15,000 mile/throttle plate cleaning recommendation

[wfo9]

Interesting. This will reveal my ignorance of engine workings, but do these two statements mean that the PCV is routed such that it is upstream of the AF?

No, changing the air filter has nothing to do with the throttle body/plate being dirty.

It is 100% caused by the PCV system recirculating oily crankcase gasses into the intake (some also reverses into the fresh air source at WOT). The oil cooks/ on the base of the throttle body and block airflow. The ECU makes up for it with the idle air control learning, but it eventually maxes out and causes a problem.. It also may have a very slight impact on performance, but doubtful.

If you clean it every year or so, it will never cause a problem. Takes about 10 min to wipe it out.

I don't think the recommendation to clean it every 15k is really that bad. I do think charging $65 to do it is borderline criminal. It's slightly more effort than checking the oil level... and about equal to changing the air filter. If it does coke up completely, it will need to be removed and cleaned in a different way. That type of cleaning may be worth $65, but no way that is needed at 15k.

 

[Lester Lugnut]

"Mama's don't let your babies grow up to be cowboys.....let 'em be doctors and lawyers and Toyota Dealership Service Writers".

 

[philsey]

.. our toyota advisors in the top tier make about 110-140k....

Adam, I'm finding this really hard to believe. Do you know this for fact, and not 'someone said' ?

The reason I'm skeptical, is I cannot imagine that an owner would actually pay (even on commission) that much for that position.

 

[adam2562]

Adam, I'm finding this really hard to believe. Do you know this for fact, and not 'someone said' ?

The reason I'm skeptical, is I cannot imagine that an owner would actually pay (even on commission) that much for that position.

from the persons mouth yes, unless they both lied to me.. they were 10k off what each other made.

 

[adam2562]

don't get me wrong... writers at other dealerships in the area arent making close to that unless they're at bmw, mercedes, etc and still probably on their top guys make that. you have to remember.. this is the dc area which is wealthy and they have to compete.. a writer in NC isn't gonna make as much..

 

[Jeff614]

So are most of you who do your own maintenance doing this every 15k? 30k? Or more miles? Swear I haven't seen this in the maintenance part of the manual but will look again tomorrow. Will be hitting 30K miles probably come spring and wondering if I should add this to my other to-do items. Probably 75% highway driving, mpg stay pretty steady and throttle response seems same as when I bought it.

Just wondering, doesn't seem like a topic that comes with any frequency.

- Jeff

 

[BlackWorksInc]

No, changing the air filter has nothing to do with the throttle body/plate being dirty.

It is 100% caused by the PCV system recirculating oily crankcase gasses into the intake (some also reverses into the fresh air source at WOT). The oil cooks/ on the base of the throttle body and block airflow. The ECU makes up for it with the idle air control learning, but it eventually maxes out and causes a problem.. It also may have a very slight impact on performance, but doubtful.

If you clean it every year or so, it will never cause a problem. Takes about 10 min to wipe it out.

I don't think the recommendation to clean it every 15k is really that bad. I do think charging $65 to do it is borderline criminal. It's slightly more effort than checking the oil level... and about equal to changing the air filter. If it does coke up completely, it will need to be removed and cleaned in a different way. That type of cleaning may be worth $65, but no way that is needed at 15k.

Something else to keep in mind is that with VVTi and electronic throttles there is more back-flow from the valves as they can overlap longer than traditionally desired, not to mention the advents of PCV and EGR. In cases of shifting the ECM will command the throttle shut momentarily to "smooth" shifts out and such (faster than we would ever be able to do, but because of the fly by wire design the ECM can do things like that without the operator even knowing.) Though carbon/soot forming on the throttle blade is not as bad on most Toyota engines as it is say a GDI engine where the valve overlap and fuel manipulation is so great they choke themselves to death in carbon.

I believe 15k is a sort of unwritten industry standard recommendation now since many many engines do get dirty throttle blades and it doesn't hurt to prevent them from getting too bad.

That said, on a Toyota I really wouldn't get too bent out of shape on it. The 1GR-FE's are a little more of a pain to get to the throttle body than say my 2UZ-FE but no where near as much a pain in the ass as a 2AR-FE or 2AZ-FE.

If you have some time on your hands cleaning it out once a year or so won't be bad.