Toyota Vitz 1KR Rebuild by Rehman Autos[Full case study]

[Thinking]

its in toyota manual. i copied the extracts in some forum. you can search it online too. eating 1L oil/1000 KM is normal and acceptable as per toyota manual.

[siddhi817]

1L oil per 1000km is too much

[Thinking]

good. waiting for details bro.

[mgalaxy3]

1L oil per 1000km is too much

Toyoto knows its newer engines better than us.

That is the 'max' consumption - above that, one needs to find a mechanic or a Toyota dealer.

It's in Yaris as well as Prius manuals

[mgalaxy3]

Sure brother, I think we can we can also discuss this aspect as it is related to the thread. You can also share your good work here.

[speedster_101]

Normally the engine oil is drained/changed at 5000 kms.
1L per 1000 Km means the car would have consumed almost twice its oil capacity till the drain.

[rajaatta]

Yes we will study the rings structure too combined.
And will assess how it consumes the 1 L oil in 1k kms. Later in thread I had written a detailed summary on how it happens so will share it

[siddhi817]

Atta where is your workshop located ? might drop by some random day to discuss my car issues

[paladin]

Tap on his profile, the address is literally written in the location section.

[siddhi817]

thanks mate !

[rajaatta]

Ok so starting again.
So judging the engine from its compression test can easily diverge us from detoriation observation.
For example if a person asks me that his engine compression is 175-200psi. I consider it normal but when he says his compression is 130-140psi then it's also normal for my observation. Then comes the symptoms which are prominent with the compression test. If I ignore the symptoms and just see the compression then my diagnosis would fail. What I do is I see the compression along with symptoms and smoke test and knock retard learning from scan equipment it then clarifies what's going on.

So one thing is sure if we receive a new vehicle with highest auction grades it can be badly abused by its users most of the cases I see in pakistan are of the pathetic engine maintainew by previous owner most the time engine oils are not changed in Japan till 40k and engine oil control rings tends to form sludge in them and it results in failure. But that failure is not seem until we complete 100k kms or low then suddenly it starts consuming oil along with knocking at speed limits of 40-50 km/h.which we misunderstood with octane knock. Which is wrong. So this was the overview of general 1kr engines.

Now coming to ward our brother engine which we rebuilded.

[sk_cooldayz]

@rajaatta

Sorry for being a little off topic. I need your input on a very interesting observation. I came to you with a faulty ABS unit in Passo 2007. Its pressure retainers were not working. As advised I had it replaced from Saddar on Monday.

After replacement, the engine check light was ON but brake was working perfectly. On my way back i noticed that speedometer is not working. BUT with this replaced unit, I observed that car power steering was much much lighter and drive was much smoother. I got mileage of 17km/l for these two days with check light on.

Yesterday, i got the unit replaced again. The check light is off and brake is working fine. But steering is again little harder. Mileage dropped to 13-14km/l and ride is not as smooth as it was with check light on. Mechanic who replaced the unit said that the computer in ABS unit was not working.

Can you speculate what could be the reason. Could it be due to some voltage issue? That other components were getting better current when check light was ON.

Thanks
Hassan

[rajaatta]

Well The first unit you changed was not compatible with the vehicle in result the Speed meter was not working and the ecu shift into limp mode and EPS was also not receiving the speed signal.

So that unit was faulty and muSt be changed which you did the new unit is compatible with the current Wiring loom and needs no major calibration. It will settle down in few days of drive always remember to secure the old part with you as some time it's hard to find compatible brake parts of Passo.
Drive the vehicle on long routes and it will be stabilize again.

[sk_cooldayz]

Thanks - that explains it. Just wondering why car was running so much better in LIMP mode.

[rajaatta]

So the case of this engine we rebuilded was same like we see in routine.
As per our standard sop we conducted the
DIAGNOSTICS First
Which include brief analysis of dtcs and live parameter readings which lead us what's wrong in the engine or what kind of losses are we expecting in the normal engine operation.

2nd step is to confirm the engine health physically. Which is only diagnosed by smoke test and engine compression test.

By performing smoke test it was confirmed that the engine oil control rings and piston bore has been detoriated and fuel efficiency along with smooth power would not be achieved.

So after compression which was 200psi (which is a clear indication of soot layer formation on piston top and combustion chamber's.

Above are the ref fence pictures of old pistons with too much varnish buildup caused by no oil change before import.
This kind of detoriation is seen only on engines which has long or no oil change at all.

[rajaatta]

Disassembling more reveals about situation of the engine.
1st analysis
Pistons were detoriated and bore was also detoriated.

2: oil control rings clearly fails due to sludge formation.
See there is no oil expander visible in the piston oil control ring.

Which is caused mainly due to wrong viscosity and index oil usage as we had discussed many times that these engines are happy with 0w20 or 5w30 and any thing above then that would race up the detoriation speed.

[rajaatta]

So it is confirmed that pistons are detoriated
Now we move towards the crank shaft and connector rod bearings and crank shaft main bearings.

The picture is for reference only not from this engine.
So the rod bearings were not detoriated at all neither the crank shaft had any size issues.

[muddaser_pervaiz]

Can any one guide me what it is all about black water drop coming out from exhaust at morning first start by pushing accelerator bit hard.

[hollywood]

Lol, nothing to worry. All is well.

[muddaser_pervaiz]

Engine oil level after drive around 1200km. Liqui Moly 10w-40 super with oil additive. Shall I top up to max level or drive another few kilometres and then inspect. Meanwhile I got this car with 60k Km driven and as I got this made mistake that I poured 0w-20 made in Japan engine oil and no dis stick level check at that time and after 3700km drive on that oil I come up only 750ml left when I bring car on a oil change dealer he claim car had habit of having thick oil and you poured entirely wrong grade oil so at time first we done engine flush and then add 10w-40 liqui moly super with oil additive. So do guide me is any thing important to check.