₦airaland Forum

@Calculation. Yeah, kind of like being busy.
Would try make up suck poat hopefully this year!

Car with timing belts, employ the use of plastic timing bt covers, as a means of protecting the belts(from environmental dust, moisture, etc,), which are known to cause myriads of problems on belts.

Some of the problems associated with exposure of belts(timing) to some of these 'vices', ranges from engine damage as a result of belt getting stuck in to the crankshaft/camshaft sprockets, of such vehicles.

The oil seal located within the cranshaft/cam pulleys, could with time, start leaking. If not noticed early, will generate into a major oil shortage problem(oil starvation),that can damage the valve train(this is a gradual process of wearing out the cam lobes, and bearing caps).

Pls try as much as possible to replace your timing belt covers, when you notice they are broken, or damaged.

These plastic covers are not expensive to replace.

The one shown in the picture here, was the one I replaced from a Honda Accord 2008 V6 engine We recently rebuilt.

Let me try my best here.
Question:
Were the noises there before the overheating job done?
If no, then we can say, all your present experiences right now, stems from the recent job done.

In summary, the timing on that engine, is way out of the threshold (specified marks), specifically the bank 1 cylinder(the one facing the firewall).
The VVTi actuator is either faulty, or filled during installer, or the actuator plastic filter(strainer is clogged with dirts).


If you have other concerns, pls let me know.

Regards,
Joseph

@walexyll. Clients are different. Your comments, kinda suggest a client with a mindset of, "if e no go stop me for road, make e de there like that".
It may be fine with you driving the car with the rattle like that, but this client, just detests that noise always coming up when engine is cranked.

@izaac23.
1. You're not to drain and refill with a synthetic as the case maybe now. Use conventional mineral oil, just for the drains, then you could revert back to your synthetic oil.

2. Auto tensioner is easily seen, and that's the pictures you posted here.

3. How much would it cost? Well, depends on the technician you're working with, and whether if you're buying new, or used.

This is actually howw your engine (1ZZ) looks like. This was from an engine I bought some years ago.

The picture below shows what a valvetrain actually meant.
Although, this is for a 2ZR engine Corolla 2008, as exposed.

Welcome to NL.
Some questions for you:
1. How many miles on the odometer?
This would help us determine the age of your engine internal components, and hence the noise (if perhaps there was any before you took the vehicle to the mechanic).

2. Was there any engine noise before you went for an oil change?

What was that thing he welded from your picture?
What he welded is called a timing chain, autotensioner.
It is spring loaded intern, and operated using engine oil pressure.

Consequences of what he has done?
They are extremely grave here dude; if not quickly corrected, would lead to engine failure (knock).

This would happen in your case, since the plunging action of the auto tensioner, has been permanently arc welded. This increases more than enough stress on the valve train components, leading to engine failure.

You want proof of the above paragraph?
Here we go!

** Drain that oil, and you'd see aluminum filings there, which would definitely clog the oil pump filter, etc.

** Valvetrain components would be already worn out before now.

The fix?!
** Drain that oil, if you've not driven the car for a while now(loads on engine, etc)
This would help reduce or eliminate all the aluminum fillings that might have been lodged in the engine. Do this one or two times, with a new oil filter, and engine oil refilled.

** Replace that timing chain, auto tensioner (what he arc welded).

** Replace the VVTi(camshaugears), if that hasn't failed yet. Be absolutely sure that, the noise you may have had, before you took the vehicle to him, was not a cold start VVTi problem.


Hope this helps you fix that engine.
Hope this helps you out there.

@mikkyjay. Great you found the write-up, encouraging.

New and old camshaft gears

Old and new cams placed side by side, ready for installation

Cam gears

How new camshaft gears looks like

Old or bad camshaft gears removed, and placed side by side.

Intake/exhaust camshaft gears shown replaced.

Figure shows the replaced camshaft gears, and where I positioned the robe used in fastening the timing chain, and tightened it on one portion of the bonnet.
I don't need to spend much time, removing the timing chain cover. You can actually replace or do a job like this, without the timing chain pulled off.

Figure shows the removed camshaft bearing caps, and how placed side by side in an organized manner.
Don't mix or interchange the positions when arranging.

Intake/exhaust camshafts, with the new camshaft gears installed

That's the engine camshafts, etc, exposed.

