Hey guys! I’ve been trying to learn to do some basic DIY stuff...I was bored so I thought I’d clean my MAF sensor and throttle body.
I drive a 2015 350 AWD with 92,000 km...MAF seemed spotless so I removed it but didn’t want to spray it. Throttle body also looked weirdly clean but I still wanted to spray it, except I ran into an issue.. every source online said you shouldn’t force open the throttle body plate with ur fingers as it’s electric and has gears...ok, so they say you put the car ignition to ON and have someone push the gas and the plate will open allowing you to clean it..
problem is my plate wouldn’t open. I tried all ignition settings, I could not get the throttle body plate to open to clean around it.
I know most have never tried this but has anyone cleaned their own throttle body? How’d you get the plate to open?

 

I've cleaned the throttle body before and just pushed the plate open with my fingers, cleaned around it and let it close back one it's own.
Maybe there are some brands of cars out there that this would damage the throttle body, but haven't seen it happen on a Toyota yet.

Of course I'm slowly pushing the plate open as you can feel resistance from the mechanism, and I'm also not trying to force it beyond it's max opening.
When I'm actually cleaning it I'm fairly aggressive, so I think you'll be fine.

 

Have you cleaned the one on your IS before?
I just tried pushing it open with my fingers and it’s pretty friggin tough, I was pushing quite hard but it didn’t budge and I didn’t want to force it. I was hoping you could open it just by pushing the gas pedal while the car is on the “ignition on” setting. Do you know if the service manual states how you open it during cleaning?

 

Yes, I've done the one on my car.
If I recall correctly, you push on the bottom inwards, and the top opens towards you. Pushing on the top won't do anything as it doesn't open in that direction.
Most, if not all, Toyotas are like this. Sometimes the initial push takes a little effort depending how much carbon is built up...keeping in mind the carbon will be around the edge of the flap that you can't see...and on the back of the flap too.
You likely won't see much carbon on the front of the flap, so it may look like it's pretty clean...even when it isn't.
The repair manual doesn't provide instructions for cleaning it.

 

thanks for replying, will try again tonight. It appeared damn near spotless as I had it cleaned about 40,000km ago but maybe when I open I will see some gunk. What do you know about the pressurized fuel injector service Toyota/Lexus offer? I got it done for like $80 by an independent Toyota master tech in Markham about 45,000km ago, any benefit to having it done again or is that overkill?

 

I would say that every 2 years or 50,000kms to have the throttle body cleaned and fuel injector flush is good preventative maintenance.
Of course based on your driving habits you may want to do it sooner or later.
For instance if you drive a lot you may want to wait a little longer to do it.

 

have you or would you ever run Seafoam in a modern car like the 3is?

 

I haven't used Seafoam products...but they make a few different items.
They seem well regarded, so no harm if you use them as directed.
I use Shell Gold all the time and change my oil every 5K kms...so I haven't seen a need yet to use other products.
Doesn't mean the car wouldn't benefit from it, I just haven't found a reason yet. My car is over 7 years old and is almost at 79K kms.
I'll probably do the plugs soon, and will check the throttle body at that time for cleaning...I'm going to have it all apart anyways.

 

what oil do you use? I thought I was OCD for changing oil every 7000km with full synthetics but you do 5?
I notice at 7000km oil is jet black and my mechanic always comments on how bad the oil is. I buy a full synthetic when Canadian tire does their 50% off oil sales, all in I pay 70$ for an oil change with OEM filter, full synthetic and labor.
But I’m in Ottawa, I drive pretty quick & I make a ton of short trips. I did rear diff fluid today, first time in 40,000km last one was Toyota OEM gear fluid it was still brand new looking, I was shocked how clean it was. I’m doing front diff next week with serpentine belt. Lexus dealer wants $67 in labor and I’m buying the belt from the Toyota dealership for $57.

