Fuel level sender question - Emissions Control
Thread Starter
Teching In
Joined: May 2016
Posts: 25
Likes: 0
From: Sierra Madre, CA
Update: Success! Finally got the evap monitor to fire! Kudos to Eric (69 Ghost), he got me going in the right direction. Long story short, the fuel tank calibration was way off. I bought HPtuners so I could do some diagnostics and re-calibrate the fuel tank sensor. It was pretty easy to correct the table that related the sensor voltage to number of gallons remaining.
I also had to fix a P0446 code, it turned out that the oem Toyota hard line that I re-used from the original evap system was blocked. I just bypassed it and ran a 5/8" heater hose directly from the charcoal canister to the vent valve, which I relocated to the engine bay. HPtuners was very helpful to troubleshoot that problem. I also learned from monitoring that it takes about 5-6 cold starts for the evap to fire. Every day this week I let the car warm up for 3-4 minutes then drive off. Within a minute or two the PCM would command the vent valve open. Seems like that was the only consistent way to get the PCM to open the vent valve on its own, but I could be wrong.
I also had to fix a P0446 code, it turned out that the oem Toyota hard line that I re-used from the original evap system was blocked. I just bypassed it and ran a 5/8" heater hose directly from the charcoal canister to the vent valve, which I relocated to the engine bay. HPtuners was very helpful to troubleshoot that problem. I also learned from monitoring that it takes about 5-6 cold starts for the evap to fire. Every day this week I let the car warm up for 3-4 minutes then drive off. Within a minute or two the PCM would command the vent valve open. Seems like that was the only consistent way to get the PCM to open the vent valve on its own, but I could be wrong.
TECH Enthusiast
Joined: Feb 2008
Posts: 503
Likes: 1
From: Ventura, Ca
Here is one of the better articles on how to test for P0446.
https://aviondemand.com/insider/pull...of-code-p0446/
https://aviondemand.com/insider/pull...of-code-p0446/
