2G MAF in a 1G TEL/GVR4

Here's a look at the 1G plug. It should be the same for 1G TELs and GVR4s, except for one wire (#1). Note the pic is looking at the terminal side of the plug (wires facing away from you) on the left and top right. However, you need to pay attention to the "Wire side" part of the diagram on the bottom right, since that is what you will be looking at as you cut the wires.

1G TEL
1 - GW	2 - GL	3 - R	4 - GR
5 - NONE	6 - GB	7 - GY	8 - GO

GVR4
1 - GY	2 - GL	3 - R	4 - GR
5 - NONE	6 - GB	7 - GY	8 - GO

NOTE that the GVR4 has two GY wires, so you need to be careful when connecting the wires - it is best to cut/splice them one at a time to make sure you have the right GY wire. It's not hard if you do them one at a time, as the 1GY wire is the top corner of the plug, the 7GY is not the bottom opposite corner, it is 1 wire in from the corner.

Now the hookup to the 2G plug - there are many ways you can do this, here are some of them,
listed from the least modifications to the car to the most:

• Make an adapter harness - get a spare 1G MAF from a junkyard, break the stock plug out of it, trim down the circuit board that the pins attach to (or cut the pins from the board), and solder the 2G MAF plug wires to the 1G MAF plug. This allows a pure plug-in solution and makes it a quick swap back to your 1G MAF if needed. If you do this, make sure to fill the space between the pins on the plug from the spare MAF with RTV, WindoWeld, or epoxy (you can wrap tape around the entire plug, fill with epoxy, then remove the tape after the epoxy has dried) so that the pins/wires can't touch if the adapter harness gets beat around. Make sure to test the adapter harness on the car before filling in the plug.
• Strip the insulation back on the stock wires, solder the 2G wires to them, and tape the joints
• Do the same as above, but remove the terminals from the 1G plug one at a time and use heatshrink tubing instead of electrical tape, then put the terminals back into the 1G plug
• Cut the 1G MAF plug off (remember, one wire at a time!) attach the wires to a terminal strip or Molex plug, and attach the 2G wires to the terminal strip or mating Molex plug (this allows you to Molex the stock 1G plug to enable switching back and forth if needed).
• Cut the 1G MAF plug off (remember, one wire at a time!) and solder the 2G wires directly to the car's wires.

FYI: you don't have to track down a 2G MAF plug.
The ignitor plug on 91-up (or 92-up?) DSMs is the same configuration, though you'll need to pull one of the wires and move it so that it matches up with the MAF. To swap the wire:

• Depress the tabs on the one end of the tan wire retainer and push/pull it out of the plug
• Grab the orange silicone plug in position 5 and pull it out
• Shine a flashlight in the back of the plug, you will see a tab holding the number 8 terminal in the plug
• Stick a pin/needle in there and depress the tab and the wire pulls out easily. Do not just yank on the wire!
• Place that wire in position 5, place the orange silicone plug in position 8, and replace the tan wire retainer in the plug

Here are the wire colors for the 2G MAF, late 1G transistor plug, and 2G transistor plug. For the transistor plugs, the first row is the stock wiring configuration, the second is after you have moved the wire in position 8 to position 5. Pictured is an empty plug, and a late 1G Transistor plug.

2G MAF Plug wiring	1 - GY	2 - O	3 - LY	4 - R	5 - B	6 - RL	7 - RW	8 - None
Stock late 1G Power Transistor Plug wiring	1 - YB	2 - YR	3 - B	4 - W	5 - None	6 - BW	7 - Y	8 - YG
Modified Power Transistor Plug wiring	1 - YB	2 - YR	3 - B	4 - W	5 - YG	6 - BW	7 - Y	8 - None
Stock 2G Power Transistor Plug wiring	1 - LB	2 - BrR	3 - B	4 - W	5 - None	6 - BW	7 - BL	8 - BW
Modified 2G Power Transistor Plug wiring	1 - LB	2 - BrR	3 - B	4 - W	5 - BW	6 - BW	7 - BL	8 - None
"Mystery" Plug wiring	1 - GR	2 - P	3 - WB	4 - R	5 - B	6 - RB	7 - L	8 - None
TEL wiring	4 - GR	7 - GY	2 - GL	3 - R	6 - GB	8 - GO	1 - GW	NA
GVR4 wiring	4 - GR	7 - GY	2 - GL	3 - R	6 - GB	8 - GO	1 - GY	NA
Remember not to mix up the 2 GY wires on the GVR4!