4. Be organized, and pay attention to the timing marks on the camshafts, and crankshaft pulley marks.
5. Loosening the camshaft bearing caps was started from middle to outside.
Always be careful when loosening the 10mm/12mm, so they don't get snapped.
6. Use some kind of robe, to secure the timing chain, after removing the auto tensioner, to prevent it from slipping into the engine.
7. After removing all the camshaft bearing caps, and placing them somewhere, in an organized way, slide, and remove the camshafts.
8. Used a 17mm socket wrench, to break loose the bolt fastening the camshaft gear to the solid shafts, before fixing the new one

PS: apply some silicone grease to the new camshaft gear, before affixing to the camshafts.

9. Install the camshafts, and cross check everything you've undone in the reverse way this time around
10. After parts replacement, engine started, and allowed to run for a few minutes.

Diagnosis
Diagnosis/fix:
1.Replicated the problem, and sure enough, it occurred again.
2. In this case, there wasn't a check engine light on the dashboard. This tells you, this fault was a mechanical one, which necessarily wouldn't trigger the light.
3. Engine was turned inorder for #1 piston to be at TDC(top dead centre), making sure that valve cover (s), removed.

@automoto. You can get a used one, but you got to be careful with the part number, considering that, the used one you might get, could be same defective one too.

It's a known fact that some modern Toyota vehicles, with Toyota's VVTi cam gears (or phasers, according to Ford motors), have been known to make such rattling noises, on start-up anytime the engine is cold.

This problem, has been diagnosed mistakenly in some climes, to mean, a bad engine, that needs urgent replacement.

Some have also diagnosed such noise on start-up, to mean, that the oil pump or connecting/crankshaft bearing caps and/or crank journals are failing.

With the cost of goods and services increasing daily, motorists would be happy, to get an alternative to engine replacement, if such situations presents itself.

Some symptoms of this problem?
1. Well, on start-up, when the engine is cold, a rattling noise comes from the top cylinder area of the engine.
If you're not careful, would mistaken this noise for engine knock.

2. No matter how you keep changing engine oil viscosities, thinking, a more viscous oil would make any change.

3. The noise gradually increases, and could lead to engine damage(siezure), and engine replacement.

So how do you fix this?
1. The ultimate fix to this is to order a BRAND NEW CAMSHAFT VVTi gears or phasers for the intake and exhaust.
Ensure the part number on the gears matches that recommended by Toyota.

CASE STUDY
Car: Corolla 2008
Transmission type: Autos
Engine capacity: 1.8L

Customer complaint:
At every cold engine startups, rattle noises occurs, and disappears, within seconds, until, another cold cycle start-up is required.

Price?

Nothing would ever stop an engine smoking as a result of mechanical issues. It's just a temporary fix(you're masking the main problem: valve seals are the problems).

Get the car scanned first, before you go from there.

Is this not still tht same Honda Civic, that those panelbeater, mistakenly burnt those wire harnesses, that caused the DC-DC converter destruction?

My thoughts:
1. All the jobs done on the car, in an attempt to make it start, are just waste of resources and time.

2. I'm thinking, just like other hybrid vehicles i have worked on, it could be that the oxyacetylene flame used in the welding process, "mistakenly" burnt some of the high voltage cabling circuits, routed, under the car.
Shorting HV wires ot cabling, would only, just like other electronic systems, blow up the hybrid battery packs safety switch (fuse).

3. This may have damaged the high voltage components (inverter, HV contactors, and battery smart unit-ecu)
of your car.

4. Nothing would ever get the car to come back alive, if the root causes isn't followed logically.

5. I can see from the picture, that the hybrid pack battery location has already been opened, probably, for diagnosis.

6. Isn't it possible for all the burnt wires/harnesses to be identified, where they are routed to, components they input/output, so that repairs or replacements can be made?


I feel your pain dude, wished vehicle was in Lagos though.

That's how a hybrid electric Hyundai sonata looks like

If you intend to remove and replace the hybrid battery pack of this vehicle, the procedures explained in my write-up on my website, can be replicated on other hybrid electric vehicles.

Be extremely careful when working on high voltage system, as you may meet same during disassemble.

I have got awhole lot of pictures on there, to put you through the process.


https://www.dxta.net/2021/12/11/hyundai-sonata-hybrid-2012-how-to-remove-the-hybrid-battery-pack/

If you intend to remove and replace the hybrid battery pack of this vehicle, the procedures explained in my write-up on my website, can be replicated on other hybrid electric vehicles.

Be extremely careful when working on high voltage system, as you may meet same during disassemble.

I have got awhole lot of pictures on there, to put you through the process.

Well, i think, I'd just make sure i get those dead hybrid electric vehicles, and buy them. At least that would cushion in some of the fuel consumption issues na.