IS250 Just cleaned my MAF Sensor

[AntC]

So the rattle has been back for some time now even though I haven't reached 5k miles since my last oil change. Oil level also appears to be at max from what I can tell, considering how the IS2 dipstick likes to smear everything.

I'm wondering whether to change the VVT oil control solenoids, however, there's two of them and they aren't very cheap either. Not to mention that doing so may not resolve the issue as well.

I'm also considering an engine flush, though I haven't done one before on any car. Any tips on how/if the flush should be done? I have seen other threads regarding the rattle mentioning that it goes away after an engine flush, and the fact that it was gone for some time after changing my oil gives me some hope. Though I am somewhat skeptical, since I've heard that doing a flush can release all kind of gunk from the engine and cause issues depending on the build-up. I assume there's no way to tell without taking the entire engine apart which I don't plan on doing.

Would appreciate any advice that can help in getting rid of this horrible noise.

Cheers

[Mr Vlad]

That's a shame Ant. As for flushing. There's always pros and cons to flushing. Up until I started using dealers to service my cars I religiously used a flushing agent in my cars. I did oil changes at 5k intervals. I drove my cars hard. I assume you like to floor your V6 and I don't blame you, I do to regularly lol. I wouldn't worry that using a flush will release gunk and block an oil way. It won't because you've changed your oil regularly and drove your car 'perfectly '. I'm gobsmacked in this day and age of Internet shopping that you can't get ZX1. Have you tried amazon for example? Do you gave a friend abroad who could get it and send it on to you?

[AntC]

I do indeed like to floor it on a regular basis 😁 I've also done oil changes at 5k miles since I bought the car almost two years ago. However, as I mentioned, I have never done a flush on any car that I've owned so far.

Ordering a bottle of ZX1 shouldn't be an issue, even tough it will likely come at triple price with delivery, import tax, and VAT. Though I wasn't able to find the engine flush specifically on either eBay or amazon. I'm only seeing a ZX1 oil additive, and no flush.

I may check out some reviews and order a different brand. Just to double-check, when flushing the engine, it should also be rinced with some cheap oil and a cheap filter before using the actual oil correct?

Also, has anyone tried changing the left and right VVTi solenoids in regards to this issue? I saw a comment on a Youtube video saying this has resolved it, but the solenoids are quite expensive.

[chr15gb]

5 hours ago, AntC said:

Also, has anyone tried changing the left and right VVTi solenoids in regards to this issue? I saw a comment on a Youtube video saying this has resolved it, but the solenoids are quite expensive.

I used my Techstream on a mates Yaris to prove the VVT were functional but they are easy to remove and plenty of videos explaining how to test them without firing the parts cannon at it.

 

[AntC]

Thanks for the info. I'll try testing the solenoids and if they're not the issue I'll try an engine flush at the next oil change.

Will make sure to post updates.

Cheers

[Texas]

Have you checked these filters first?

 

[AntC]

I did replace both filters when I bought the car initially and have had them cleaned once since, however, that was like 3-4 oil changes ago. I should probably give them a clean during the next one.

I also checked all 4 solenoids yesterday and even managed to break one bolt (resolved after a couple of hours fortunately) and all of them are working fine. I only cleaned the two on the left side with MAF cleaner though since taking out the right ones required removing the intake manifold. I also topped up the oil as it was in the middle of the dipstick.

Will do some tests to see if the rattle is still there, though if it's not I wouldn't be sure whether its due to the two solenoids being cleaned or the oil top up. Regardless, I'll post an update here when possible.

I also plan on flushing the engine and cleaning both filters during the next oil change. In fact, I might even do it sooner just to see if this will have any effect.

As the rattle did stop for some time after my last oil change, I'm thinking that the oil level being at maximum is what did it at the time, so I'm thinking I have to figure out how much oil is being burned so I can keep it at the max, though it is kind of difficult since I can rarely park on a completely even surface to do a proper check.

Thanks for all the help everyone! I'll make sure to post updates and any additional information on how to get rid of the nasty rattle is greatly appreciated!

