Hey everyone, any idea when Spring will finally arrive in Iowa?

Anyway.... 1999 four door four wheel drive 122k P0446 code. No other codes present. The rubber seal on the gas cap was cracked badly so thought I’d try a new cap. Code returned. Had an extra EVAP valve for above the spare tire, code returned. So, I broke out the FSM and the Tech2, finally found the EVAP seal function settings, hit enter on the Tech2 and the screen said it said fuel tank vacuum was too high, test aborted....

I tried the same thing on my 1998 just to make sure the Tech2 was working properly. It worked fine on this vehicle.

The gas cap was not difficult to remove on the 99, nor have I had any issues with putting fuel in it. So, I’m lost.....

Thoughts?

Thanks!
Chris

 

The fuel tank pressure sensor comes to my mind and you could carefully (with extreme care) x change the fuel tank pressure sensor from one of your rigs to the other...and then Tech 2 it...

 

I’ll see if I can get one off without breaking anything... worse case @122k it’s most likely due for a new fuel pump anyway. Last thing I need is for the kid to call and say it won’t start!!

Thanks

 

What was the tank pressure reading on the scanner? Did you try taking off the gas cap and checking the pressure again? If it doesn't read close to zero with the cap off, or it never changes, then you have a bad pressure sensor.

 

agree

 

The tech2 didn’t stay on the screen long enough to show me the readings, it almost immediately changed to the warning screen test cancelled... I did remove the gas cap and try again, same result. No luck removing the spare sensor from my parts truck so new Delphi fuel pump with new sensor from rock auto should be here today. Like I mentioned, with the mileage I may as well change the pump out if I’m under there messing around...

Thanks!

 

I've never used a Tech 2, but doesn't it have a data display mode where you can stream live data? That's where I'm talking about checking the pressure.

 

First one would have to find that setting!. -13.94 in H20 and 4.33 Volts.

 

Yup, it sounds like your sensor is, um, confused.

 

Thanks!!