So what do all those letters mean? Here's the factory wire color table:

Code	Color		Code	Color		Code	Color		Code	Color		Code	Color
B	Black		Br	Brown		G	Green		Gr	Grey		L	Blue
Lg	Lt green		O	Orange		P	Pink		R	Red		Sb	Lt blue
V	Violet		W	White		Y	Yellow

Here's a pic of an adapter harness I've made for one of my cars. I got a dead 1G MAF and broke the plug out of it and soldered the late 1G Transistor Power plug wires directly to the 1G MAF terminals. Once it is tested and working, I'm going to fill the solder joint area with WindoWeld. This adapter will let me easily plug the 2G MAF into a 1G without wiring mods.

Here's a closeup of the 1G MAF plug that was broken out of the 1G MAF.

Here's a closeup of the 2G MAF style plug. This is actually a late 1G transistor plug, so here's the colors I was dealing with:
1 - YB
2 - YR
3 - B
4 - W
5 - YG (moved from pin 8)
6 - BW
7 - Y

Here's another closeup of the 1G MAF plug that was broken out of the 1G MAF. I cut the terminals shorter and bent them away from each other to make sure the wires have no chance of touching. Again, though, I'll be filling that area with WindoWeld sooner or later, to weatherize and protect the solder joints.

This table and pic might be a bit confusing at first, but look at it long enough and it will make sense. The top of the pic has the numbers in pink - these are the numbers of the wires from the late 1G Power Transistor (PT) plug. The bottom of the pic has the numbers in blue - these are the numbers of the 1G plug terminals after translating them from the plug side to the terminal side.

1G PT Wire (# in pink)	1G MAF plug terminal (# in blue)
1- YB	4 on 1G plug
2 - YR	7 on 1G plug
3 - B	2 on 1G plug
4 - W	3 on 1G plug
5 - YG	6 on 1G plug
6 - BW	8 on 1G plug
7 - Y	1 on 1G plug

Here is the plug adapter on the MAF. You can also see the blackpipe coupler I am using to mount the MAF to a 3" mandrel bend to fit to my Frank3 on my red car. My blue car will use a 2G MAF hose with the accordion end cut off and replaced with a 2.5" mandrel bend.

Looking into the back end of the MAF.

The Fernco 1056-33 3" CI/Plastic coupler. I bought it at Orchard Supply Hardware. The internal diameter is a little over 3". It stretches to fit over the MAF, and compresses over a 3" pipe and seals completely. It's a very thick rubber coupler. I used one in a previous 3" MAF hose when I was still running a 1G MAF on my 20G, and it held up over 1.5 years use without a problem.

Here's the modded 1G aircan base (with rotten welds - flux wire MIG). I've elected to use 1G aircans for several of reasons:

1. I can get the bases cheap from boneyards, so I can keep the originals if needed. (FYI, many Hyundais have similar aircans, and they have one less "hump/dome" in the aircan base, so they are simpler to mod).
2. I already have 1G filters for all 3 of my DSMs, so it saves me money over buying a 2G kit.
3. It looks more stock, which matters to the SmogNazis in Kalifornia.

Here's the aircan base set on the 2G MAF.

Here's the 2G MAF from the outlet side, sitting on the 1G modded aircan base.

I'll add more pics later as I finish up the aircan. I'm going to be making mounts that weld to the aircan base rather than the filter side of the aircan, to make switching between a full aircan and a trim ring easier. I'm modding the filter side of the aircan too - I've removed the snorkel and mounts, and will be making a new snorkel that is much larger, and fits directly to the fenderwell, as I have cut out most of the fenderwell where the stock IC outlet comes out (since I have an FMIC). This will make the car look a lot more stealth/stock, and I won't need a ramair dam like I currently have on the car to keep hot engine air away from the intake.