min and plug again, (as it is almost 700KM driven since last battery removal) warm up the car, and than perform the test.

is it correct ?

[rustam54]

Yes, it should work

This method works in Steermatic.

There is only one catch, that your IACV is in the normal commanded range, not open too much at idle, also your TP value is exactly 0.49 at no pedal press.

Temperature between 82 to 95 (i cant recall the exact figure)

If any values dont tell the car ECM that vehicle is not running at factory idle, it wont even callibrate even with a Sacn Tool

[enigsfb]

Assalam-o-Alaikum Everyone!
I have been reading this post for a long time. I own a 08 Honda City Vario. Allhamdullilah, the car is in pristine condition, regular oil changes, changed the CVT fluid twice, air filters, regular cleaning and on weekends I tend to remove the battery to reset the ECU and then do a steering and CVT calibration both using a stapler pin and jumping the 4th and 9th pin in the DLC under the dashboard, it helps to improve the pick up and idling in 'D'. But I have a question, to our experts....there are 2 things.

1 of 2
When I am at a signal and I had stopped from about 30km/h to 0km/h and car is stalled, idling is quite smooth, it's like the car is in Neutral and upon releasing the brake pedal it feels like the car sensed I released the break paddle and it put itself back to 'D' after about 1/3 of a second after the brake was released and the tranny is now engaged.

2 of 2
But when the car is idle in 'D' considering the above scenario that the car is not trying to move forward and brake is not the one making the car stop, now when I release the brake...the car moves forward at about 5km/h and I instantly apply the brakes again....now the idle doesn't seem to be smooth like before. Now It feels that clutch is not fully engaged and the brakes are what resisting the car to move. So do you get it?
It's like clutch is only engaged 80%. Car tries to move even when the brake is pressed, NO DELAY!
(More like in manual car....I have released about 20% of the clutch pedal while the brake pedal is fully pressed, and as I release the brake slowly, the car moves accordingly).

Why does it happen?
Is it because Vario is equipped with a starter clutch rather than the traditional torque converter?

Because I also drive a 08 Honda Civic Hybrid (also a CVT), and it's idle is always smooth and feels like clutch is always engaged 100% when the car is at a signal no matter how many times I release the brakes, the car won't try to move about 1/3 of a second until brakes are released.

Thanks Everyone!

[Xulfiqar]

sounds like your start clutch pack has a warped plate in it, this action is a sign of "stick slip"

You can try a recalibration and see if it helps,

[enigsfb]

Salam Xulfiqar bhai, I have done calibrations several dozen times but it just improves idling and sometimes a slight increase in acceleration but this issue is persistent. Moreover, today I placed two bricks in a way that they pushed both the front tires and then I tried to drive, and in both 'D' and 'L' I was unable to move forward....RPM kept constant at 4000 but despite how much I floor the pedal, car couldn't even cross a brick...it always felt like the clutch never fully disengaged.

And about the answer to my post, I think the correct way for a car to stop is to disengage the tranny completely, right? It should never be trying to move forward until unless I release the brake pedal, like in Prius, Vitz and Passo etc?
It should always slip...or completely disengaged when stopped and act like it's in neutral.

[Xulfiqar]

your transmission start clutch is toasted, you can hookup a honda HDS and see the input shaft sensor readings.you wont have any rpm registering (confirming a slipped start clutch).

[enigsfb]

Xulfiqar bhai...I think you misinterpreted what I wrote earlier about car not moving,by placing the bricks I was trying to simulate a every steep road, I read about the CVT speed sensors....in that case the car never ever moves like mentioned in this thread

Honda City Vario 2008 transmission problems (speed sensor malfunction)

Hi Guys, I have a Honda City 2008 Automatic(iDSI Vario). Mileage = 91k Few Days back it developed a problem when the car wont move forward in "D" or "L" or "S" after i stopped in my office parking. Strangely "R" (reverse) worked. The car was perfectly fine and no major engine tuneups before. I tried multiple times shifting the gears but still no moving forward in Drive mode. With No other options, I left the car there and next morning sparked it and worked just fine. I took to Honda S…

What I meant was like in a manual car when your clutch plates are fried...your car doesn't climb hills well...that is the case here. In Urdu it's like jese "gari me jaan hi na ho....gari zor lagati thi but it was so weak that it couldn't even tapped a single brick".
And I can't cross 120 km.h, when the pedal is fully floored at about 4500 RPM, the car seems to be out of ratios (out of gears like in a manual car when 4th gear's limit is done, it's time for the 5th to kick in) but it seems it has no further gear left.

I will hook up a scanner tomorrow and check the values of Input Shaft Speed Sensors

[Xulfiqar]

And I can't cross 120 km.h, when the pedal is fully floored at about 4500 RPM, the car seems to be out of ratios (out of gears like in a manual car when 4th gear's limit is done, it's time for the 5th to kick in) but it seems it has no further gear left.

All of these are signs of slipping start clutch..

There is only one more outcome here, the variator pulley shafts are galled (the sheave pulleys move in and out and have cylinders to do that, the cylinders are guided by ball bearings and tracks, once the tracks oval out, the sheaves stick or limit movement.