 

I get oil from Crappy Tire too...whenever it's on 50% off sale. So far it's been between Castrol Edge and Pennzoil 0W20.
I also use one of those hand pump units that sucks all the oil out through the dipstick tube.
It's true you still need to get under the car to change the filter, but the filter is at the front, so you're not under too far and the car doesn't need to be that high, plus it saves the mess of draining the oil into a bucket (splatter) and gets more oil out.

The oil will get black fairly quick for a couple reasons.
Chances are after an oil change the oil will be black by as soon as 3,000kms

 

Hey all,
Sorry to jump in, I have a question for you 'Lexperts' in regards to properly cleaning the Throttle Body and MAF Sensor on my 2015 IS 250 F Sport RWD (103k mi.)


I have the CRC Performance Pack that Im going to use to help with some performance issues as well as some routine maintenance. I've used the Intake Valve Cleaner before and it worked nicely (about 12k miles ago) - we just got back from a long cross country trip where she proved herself on the road. However shortly before arriving back, I started to notice issues commonly associated with Carbon Buildup. I know by the 3rd gen they got better but, there is still very much a Carbon Deposit issue to address with these engines. Im starting to redline more easy at slower speeds and I've now noticed on more rarer occasion while traveling at higher speeds, that the rev gets high for a few seconds but then in Sport Mode its almost red lining or sometimes just red lined after accelerating harder to pass. I end up messing with the gas pedal to stop it quickly.

I've also read else where on these various Lexus threads that people have had troubles specifically with the IS models and the cold. But id like some more clarification on people's experiences - I know TBs don't like the extreme cold for start ups of course... we spent nearly 2 months driving in a Minnesota winter after a So California/North Carolina summer and fall.

My biggest question is on the MAF sensor and cleaning it, specifically with the CRC MAF Sensor Cleaner.
Ive heard this about it before as well as it even says on the can itself, do not use with Karman-Vortex air flow sensors ex. Toyota Supra Turbos, Mitsubishi and most Lexus vehicles.

For some reason I cannot for the life of me find anything seeming like we shouldn't use the CRC MAF Cleaner in our cars, nor could I find the info on the MAF installed during its build.

What kind of MAF Sensor did Lexus use for my model - 2015 IS250 F Sport RWD
And if I cannot use this, I would appreciate any suggestions on how to proceed with the MAF Sensor being cleaned?

I am going to change the oil soon, but first
I intend to use the CRC GDI Intake Valve Cleaner before that and follow through with blowing out the build up.

For the CRC Throttle Body Cleaner/Cleaning the TB, does anyone have any knowledge/tips/advice.
I generally know how to clean a throttle body, and am assuming mine will be the same bit of resistance and method as the OG poster. Is there just anything special to pay attention to with our cars. And what results have you had with the CRC Brand if familar?

I have the Royal Purple Max Clean Fuel System Cleaner and Stabilizer as well as a Lucas Oil Deep System Clean Fuel Additive. Im going to use Royal Purple first i believe.

I still need my 100k service

I'm hoping that this will help eliminate the issues I mentioned earlier,

 

Just a couple comments on your post that may help.

The IS doesn't have a Karman-Vortex MAF...it's been almost three decades since Toyota has used that type of MAF and even then only a few cars had it like the Supra.
You can use the CRC cleaner as directed on the IS MAF.
I'm sure there is some fancy name for the MAF, but essentially it's a 'Hot-wire' type air flow sensor.

While it's true Toyota addressed the carbon buildup issue on the 3IS (even before the 2IS model ended), the reality is all engines will have carbon buildup, and engines with direct injection only will have that much more carbon buildup.
Carbon is just a byproduct of combustion, like anything else preventive maintenance will help keep it at bay.

I wasn't too clear on what issues you were referring to with the redline observations or the TB not liking cold startups.
On cold starts the ECM will open the TB appropriately to allow the vehicle to fast idle so it can warm up. Fast idle is really temperature dependent, so it could idle at 1200rpm or 2200rpm, really just depends how cold it is outside.
I don't see the observations about it shifting at or close to redline being any issue since the ECM will determine shift points based on accelerator position vs vehicle speed and other factors...maybe I'm missing something. And the shift patterns do change in Sport mode to be more aggressive.