ECM Wire Harness Removal

[dougfather]

I am swapping a 231 V6 to a SBC 350 in an 84 GP. I plan to use the EGR and Cat for the emissions (classic plates in PA may not require them, but I'll keep them there just in case). I won't use the ECM though.

Anyway, I was wondering on how to remove the ECM wire harness? I noticed this is integrated with the AC/Heat wiring as well. Any tricks here? Anything I need to watch out for?

 

[ryanwitski]

I'll tell you what I did but it may not all apply to you. I unplugged the ECM first. Next I unplugged The O2 sensor, carb emmissiond wires, and so forth. I just followed All the wires and snipped The ECM connectors off and just stripped in down as much as possible. I got rid of my AC eventually but You could put in a switch somewhere nice. I also eventually got a block off plate for the EGR. I also got rid of the coal canister and got a used carb and vac. adv. distributor. I'm in ohio and have no problems. (I also put true duals with no converters... also for some reason the pollution pump "fell off" and I didn't put iot back on. lol.

 

[Chevyman85]

Taking out the ECM module will make all of your emissions brain dead. Your Check Engine like will be on constantly. I'd recommend taking out all of the emissions if your taking out the module. Your AC and blend door are vacume controlled, so if you remove the stock canisters you'll have to create an aftermarket setup. Other than that you should be fine.

 

[ryanwitski]

brain dead emissions control. Isn't that the point! lol. Glad i don't live in the states ran by demacrates and green parties!

 

[Chevyman85]

brain dead emissions control. Isn't that the point! lol. Glad i don't live in the states ran by demacrates and green parties!

I hear you there! What are the emission standards like in Ohio? I have to deal with all kinds of smog bullshit here in Washington

 

[ryanwitski]

get this... NONE! no inspections except in columbus, cleveland, cin, and akron. and they are not bad with old cars the standard is low. I removed every piece of emissions control so my car does not look like it's on life support. The cops are too dumb to know my car came with that stuff and at over 20 yrs. old I have no more restrictions! I feel bad for you guys, I know people in CA always worry about the emissions.

 

[bill]

Re:

get this... NONE! no inspections except in columbus, cleveland, cin, and akron. and they are not bad with old cars the standard is low. I removed every piece of emissions control so my car does not look like it's on life support. The cops are too dumb to know my car came with that stuff and at over 20 yrs. old I have no more restrictions! I feel bad for you guys, I know people in CA always worry about the emissions.

Well...the fact that a major RIVER once caught on fire in OHIO may be a sign of total lack of concern for the enviroment....just saying.

 

[pontiacgp]

Anyway, I was wondering on how to remove the ECM wire harness? I noticed this is integrated with the AC/Heat wiring as well. Any tricks here? Anything I need to watch out for?

Easiest way is to get a wiring harness from a non computer car for the engine compartment. I did that for mine when I had the engine out and it cleaned up the wiring real nice...and don't forget to plug the firewall where the wiring from the ECM came thru

 

[Blake442]

...I noticed this is integrated with the AC/Heat wiring as well. Any tricks here? Anything I need to watch out for?

It's actually separate.
The HVAC wiring is contained in it's own rubber grommet that goes thru the A/C box itself.
Then just below it is the grommet for the computer. You'll have to remove, or at least loosen the back side of the fender well to get at it.
There is a metal bracket that's held in with two 7mm bolts I believe. Just unhook the computer and pull the whole thing out thru the the firewall.

On both my 442 and cutlass wagon, I sliced the grommet open to get the wires out, filled it with sealant and reinstalled the grommet and bracket so I didn't have an open hole and then I can run other wires thru it in the future if I ever need to.

 

[bill]

...I noticed this is integrated with the AC/Heat wiring as well. Any tricks here? Anything I need to watch out for?

It's actually separate.
The HVAC wiring is contained in it's own rubber grommet that goes thru the A/C box itself.
Then just below it is the grommet for the computer. You'll have to remove, or at least loosen the back side of the fender well to get at it.
There is a metal bracket that's held in with two 7mm bolts I believe. Just unhook the computer and pull the whole thing out thru the the firewall.

On both my 442 and cutlass wagon, I sliced the grommet open to get the wires out, filled it with sealant and reinstalled the grommet and bracket so I didn't have an open hole and then I can run other wires thru it in the future if I ever need to.

The power for the HVAC comes from this harness, correct? I noticed 2-3 wires that look like they were mounted to either a ground on the engine or the battery cable post on the starter of the 3.8L v6. Right now they are not hooked up. Would this be why my blower motor has no power? Do I have to connect it to the starter or can it be rerouted elsewhere?
thanks!