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EVAP Removal: How to properly disable in the tune! IMPORTANT!

38K views 26 replies 14 participants last post by  AMD[H]unter  
#1 · (Edited by Moderator)
***VERY IMPORTANT!!!***

If anyone removes their EVAP system, it is imperative that it is disabled properly in the tune. Many tuners do not realize that if you just shut off the DTCs and/or canister switches the pcm will skip an entire section of code, thus allowing for the pcm to NOT adapt fuel whatsoever. As one exampe, during CL (Closed Loop) operation the pcm will not make fuel corrections based on the fuel trim data.

I have listed below the various parameters to disable in order to prevent any DTCs, as well as prevent the failure mode from occuring.

Canister Vent Solenoid Threshold for P1451 - Set to 255
Canister Vent Threshold for P1451 - Set to 63.990
Tank Pressure Transducer High Error - Set to 63.990
Threshold for P0443 Code - Set to 63.990

Within SCT Advantage 3 software, all 4 of these parameters are located in the "OBDII, Canister Purge, Scalar" section. If you do not see this sub-group of parameters, then you may need to update your software. With that being said, if you are on the latest update, and you still can't see these, that doesn't mean they aren't there, but rather that your software access is not keyed high enough. Even without key access to view them, you can use this value file located here to modify the above changes automatically:

(See this post for the value file: http://www.modularfords.com/threads...P-Removal-How-to-properly-disable-in-the-tune!-IMPORTANT!?p=1844153#post1844153 )

This particular value file will definitely work in the Terminators, Mach 1s, '02-'04 Lightnings, and some of the latter model year EEC-V based Mustang GTs. However, the "Canister Vent Solenoid Threshold for P1451" parameter is missing from some of the other SCT Ford templates for the various vehicle boxcodes. I will have to talk with Jerry about adding it in on the others. BTW, you can thank Jerry for all this data in this post, as he is the one who researched this for me.

If you're using Advantage 2, you're out of luck, and you will need to have your tune updated via a tuner using Advantage 3, and then have it converted from the 3 format (mtf) to 2 (csv).

Regards,

James
 
#3 ·
James, can I use this even if I haven't COMPLETELY removed my EVAP system?

I have a Cobra tank/pump, and I was unable to install one vent hose from the tank to the vent line going to the front of the car. This is due to having a GT with Cobra evap lines on the tank, the GT exhaust is in the way, so I just capped the lines... I'm not getting any codes, just wanted to make sure it wasn't hurting anything...

Thanks! :beer:
 
#4 ·
Sure, absolutely you can! However, as some word of advice, you need to make absolutely sure you have a functioning vent system on your tank, otherwise dangerous pressure could build up.

As an update to my original post above, this particular value file will definitely work in basically any EEC-V vehicle with these parameters. However, the "Canister Vent Solenoid Threshold for P1451" parameter (listed 1st in my list above) is actually not in some of the earlier years calibrations (it's not an SCT thing, but actually Ford just not having that parameter in some of them). That's fine, so just change the rest of them.

Regards,

James
 
#7 ·
the vent is there to allow it to suck air in 99% of the time. the only time it blows vapors out is when you are filling up at the pump. and i suppose on a hot day with the car in the sun.

as the fuel draws down in the tank, that empty space where the fuel was, it gets replaced with air. that air has to be able to get in from somewhere.

the easy answer is to use a vented gas cap but i dont know if they make any to fit the modern threads of our filler neck. i suppose you could poke a hole in it...
 
#15 ·
if anyone has removed their evap equipment, I need a part. It's the white plastic elbow that comes out of the bottom port of the evap canister and connects to a special fitting for a hose that i believe runs to the front of the car.
 
#17 ·
Thanks Rick! I'm going to have to make a thread about your generosity when I have time.
 
#19 ·
Mods and OP, if you're looking. The link is dead, the file is not attached, and the parameters specified are not available even in advantage 3.0 to a PRP.

How does one go about properly disabling evap?
 
#21 ·
Without getting into the discussion of why it is no longer available in SCT's software, here is a value file I created long ago that will take care of everything when removing EVAP. If you have a PRP, unzip this file, then go to File, Load All Values, and select the attached file. You will not see the changes, but it will eliminate the EVAP stuff correctly.
 

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