In either case, you will need to see the speed sensor output and also total calculated ratio (HDS will show that)

[enigsfb]

Okay Xulfiqar bhai...thanks a lot for your time. In Sha Allah....an automobile electrician is a friend of mine...I'll borrow his Scanner tomorrow and check all the values In Sha Allah. Thanks a lot. Post the results here tmw. Take care !

EDIT: It's 3:13 in the morning and after hours of reading and understanding about Catalytic Converters I am planning to clean mine as well. Correct me if I am wrong, there are two catalytic converters - primary and secondary. Secondary has to be disconnected from the exhaust pipe and can be cleaned using a stick or slightly wet cloth while the first one has the oxygen sensor fitted in it and located near the coils, I have to remove the O2 sensor and apply some carb cleaner and remove the rusting using a stick...right?

Actually, I'll do all this myself as most mechanics here in Lahore don't even know what a Cat Con is so...I'll take it to the local workshop and ask them to follow my instructions moreover I just ordered bunch of compounding stuff online and plan on compound polishing the car myself in a day or two after wet sanding it. Finally, I have got my summer holidays and this all is gonna be my first project before university starts again.

So Xulfiqar bhai...you are the most famous and reputable Pak Wheeler I know and you're gonna guide me in every phase! I am even thinking to create a separate thread to help people in their I-DSI Vario problems...

[rustam54]

thats a very valid observation. one ought to have a keen observation to notice that.

yes, this is common in these transmissions. If you are driving and you come to a complete stop, the car knows from the vss (speed) zero and brake signal that you have just stopped. thats when you get 1/3 seconds of delay each time. and thats how its supposed to be.

now the next part, its called creep. this vehicle doesnt have a torque convertor. so if you come to a stop and release brake, and instead of driving off, you gradually release brake and then apply full, and so do it once, the car knows that you want to creep.

in that case, it doesnt disengage the clutch fully. I can confirm that the steermatic does the same. Either you come to a full stop from a certain speed, only then you shall have a full disengage. if you partially press the brake pedal and want to gradually move, once the creep is started, it wont disenegage, even if you again come to stop 100%

[rustam54]

Guru, this is common. Steero used to do that.

Its Honda's way of managing traffic slow motion. Not by disengage re-engage, but by partial application

[rustam54]

and by the way, callibration every week is a bit of an extreme. you have to make the car learn itself and save best possible engagements. Most western cars save the jerk information (shift agression) and try to adjust them in the next shift. Thats how they learn and save information over time.

I cant say for this particular CVT.

[rustam54]

I dont know which stage of cleaning you have reached. But you can avoid all that, if you know its actually clogged or not. Source a vaccum gauge and hook to brake booster line. Rev up the engine, if vaccum doesnt drop to zero with time, means there is absolutely no blockage to worry about.

a vaccum gauge is a best asset to diagnose many problems before even grabbing a ratchet to fix something.

[enigsfb]

Correct me If I am wrong....I need to connect vaccum to this black air pipe connected to that black round thing with a clump and one side connected to the manifold I think? Just unplug the pipe and insert a vaccum in that black round thing?

[rustam54]

yes, disconnect the pipe from the black thing (brake booster) and connect it to a vacuum gauge. the readings should be steady at idle. as you gradually increase rpm in PARK or NEUTRAL position, the reading may vary initially, but should settle down the original mark. (or close to it).

What we are looking for is the needle should not drop down gradually to close to zero as the rpms are increase to 4000 (say) and held steady

[enigsfb]

Just went to my local mechanic and he refused to do it....according to him this car doesn't have a catalytic converter.....GD1 has it. But I can see a sensor in the Cat Con.....he said "is gari ki dholki me matti nahi hoti"....I told him like a thousand times that MN3 doesn't have it but LK6 does....and I couldn't even get a vaccum tester. I am in wapda town Lahore....does anyone a good place I might get my hands on a vaccum tester?

I am really getting anxious to check it and somewhat angry at local mechanics. In fact I went to two of them both said the same thing.

[enigsfb]

UPDATE: I disconnected it myself....Started the car...vaccum seemed to work because of the hissing noise. I put my thumb on it and pipe sucked it.....then I accelerated it to about 4500 rpm ....the vacuum seemed to stay the same...I couldn't even feel a hairline notice. So I think Cat's alright?

Btw can a bad cat affect braking?
As it can affect vacuum?
I sometimes feel the brakes are a bit soft because my tires never skid....never below 30km/h.

[rustam54]

You cannot sense vacuum by feel. it wont tell you the subtle differences. I suggest browsing for videos on reading a vacuum gauge.

No mechanic in Lahore may have it. Contact @syncview to assist you in finding one

Regarding your braking being soft, thats a separate chapter to address. Can be air in the system or bad master cylinder seals. or brake lines swelling up.

[rustam54]

and.

a sensor in the exhaust doesnt indicate that the car have a CAT Con. or not.

Usually, CAT Con. equipped vehicles come with 02 sensors. A Primary to sense the air fuel mix (which is the in your car) and a secondary to sense the efficiency of the CAT con.

Please verfiy that you have two sensors in the exhaust, starting from manifold before commencing work. Better yet, do not commence work till you know thats your problem

[enigsfb]

Yes. I've got two sensors in the exhaust. One's right behind the manifold, and one's in the bottom fitted into a rounded rectangular box that itself is fitted in the exhaust.