Well, I promised a week or so ago that I'd post the procedure with pics of what's involved for the pcmforless.com ECM chip upgrade. So here it is.

It really is a stupidly easy upgrade. Probably easier than changing your wiper blades. I post this only to quench the fears of those who are afraid of trying it. Honest: if you can put air in your tires without hurting yourself, you can do this upgrade in about 15 minutes.

Note: this procedure and related pics are for 1990-1993 Corvettes. Earlier models had the ECM stashed up under the passenger-side Breadbox. Later models, you need to 'flash' the ECM (or send it to pcmforless.com for an exchange programmed unit).

Another Note: GIJoe: please put this in your wonderful VATS-disable website.

1) Pop the hood, and locate the ECM. You can't miss it: the ECM is on the driver's side, above the battery, as shown in the following pic:



2) Pry off the plastic cover that protects the wiring harness connectors. It kinda has a velcro-like stuff that sticks it to the top of the ECM. When removed, the ECM will look like this:



3) Remove the three nuts that secure the ECM. These are 10mm nuts. For the one near the cruise-control gadget (farthest toward the driver's side of the car) you need a socket extension.

When the three nuts are removed, carefully turn the ECM upside-down. You do not have to unplug any of the wires on the ECM. This will reveal the cover plate on the ECM, as shown in the following pic:



4) Remove the four hex-head screws that secure the cover plate. These are small SAE-size screws (not metric). With the cover removed, you can access the stock programming chip. It's right under the cover. My chip was blue plastic. Note that there are plastic retaining clips on each end of the chip, as shown in the following pic:



5) Fold down the plastic tabs that retain the stock chip. They fold down, out away from the ends of the chip. This will pry the chip up slightly so it's easy to remove. Then, just pull the stock chip straight up and out of the ECM.

6) When dealing with any computer chips, static electricity is an issue. Before you continue, discharge any static electricity you may have on your hands (like... by pulling on a big wool coat). To do this, just pat the plenum on the top of the engine. Say something soothing to your car like: "Good girl... this will all be over in a minute..."

7) Connect one side of the old stock chip onto the connectors of the chip-adapter provided by pcmforless.com. Pay attention to the orientation of the stock chip, and where it plugs into the adapter. Complete instructions are provided by pcmforless.com when you buy the chip-upgrade.

8) Plug the new pcmforless.com upgrade adapter into the ECM. Push it straight down onto the connector. Fold the two plastic retaining clips back up over the ends of the adapter, so it looks like this:



9) Put the cover back on the ECM (4 screws). Flip the ECM over, and put it back into its bracket. Secure the 3 10mm nuts. Replace the plastic cover over the wiring harness.

Done.

 

I'm sure everyone knows this, but always disconnect the negative (-) battery cable before working on electrical items and reconnect it when done.
Some do it without, but I don't recommend it.

Tom Piper

 

Nice write up and pics.

 

NOW, I'm not afraid to do this any longer!
Bernie

 

woo hoo! Thanks! I will get this on the site as soon as possible! That is WAY different than us 89 and older owners Thanks for all the pics, that is really going to be a big help to those in the future. I will try and get this stuff up tomorrow

\



***Edit - Info has been added to the site.

 

Boy! I wish mine were that easy to get to...

 

 

Text and pics saved to my computer with thanks. Question: do the chips all give a VATS delete or do you have to ask for it?

 

You ask for it. Check out their website and order form and you'll get a good understanding of it all

 

its all optional.
the order sheet has stuff like

X - Go Faster
X - Remove stupid VATS
X - Remove useless exhaust codes since I gutted most of it
X - Remove LTPWS error codes since I removed that too