HP Tuners Section C Disable the Exhaust Gas Recirculation (EGR) Codes (1999-2001 engines only)
Having disabled the Secondary O2 Sensor codes in Section A as well as the Evaporative Emission System (EVAP) Codes in Section B we move on to the EGR codes. This only applies to engines from 1999-2001 vehicles as the factory did away with EGR in 2002. We are doing a batch of codes at a time in this tutorial, but once you get through it once, you are welcome to disable all the necessary codes on your second LS Swap project all at once ha ha.
It's worth repeating there are two schools of thought when it comes to LS Swaps and disabling the codes, some say drive the truck and see what codes it throws than research them a bit and if applicable, delete them. Nothing wrong with that method, but since I like to prep my PCM ahead of time before the engine even swallows a drop of gasoline, and especially since I know exactly what was deleted after all I deleted it, we might as well prevent those Codes from popping up ahead of time. Also and this may tip the scales, if you do your diligence and disable all the codes the best you can for the components you deleted than your MIL should not come on. However if it does, you should turn off the engine and look up the code rather than ignoring it assuming, eh it's probably for one of the items I deleted, and blindly press on with a glaring MIL. Hope you followed that logic.
[Rant] I have always struggled with the concept of EGR, I mean I get what it's supposed to do (appease the Environmental Protection Agency), but here we are putting a fuel filter to clean our fuel, here we are putting an air filter to clean our air, and we are all sold on the idea of "cold air intake" so we build crazy air damn isolation contraptions for our intakes, and than we turn around and pump in the hottest, dirtiest of exhaust gases (I mean the gases that did not burn the first time around) into our intakes bypassing any and all filters. That's like hitting yourself in a head with a hammer cause it feels good when you stop, ha ha. I have seen people on forums actually claim how their cars run better cause of EGRs, um ok, well even the factory finally dropped the EGR scam in 2002 so there's that [/Rant]
Tunistas let's meet the seven EGR codes:
P0401 Exhaust Gas Recirculation Flow
P0402 Exhaust Gas Recirculation Flow Insufficient Detected
P0404 Exhaust Gas Recirculation Flow Excessive Detection
P0405 Exhaust Gas Recirculation Control Circuit Range/Performance
P1404 Exhaust Gas Recirculation (EGR) Closed Position Performance
P1406 EGR Valve Pintle Position Circuit
P1409 EGR Vacuum System Leak
Now let's look at the Black Magic that it takes to disable these codes, we have two controls:
If it was up to me I would break it up into a third control so it would look more like this:
- SES (Enable / Disable)
- MIL (MIL On First Error, MIL on Second Error, No MIL Light)
- Report Code (On / Off)
1. Again we start in the comfort of our own home, we fire up our laptop and launch the Editor. Open the file we saved in Step 3 of Section B. (Our last saved file is always our starting point).
2. Make changes in the Editor, this time we will make changes only to the Exhaust Gas Recirculation codes. Refer to the cheat sheet below and Disable the SES on these and set the MIL to No Error Reported:
P0401
P0402 - was already disabled on mine from the factory
P0404
P0405
P1404
P1406 - was already disabled on mine from the factory
P1409 - was already disabled on mine from the factory
3. Save the changes you made to a new file and call it something like "06 - Disabled O2s & EVAP & EGR"
4. Now you get to move the operation to your truck, hook up your HP Tuner to the OBDII port and then your USB cable to your laptop, turn the key to the ON position, launch the Editor program, and simply write the new changes to the PCM.
Note: sometimes you have to write the entire tune file to the PCM, sometimes it is perfectly happy with only writing what's changed, more on this later.
More words with each pic: