DIY SCV Valve Replacement on TOYOTA AVENSIS D-4D 2.0 1AD Engine: Feasibility

Hello!
I have a question. Is it possible to replace the SCV valve yourself in AVENSIS with the D-4D 2.0 90kW 1AD engine? In this engine, there is only one SCV valve on the injection pump (not two - green and red, as in older types). From what I saw under the hood, to dismantle it, you only need to unplug the cable and unscrew two screws. However, does installing a new valve not cause any further difficulties and consequences, e.g. the need to interfere with the "computer". Can this valve be replaced economically?

You can. There will be no complications

Regards

Kagetora wrote:

You can. There will be no complications

Thanks! Then... get to work

Next question.
What is the voltage supplying the SCV valve in the D-4D 1AD 2.0 90kW engine?
5V or 12V

It doesn`t get the tension you would expect in your question

Somewhere I found your previous topic about Toyota.
No offense, but after the level of that discussion, I think you should be able to handle the replacement...
Has anyone checked the pressures at startup and the rest of the parameters? (even correction)

The minimum pressure during starting is 18 MPa, otherwise there will be no signal for the injectors, only above this pressure the computer will allow the car to start, the correction cannot be greater than 1.5 mm3 per second, the manufacturer expects to replace more than three, but this is nonsense

Why do you want to replace it yourself? You can`t install a used one, you have to have a new, modified one

deesz wrote:

Why do you want to replace it yourself? You can`t install a used one, you have to have a new, modified one

Because I have no intention of paying a Toyota service center approximately PLN 600 for removing the plug, unscrewing two screws, removing the old valve, inserting a new one, screwing in two screws and inserting the plug. Additionally, they have to pay PLN 900 for a new valve. It`s a scandal and just plain bullshit. Last Friday, it took me about 10 minutes to remove and install the valve. and it was child`s play. I washed the valve and started it up in kerosene, gently pressing the movable spring element (revealing the transverse through holes). During this activity, I clearly felt that the valve was moving more and more freely. I don`t know how long these resuscitation efforts will last, but at the moment (hopefully not to jinx it) the car starts quickly from the first tick. So this little primitive "shit" is most likely the cause of my problems.
I know one thing - the price of this valve was created in a dream of a madman, just like the price of its replacement service at the Toyota service center.

In fact, it`s a bit much for the replacement alone. I hope the cleaning is enough. I suggest using some fuel conditioner for some time because the injectors may also be slightly tarnished. Regards.

It is true that you only have one SCV, but the information below may be useful because it concerns the replacement of the SCV and will clarify the minds of others (who have 2 SCVs).
In Toyota it`s a breeze, about 30 minutes, in Opel V6CDTI only a super spec can do it - 12 hours of work

Video for Toyota


Useful information http://www.toyotaownersclub.com/forums/index.php?showtopic=87986

And one more thing, you can`t clean the valves, they have a manufacturing defect (they seize mechanically), you can soak them for up to a month and they won`t release.
Denso changed their design and now they are ok.


See for yourself what`s wrong with them http://www.oknation.net/blog/preechasan/2009/03/11/entry-3

After about 6 months of break, the problem with starting my Avka returned. The same thing again - it starts and then goes out. I removed the SCV valve, cleaned it and "started it" in kerosene. After this procedure and installation of the valve, it fired straight away. Fearing that the problem would worsen with the arrival of the first frost, I ordered a new valve at the Diesel-System store (W-wa) for PLN 735. As soon as I received the parcel today, full of satisfaction and confident that the problem would be solved, I went to a diesel specialist I knew. We replaced the valve and... At first, Ava didn`t want to start at all for a long, long time, and when it finally did, it immediately went out. And so several times - it started and went out, which is the same as with the old valve. In an act of desperation, I washed the old valve again in kerosene, installed it and the Avka started almost immediately. Right now, my repairman and I are stupid.
I checked the resistance of the valve coil in hopes that it might just be open, but the ohmmeter showed 2.7 Ohms.
I`ll call the store tomorrow and try to explain something. The worst thing about all this is that the valve is covered by a one-year warranty, but only if it was installed at a Denso or Toyota service center. I wonder what they will advise me.
The store`s offer stated that the valve fits the pump in my Ava, but maybe there is some nuance that I don`t know about. In appearance, the valve is perfectly the same as the old one, but maybe it`s just an apparent similarity. Maybe some other codes for this part are important
Does anyone know anything about this? Please help!

Added after 3 [hours] 10 [minutes]:

The situation seems to have cleared up. I installed the new valve again and this time I pumped the fuel thoroughly using a hand pump on the fuel filter, which I had not done before. The engine started working almost from the first tick. Now it starts every time. I`ll wait until tomorrow and see what happens when the engine is cold. I`m also curious why the old valve (after cleaning) started it without adding fuel with a hand pump. To summarize - I think I made a mistake in not using the pump and therefore not bleeding the fuel system. We will see.

