IS220d strange problem, possibly turbo?

[Shahpor]

Ok, I am a little confused.  These cars don't have variable vane turbos, so which vacuum valve were you looking at last night?

I have just gone out and had a look at mine, so here it is for comparison:

 

As you can see, yours appears right.

I could barely see the wastegate, let alone get to it, but does yours turn off and on from when you first start it, or does it need to get hot first?

Also, what I couldn't see was where the second metal pipe goes from the two heading down the left of the picture.  I am assuming one goes to the wastegate actuator, so I am wondering what the other one does.

[Ado1379]

I am definitely confused,

my understanding is the one on the right in the picture controls the wastegate. In that case I have got those pipes the wrong way round according to our pictures. 

I have the metal heat guard off so I can see the back off the turbo. 2 second I’ll go and take pictures...

[Ado1379]

There are 2 diaphragms with actuators down there. Both pipes leading to them. I am assuming one is the wastegate? So what’s the other 

[Shahpor]

I am going to have to investigate this further.

Firstly, you are right in that the valve on the right is also a vacuum valve.  The confusing thing is that the manual has two valves listed - a Vacuum Switching Valve and a Vacuum Regulating Valve.

The one on the right is the Vacuum Switching Valve.  Now, the manual states that this valve is for Emission Control, and it appears the IS250 also has one, so I am inclined the think the Vacuum Regulating Valve is the one that controls the turbo boost.

If so, then it is the one I posted about earlier.  Was this the one you run the tests on?

The manual does state there are two vacuum hoses back there, but it doesn't say what each is for.

I also have no clue what that second vacuum actuator on the right does.

[Ado1379]

Okay, so the mysterious valve on the right goes to the first actuator you can see in that picture (what I mistook for the wastegate) and this is the one that keeps opening and closing when the car fails, I have noticed it only fails when the car is up to temperature.

the valve on the left (the one I tested last night) does go to the wastegate. The wastegate opens and closes if you pinch the vacuum pipe and let it go so I’m sure that is working correctly 

[Shahpor]

Ok, just to be clear, This valve is the one you tested:

 

Which goes to the wastegate here:

 

Is that right?

[Ado1379]

Yes haha!

but I originally thought this was the wastegate. 

And this is the actuator that is stable until the car fails then it keeps opening and closing. So I’m trying to figure out what that actuator is? 

 

[Shahpor]

Ok, I have figured it out.

It is the EGR Cooler:

 

So, now it gets tricky.  Since you have had the EGR valve blanked off, what was done with this?

[Shahpor]

Also, since the turbo wastegate seems to be operating normally, the reason for the loss of power is still unexplained.

[Ado1379]

okay, nothing was done with this as far as I am aware, but seeing as though the EGR is blanked, I could disconnect this? 

It uses the same air feed as the wastegate vacuum valve. So maybe because this cooling actuator is constantly opening and closing it’s reducing the vacuum input (or lack of) on the wastegate? I maybe talking nonsense too 😂 

it also seems to start playing up when the engine is at operating temperature. Reading about these cooler egr coolers they only kick in at operating temperature? 

 

[Shahpor]

Well, that's the thing;  since you have modified your EGR system, we can't be sure how it has been set up to work.

Hang on, earlier you said you had checked the wastegate wasn't stuck.  Which actuator did you check?  Bear in mind everything we have discussed up until this point has assumed you are talking about the actuator on the bottom in the picture you posted.

At this point, I think you need a copy of the Techstream software to see what the car is doing while it is running.

Has it ever had the engine management light come on when this happens?

[Ado1379]

So it’s definately not the wastegate. It failed on me just then so while the engine was running, the actuator arm was down, I disconnected the vacuum and it shot straight up, I then connected it and it moved straight down again. So it can’t be stuck.

i think you’re right, I need the techsteam data 

[Ado1379]

never had an engine management light 

[Miłosz]

Low fuel preasure.

[Shahpor]

2 hours ago, Ado1379 said:

So it’s definately not the wastegate. It failed on me just then so while the engine was running, the actuator arm was down, I disconnected the vacuum and it shot straight up, I then connected it and it moved straight down again. So it can’t be stuck.

i think you’re right, I need the techsteam data 

 

I'm getting confused again.  What failed on you?  And which actuator moved when you disconnected the vacuum line?

 

[Ado1379]

7 minutes ago, Shahpor said:

 

I'm getting confused again.  What failed on you?  And which actuator moved when you disconnected the vacuum line?

 

The car failed on me as was getting fuel, the wastegate actuator was the one moving. 

 

18 minutes ago, Miłosz said:

Low fuel preasure.

I’m intrigued by this. Would I get any other symptoms? The car does take a good 3-4 seconds to start up when cold, then over revs for a few seconds before idling normally 

[Miłosz]

As i said, scv. Toyota/lexus diag system is like commodore, without live data reading only dtc its not a diagnose. I checked my on dyno run, but you can check your on road during driving.

EDIT :

I have something like that when i I was accelerating at around 3000 rpm power fall, sometimes accelerated without problmes , but the problem was more and more frequent.

[Ado1379]

Well if anything it’s a new avenue to go down.

when the car loses power it won’t even rev above 3000 RPM! 

Where can I find the SCV on this car or is this where I have to take it to a mechanic...

[Miłosz]

scv is on the back on engine in supply pump

[Miłosz]

But firstly read all data by commodore techstream : idling and 3000 rpm. And during accelerating.

[Shahpor]

Yep, I still think the TechStream software would be useful.

If you want to check the SCV, then you can do the following:

[Miłosz]

I think best way to check is live data. Inside scv you have only this piston which could work irregularly.

 

 

Cheapest way for checkig fuel preasure is elm e327 and apk ELMscan toyota.

 

[Ado1379]

Thanks guys, should keep me busy for a bit. I have the techstream in order I’m just waiting for it to turn up. 

I’ll keep you updated 

[Bigchad]

Just for info Shahpor the car defo has a variable vane turbo I presently have one sitting in my kitchen having been rebuilt yesterday,,the large actuator operates the vanes the one sitting at 45 degrees is the wastegate.

[Shahpor]

Really?  Don't suppose you can post a photo of what it looks like?

Also, do you know the make and model?

Thanks.