 

[Texas]

I live on a slope also and have to check my oil level when I go to a fuel station and car is dead level.

note: I check it After I have filled and paid so it gives time for oil to settle, can’t say I have ever seen anyone else open their bonnet in a fuel station for years! I expect plenty would not even know how too🙄open the bonnet that is, let alone check the engine oil level!

[AntC]

Well, rattle is still there after cleaning both left solenoids and oil top up. Will post more updates after engine flush and cleaning both VVTi filters.

[AntC]

I did an engine flush yesterday using a Liqui Molly additive, then rinsed with cheap oil and filter and the oil did come out black so the engine flush did indeed clean something.

However, the annoying rattle is still here and driving me nuts.

Any ideas on what else I can check? Replacing the entire vvti mechanism is really out of the question for me since it will most likely cost a few thousand and is not worth it.

Strange thing is that the rattle was gone for some time after the previous oil change, but now its here even though I only had ~2500 miles with the old one.

[AntC]

An update. I checked the oil level a few times and its at max. After the flush the oil is so clear you can put it on your salad. But rattle is still there unfortunately. The only thing I can think of is cleaning the vvti filters. Will post another update when I get the chance to do so. Will appreciate any ideas in the meantime.

[J Henderson]

I don't think I've heard this rattle myself, and I've never used this product, but I've seen it being mentioned by US owners as a potential cure.

[Beamish]

I have used the following product in an IS250 in the past with great success  -  would be worth a try.

https://www.wynns.uk.com/product/hydraulic-valve-lifter-concentrate/

[AntC]

Another update. I went to the garage to have my front anti roll bar bushings replaced and had the guys check the VVTi filters. Both of them were clean but they cleaned them up anyway. Seems this is a result of the engine flush, since the oil still looks brand new a couple of thousand km later. Rattle is still there, however.

I just ordered a can of Wynn's hydraulic valve lifter to see if it will make a difference.

Does anyone know if it's ok to pour an additional 300ml of liquid, considering that the engine oil level is currently at max? Or should I wait for the car to burn some oil and add it then?

 

[Texas]

I can’t see 300ml of oil making that much difference in a V6.

[AntC]

Thanks for the info. I guess it's going to arrive tomorrow and I'll post an update in a week or so on whether it has had any effect.

[AntC]

So I've been driving with the oil additive for a couple of days now and still no effect. To my understanding, the hydraulic valve lifter does require some mileage to work. It's already in the engine oil anyway, so it's gonna stay there until the next oil change.

What I find most puzzling about this is that the rattle was not present when I got the car. It either developed when I bought it, or the previous owner was doing something different. So far, I've been using 5w30 oil only. Would it be worth a shot to use thinner oil? The idea being that thinner oil will flow through oil channels more easily and allow oil pressure to build up during the initial crank. Thus, by the time the engine starts, oil pressure would have locked the VVTi mechanism...in theory. Any suggestions on what oil viscosity I should try? The temperatures here can range from -10C in winter to 37-38C in the summer.

Cheers 

[J Henderson]

Perhaps give 0w30 oil a try. This is what the Lexus dealer always filled my car with, when it was still being serviced there.

It falls between the 2 grades that are recommended for an IS.

2005-2010 - 5w30

2011+ - 0w20

[Tyre Tread]

I used to get the rattle on start-up if I parked the car "nose down " on my sloping driveway so I started always back in and park "nose up" and never had the issue since.

 

[ahmed-abrar]

7 hours ago, Tyre Tread said:

I used to get the rattle on start-up if I parked the car "nose down " on my sloping driveway so I started always back in and park "nose up" and never had the issue since.

 

i have noticed this also recently on my car, i have checked my cars oil level & its perfectly correct

[AntC]

I may give 0w20 a try on my next oil change. 

Also, I too sometimes park the car nose down, however, the rattle happens on even surfaces as well. I guess parking it nose up may force the oil into place and reduce the rattle.

[H3XME]

On 8/1/2022 at 9:23 AM, AntC said:

I may give 0w20 a try on my next oil change. 

Also, I too sometimes park the car nose down, however, the rattle happens on even surfaces as well. I guess parking it nose up may force the oil into place and reduce the rattle.

You shouldn't go down to 0W20 if your car ran 5w30 all its life. There will be tolerances from the heavier oil, which increases the chances of it leaking into places it shouldn't.