Everything`s OK for now. Avka starts in the morning without any problems, but does this mean the end of the problems...? You have to wait for frost...

At Avensis we replaced these valves. We gave them a used one and they`ve been working fine for a year and a half now. Cost PLN 250 for stimulants with replacement.

It`s the same with my AVENSIS (2007, 90 KW, AD engine), it starts and stops at slight frosts, but at higher temperatures it cannot start at all.
Today it was -2 and the symptom has already appeared. It started and went out after 0.5 seconds, gave it some gas and it worked the second time, but if it gets to -10 it won`t be as nice.
Since last winter the car has been working perfectly, maybe a slight heaving when the revs are cold, but that`s very rare.

"memexmemex" tell me what the situation is like, I`m very curious what your results are!!!

mjaworsk wrote:

"memexmemex" tell me what the situation is like, I`m very curious what your results are!!!

I don`t want to "jinx it", but after replacing the SCV valve, everything is OK for now. Avka starts from the first tick and immediately revs - without any initial "hesitation". This wasn`t the case before - unless it was after another cleaning and starting the valve. I realize that a fully positive (I hope) diagnosis requires really severe frosts. Only then will I possibly celebrate the "victory". May...
In any case, I am 99% sure that your and my symptoms are caused by this unfortunate valve. When I was at the Toyota service center a year ago, they also told me this blindly, although of course I didn`t suggest anything to them. Moreover, this is proven by the fact that a few weeks ago when the car did not want to start at all (i.e. it started and immediately turned off), removing the valve and cleaning it in kerosene immediately helped. That`s why I decided to buy a new one. I suppose you could go to Diesel Systems in WA, leave the car overnight and suggest they hook it up to the tester in the morning with the engine cold. This is what I was offered to the Toyota service center in Radom. However, you should be aware that the symptom may not occur that morning. This is such an annoying glitch, that`s why I played va bank for "only" PLN 730

Thanks for the comprehensive answer!!!
I also tried cleaning, but unfortunately it went the other way I have the impression that it is worse after cleaning, but that would also indicate a problem with the valve.
Basically, you convinced me I`m also going to take the risk, but only at the end of the week.
Let me know how things turn out, I think that not one person will be in a situation like us.
I will also write if something becomes clear.

Regards

Maybe it will be useful to someone. In the version with two valves, they can be disconnected individually. If they are functional, the engine should reach and maintain maximum speed without any problems at idle speed. If one of them is stuck, that valve will have problems achieving and maintaining equal revolutions. I tested it. In case of problems, there is no need to clean or replace both, and other causes of the problem can be ruled out or confirmed.

I`ll dust off the topic a bit, I`m about to replace the SCV valves with new ones, the car loses power, error P1228 on the computer, I`m replacing both of them at once, but does anyone know any recommendations for replacement, I read somewhere that you need to flush the pump with the valves removed, is it true?

Hello !! Reading old posts, Toyota counts so much because, apart from the valve, the controller software changes after modification!! for 1 AD engines, as for 1 CD engines, which is a completely different engine and fuel system, they sell SCV valves only as a set and here the fuel system is much worse, fuel pumps often come loose and injectors fail, where regeneration exceeds the price of the vehicle! If after replacing the valves it doesn`t help, I recommend taking the pump and the injectors out and checking them.

luki299 wrote:

and injectors fail, where regeneration exceeds the price of the vehicle! If after replacing the valves it doesn`t help, I recommend taking the pump and the injectors out and checking them.

If this happens to you, prepare PLN 6,000 for repairs, only then you can say that you will have peace of mind for 2 years.
The repair is much more expensive than in lagoons/Megans and Clijs.

In general, you really have to lose your mind to buy these pads with this engine.

Hello, after replacing the valves with a new one, the car starts right up and when maneuvering calmly, the check light keeps coming on and the car loses power and turns off after a while.

So initially the replacement did not help and PLN 800 went out of pocket.

Generally, after turning the ignition on, the car starts again and the problem disappears until the next quiet start, e.g. when you slowly drive over a threshold with 2, yak, or start at a lower speed... When driving vigorously, there is no problem...

Do you have any idea what to do next? Reloading, injectors, pump?

It seems to me that there may be a problem with a broken wire somewhere. At low revs the engine shakes and loses contact. Start it and move the beams, maybe something will show up.

Tomorrow I'll change the oil and all the filters, and I'll check the harnesses right away.

Basically, I connected the computer again and a new error appeared

78(7) fuel line malfunction


They write on the forum to fiddle with this fuel supply.