TRD/ Magnuson 4.0 Supercharger Tips, Tricks, and Mods

Alright guys. Never ending drama here with this rich at initial fill ups issue..

Something has to be causing my charcoal canister to get saturated with fuel when I fill up which apparently as a byproduct is causing the purge valve to open up to release excessive fuel vapors.

- Purge valve is ruled out as good now
- As a side note I have filled up with the car running in the past, when I have, I have noticed my AFR gauge starts to go rich. Since the car is running thi condition corrects itself fairly quickly.

Either the fuel pressure regulator on the fuel pump bucket assembly is bad or I have a bad canister assembly... something tells me there is some sort of valve or stop or something which keeps the fuel from not going past a certain level is defective.

I have checked all data and as usual Toyota provides the worst information which also happens to be incredibly buried and difficult to find even for something as simple as component diagrams.

Keep the ideas coming... it would be much welcomed.

 

Ask @Skootter14. I believe he changed out his canister. He might have info on symptoms before he did. Also, why do you fuel up while running? I was told that's a no no unless it's a diesel.

 

Probably from being at higher elevation 1500 F vs 800 ft.

 

I know he changed it out in the past, but he had evap codes. I do not, so I literally am diagnosing blind on this one. All I have determined up to this point is that excessive fuel vapors are causing the EVAP purge valve to hang open while at idle only after fill ups. So either there is something defective in the canister or the root of thi issue originates within the fuel tank.

I have filled up while running in the past for reasons. It doesn't affect a thing on a gas powered engine assuming everything is functioning correctly. In the tank/ evap system.

 

Have you seen this thread?
https://www.tacomaworld.com/threads/1gr-fes-fuel-injectors-discoveries.541430/

I’m not convinced your issues are related as yours is only happening at fuel up, but interesting read either way.

I have no clue on how all the evap system works so I am no help there

 

Could a breather vent connected to the tank be plugged?

 

Yes but remember those are greens not the yellows. I don't have nor have I ever had issues with fuel fouled smelling engine oil at the time of oil changes, let alone the dipstick. This is strictly a fill up only issue.

That would be vent valve related, which is typically a part sold with the canister assembly. As far as I know the canister assembly alone costs well over $500. I would also highly likely have a code tied to that issue.

If there was an issue venting fuel pressure it would typically show itself in a way that you would have difficulty introducing fuel into the fuel system. I would have to do a lot of click click click action at the pump when attempting to fill up. As always if there is anything I have learned in the last decade and a half of working on cars it's that everything you THINK you know turns out to be wrong when the part you swore could not be causing issues, indeed is.

Something tells me a valve or regulator of sorts is defective. As the issue began intermittently, and now it happens every single time I fill up. Then eventually clears itself out.

 

Understand. I really dont know much about this. Just learning and offering ideas that might spark an idea leading to a solution.

 

For every 1000 feet in elevation change, you should only lose 3% of your output. So that could account for another 10 g/s. Getting there. Still missing 25. Maybe the Donaldson is super dirty? Might swap the AFE in, just for kicks.

 

Don't forget the Gates Racing belt. 5 rib, but grips better. Been working flawlessly for @Lucario Runner and myself, for years.

 

I appreciate it man. Any help is always welcomed.

For anyone reading this, I should add as well that I remember one time like 2 or 3 years ago I went to fuel up at a gas station and remember filling up until the nozzle stopped, I went to pull out the nozzle and saw fuel at the top of the fuel filler neck. I remember it being really weird, dismissed it, then hopped in the truck to start it. The tank read 3/4 full instead of past F like it always fills up to. That was the only time the issue ever happened of course thinking about it in retrospect makes me pretty sure it is all related now.

 

Those belts do not exist under that name anymore, as their color and even their name has been relabeled to the RPM series, and they are usually black while sporting the words "RPM" on them. Same construction, different name and color now though.

 

For the main serpentine belt I presume?

 

Donaldson could be extremely dirty, also when I go through mud water and mud has splashed onto my filter because I do not have a wheel well liner anymore. Are you sure every 1000 ft is only 3%? It feels like more than that but I could be wrong. Also for all I know my belt could be slipping. Running original belt on the 2.85 pulley. Belt has over 25k on it.

 

Yeah, but the problem with those is that they DO NOT stretch. Like at all. if you are wrong in your sizing for one reason or another that belt will snap and will snap hard.

 

I was fortunate to have the 5 horseman codes of all evap codes that spell out canister.

It may not hurt to take the canister and hoses out though, check connections, make sure hoses are clear, connections secure. It’ll only cost you time. I’d start there and see if you find any abnormalities in that PITA system

EDIT: the only real “symptom” of my codes (aside from the UG codes) is decreased fuel economy. Hard to detect even with the UG as it’s appeared minimal in my case. That canister is there just bc of CA laws (haha just being facetious)

 

What i'm going to do is smoke test the entire evap system tomorrow. If there are no obvious leaks out of the canister area I'll have to start investigating deeper. There is definitely some sort of valve that is totally defective now as it manifests itself with no shame at every fill up now. Makes me want to burn this truck to the ground.

 

Def understandable man. Hopefully the test will determine a large leak in a hose fitting and a simple adjustment will fix the system.

 

I really hope so man. I have been dealing with this headache for too long now.

Toyota. Oh what a feeling. Yeah.. of anger.