Charcoal canister purge and cold engine?

[Eicca]

The charcoal canister on the 100 starts putting off some nasty smells after driving at high rpms for a while (climbing hills, highway cruising, etc).

The VSVs both respond when tested with techstream.

I know it’s possible that the VSVs fail when hot, and seem normal when tested cold. I have leads on parts to replace them.

One last thing I want to confirm, before I order parts: is the charcoal canister purge programmed to happen only when the engine is hot?

I ask because the thermostat is stuck open. Takes forever to warm up. Fan hasn’t come on in a long time. After a nice long hill climb, coolant temp was 168F and it runs around 140F tops around town. So obviously I’ll be replacing that.

But, if the computer is programmed to wait until full operating temperature to purge the canister, that would be really nice and save me from ordering VSVs.

Hopefully someone knows the answer to this one.

Thanks in advance.

 

[2001LC]

First thing is to get your operating temp to normal.

A low coolant level can give a false low temp reading. What happens is water temp sensor is reading air, which is not near as hot as engine coolant. In this case you could actually be overheating. This is the Achilles heel of the 2UZ engine, that can kill the engine.

So first check coolant level:
Check coolant after 8 or more hour cool down (5 hour in very cold weather will due). Vehicle should be level, even better is if front end elevated. Look in radiator, level should be to very top under cap. Reservoir should be above low line..

If coolant level is topped and temp still low, replace thermostat. Good idea to to replace radiator cap at same time. Burp air from system by checking level after each cool down and top. Keep checking/topping daily until system will not except more coolant.

Few reasons that come to mind for running cool.
1. False temp reading. (covered above)
2. Weak thermostat. Cap may have minor effect here.
3. Bad water pump, which will leak 9 out of 10 times. (check front weep hole)
4. Very rich fuel mixture.

 

[Eicca]

Coolant level is fine. Radiator and cap are new, I did this myself over the summer. Water pump was changed a few years ago. Thermostat has never been touched as far as I know.

I started noticing the low operating temp and the funny evap smell issues around the same time.

 

[keep4word]

This May help.. From an old thread

 

[Eicca]

This May help.. From an old thread
View attachment 1868467

I think that’s for a 1FZ. The 2UZ canister is totally different. Lots more complex.

 

[TheForger]

Here is a similar cleaning process for an '04 LC

 

[Eicca]

Here is a similar cleaning process for an '04 LC

View attachment 1868541

View attachment 1868540

Appreciate it again but our 99 has the canister in the engine bay. Way different. I’ll hit google and see if I can find the procedure for mine.

 

[FLWookie]

How hard would it be to bypass this system for those of us that live in non-smog inspection states?
What causes the ECU to throw a code for the system?

 

[Eicca]

How hard would it be to bypass this system for those of us that live in non-smog inspection states?
What causes the ECU to throw a code for the system?

It looks like a pretty complex system. Lots of variables and sensors that would be hard to fudge.