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Roy W
12-28-2005, 17:57
I would like to experiment with disconnecting (unplugging) my EGR valve on my otherwise stock LLY. Can anyone give me some specifics or a picture as to where it is located on my 2005 model.

More Power
12-29-2005, 09:26
Can't just unplug it... It'll set EGR related trouble codes if you do.

There are ways to defeat EGR for off-road or race applications. :D www.kennedydiesel.com (http://www.kennedydiesel.com) offers products to do this.

Jim

Kennedy
12-29-2005, 09:50
If you unplug it, it will set codes. How it responds to these codes varies. Federal emissions trucks don't take any action, as they are considered "non emissions" codes. NE and CA trucks will typically set SES light and take action based on these codes.

96ccdd
12-29-2005, 14:19
Do a search on the web for "fingerstick". This is a product this splices into the wiring harness to full the EGR system you can also blank off the EGR.

What is a Finger Stick? It is a simple circuit that modifies the MAF signal on LLY engines (not LB7 engines) to expected levels when the EGR is blocked or a free flowing exhaust system causes the ECM to set codes. This will prevent a Service Engine Soon light from illuminating and will prevent the ECM from displaying DTC codes related to an EGR modification or larger exhaust.

There are other threads on this forum that cover this in much greater detail.

What follows are the connection instructions for the Fingers stick:

Everyone must be reminded that the D.P. member who provided this stick is providing it "as a generic circuit" and that you install it at your own risk. The manufacturer can not and will not be responsible for any damages, real or perceived, to you, your truck, or your marital life in whole or in part. Same goes for these installation directions. Read all these directions before installing. Ask questions first, install second.

You will only be cutting one wire! All others connections are simple taps of the wires.

Each wire's function is based on it's location on a connector. Make sure you follow the wires back from the MAF and EGR connectors. You never know when GM will change colors.

The first picture is of the Stick as shipped with each wire labeled as it will be used in the installation.

The second picture is of the EGR connector. The lowest passenger side wire on the connector is the EGR position sensor wire. On the example truck it is blue with a white stripe. The BLUE wire on the Stick should be tapped into this wire. Do NOT cut the original EGR wire!

The third picture is of the MAF sensor near the air filter.

The wire closest to the driver's side is the MAF signal wire. On the example truck it is yellow. This is the ONLY wire that should be cut. Splice the YELLOW wire on the Stick to the MAF sensor side of the cut wire and the YELLOW/GREEN to the harness side.

The next wire in is a ground and is gray on the example truck. The GRAY wire from the Stick gets tapped into this wire, Do not cut this wire!

The middle wire is the power wire and on the example truck it is pink. The RED wire on the Stick gets tapped into this wire. Do not cut this wire!

Installation Notes:

The EGR MUST be plugged in for the stick to operate properly.

It is much easier if you disconnect the air intake filter tube from the filter before you start. This will give you more room to work.

Wait until after you install your Stick, then clear all EGR DTC codes that may have been set, if desired, or 50 ignition cycles will eventually clear them.

Once the yellow wire in the engine harness is cut, the YELLOW wire of the stick will go towards the MAF wire on the air cleaner, letting the output of the stick (YELLOW/GREEN) go into the harness that goes across the engine.

For wire connections use wire taps, sometimes called splices. There are available at the local auto parts store. The wires on the harness and stick are thin, 22 gauge wires so make sure you get taps that handle the small wire. Soldering is even better.

For a clean install: Pull the plastic wire looms back far enough to make all the wire connections and splices easier, and don't put any wires back inside the looms until all the connections are finished. Then, when you're completely done, tuck everything back inside and finish with a little electrical tape to make the ends sanitary. For even a cleaner install, after plugging the EGR back in, you can put a piece of 1" wire loom from the MAF sensor down a foot to where the wires

Kennedy
12-29-2005, 15:28
Originally posted by 96ccdd:
Do a search on the web for "fingerstick". This is a product this splices into the wiring harness to full the EGR system you can also blank off the EGR.

That's kinda what MP was referring to. I call it my Blocker pkg as it does both.

For now though, he can experiment with how things act without altering any wiring.

Roy W
12-29-2005, 16:14
Okay.....I'm ready to try it.....Now where is the EGR valve plug ?????

Kennedy
12-30-2005, 07:03
The EGR connector is under the plastic air intake elbow. Basically, the connector faces forward and is in the cast iron part of the intake.

FYI, now that we have EFI Live (or the Diablo Predator), the diagnostic part of the EGR can be shut down without altering wiring. We will be offering exchange ECM service or tuning support to our EFI Live customers to do this. We do NOT disable the EGR, only the diagnostic. The end user must take the responsibility of the tampering.

20050518|4|000086|000000|68.226.176.104
01-04-2006, 11:05
Is there any performance/mileage boost associated with this modification?

Kennedy
01-04-2006, 19:19
Some feel that response and mpg improves. I couldn't say for sure as mine ceased to function the day that I took delivery. No soot in my intake...