When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Did you get any Symptoms?
Carbon build up in direct injection engines are pretty common, Is that the intake ports for a Lexus DS4 dual injection engine? Is so, it should look much cleaner than that.
I do not think the picture you show is NX engine head, isn't it?
NX fuel delivery is with dual injection: direct in cylinders and secondary via intake manifold. Secondary injectors suppose to help washing off oil of intake valves. It would be interesting to see NX engine with 60K on it.
I do not think the picture you show is NX engine head, isn't it?
NX fuel delivery is with dual injection: direct in cylinders and secondary via intake manifold. Secondary injectors suppose to help washing off oil of intake valves. It would be interesting to see NX engine with 60K on it.
Someone posted, in another sub forum here, two 8AR-FTSs brought into a Lexus dealer and pulled out of cars due to warranty claims of misfire codes at around 60k miles. I think these pics are from that thread. Yes there's dual port and direct fuel injection but it doesn't eliminate the problem, only mitigates it.
The IS engines were redone because of this issue. I had problems with it until the day I got rid of it at 9 years and 125k miles, but it never stranded me. Only stuttered like it was going to break down because the computer would shut off a valve.
This is blunt CGI fake! When I started similar chat when I owned GDI NX, pundits here scolded me that surely Toyota engine with dual injectors can NOT possibly have carbon build up of this nature!!
here are some pictures of a Nx300 turbo 4 with 60K on it. Looks like a fair amount of carbon buildup on the intake ports. Anybody concerned?
Symptoms of carbon buildup
-rougher idle over time
-decreased power and efficiency
-rougher acceleracceleration
-more lag at lower rpm
How to mitigate the issue (without taking apart engine and cleaning intake ports)
Use thicker oil
change oil more often
Do full throttle acceleration once per week
Use fuel system cleaner
if I posted pics of something I would want references and a link/writeup... but since you posted some nasty/dirty pics I will just say hope thats not avg case. when I changed plugs at 40k looked ok.
Did you get any Symptoms?
Carbon build up in direct injection engines are pretty common, Is that the intake ports for a Lexus DS4 dual injection engine? Is so, it should look much cleaner than that.
This is not my engine.
Originally Posted by Lex2000TL
I do not think the picture you show is NX engine head, isn't it?
NX fuel delivery is with dual injection: direct in cylinders and secondary via intake manifold. Secondary injectors suppose to help washing off oil of intake valves. It would be interesting to see NX engine with 60K on it.
Yes, this is a NX300 engine (8AR-FTS) and yes, it does have 60k on it.
Originally Posted by chuyrobles
Add an oil catch can. I have and recommend Saikou Michi. Made in USA and excellent quality.
Oil catch cans area great idea, but you can simply mitigate the blow-by if you use 5w30 or 5w40 oil. The catch can will be nearly empty.
Originally Posted by is250gurl
The IS engines were redone because of this issue. I had problems with it until the day I got rid of it at 9 years and 125k miles, but it never stranded me. Only stuttered like it was going to break down because the computer would shut off a valve.
That stuttering has nothing to do with carbon buildup. sounds more like a bad ignition coil or maybe a fuel injector issue.
Originally Posted by ukrkoz
No, no, no
This is blunt CGI fake! When I started similar chat when I owned GDI NX, pundits here scolded me that surely Toyota engine with dual injectors can NOT possibly have carbon build up of this nature!!
Or, can it?
in worst case scenario driving conditions, such as frequent cold starts, short distance driving, lack of higher RPM acceleration, city driving, and using 0w20 it is totally possible.
Originally Posted by Torii
if I posted pics of something I would want references and a link/writeup... but since you posted some nasty/dirty pics I will just say hope thats not avg case. when I changed plugs at 40k looked ok.
I hope so too, but with 0w20 oil it's inevitable. I am trying to find the link where I found the pictures from. It was from this same forum, actually.
-Use 5w40 oil
-use fuel system cleaner every 30k miles
-get out onto the highway with a fully warm engine and give her a good 2-3 full throttle pulls to near redline
what do u all recommend for a fuel system cleaner?
Merry Christmas to all as well!
Redline SL-1 is very good. Alternatively, you can use Chevron Techron.
Run your tank ALL THE WAY to empty, as far as you can safely go without running out of fuel, add maybe half a bottle of the fuel cleaner, and then refuel no more than a quarter tank of fuel. Use Shell 91 because it has good additives. You want a strong concentration of fuel system cleaner.
Then, once the engine is fully warmed up, take her out on a safe open road and give it a couple full throttle runs (do 3 pulls close to redline @ full throttle, carefully rolling onto the throttle as the RPM's increase, shift 500-1000RPM before redline)
It does not sound like this is a wide spread problem with the NX. I am sure there are a few outliners out there with carbon build up problems but overall, the NX does not have a wide spread carbon build up problem. Those pics might be from a modified engine that might be running too rich or the owner might be using a low octane gas.
12-15-19, 08:39 PM
Carbon Build-Up on Intake Valves... 60,000Miles+
