OBD1 Distributor wiring loom

[justacruzr2]

Does anyone sell the OBD1 distributor wiring loom? This is the 4 wire 4 pin connector between the ignition module in the distributor that goes thru the base of the distributor and connects to your engine compartment wiring harness. I suspect mine might be bad. A Google search only produced adapter harnesses that convert OBD1 (or 2) to OBD2 (or 1).

 

[69hurstolds]

Can't get it from GM anymore. 3rd party you can, like ebay.

Guessing 307 Olds V8 or Chevy 305?

New is $150.00 + 8.00 shipping, plus any sales taxes.

1985-1989 GM Terminal Block GMC CHEVY TRUCKS BLAZER CK TRUCKS SUBURBAN 1979733 | eBay

1985-1989 Chevrolet Blazer. 1985-1989 Chevrolet Suburban. 1985-1989 GMC Suburban. 1985-1986 GMC C1500. 1985-1986 GMC C2500. 1989 Chevrolet R2500. 1985-1986 GMC C3500. 1985-1988 GMC G1500.

www.ebay.com

You're talking about the Computer connector 4 pin that goes to the passenger side, correct? Olds 307 and Chevy 305 uses GM p/n 1979733.

Do you need one? Ima gonna guess so. It helps to know what engine you have, though. They have different ones depending on your setup. It appears the only difference in the new ones is the color of the retainer block and the wire colors. They still go to the same places.

It JUST SO HAPPENS I have a good, but used 1979733. Today I was putting together a Delco distributor with all new Delco parts (except for shaft and gear). The distributor I took the shaft from still had its electronics.

The end of the security clip which holds it to the module broke, but the darn thing is so tough to put on and pull off, you wouldn't need it anyway.

It actually mounts inside the distributor with a little screw and the wiring is hanging out the side of the distributor.

Part is delineated with the red arrow below. The yellow arrow is pointing to the little piece of security clip that is broken off the used part. It won't affect the operation at all.

If you think you can use it, I'll send it to you for the cost of shipping.

Make sure it's the part you need, though. If it's a 6 cylinder, it could be different, I don't know.

 

[justacruzr2]

It's the SBC 305. I only suspect that because when installing the engine, the distributor bumped the firewall and that's exactly where that wiring comes out at...the back of the distributor. The past couple months occasionally the engine will just stall without any warning. I have to pop open the hood and wiggle the main wiring loom that the distributor wiring connects to and then it starts again. That's pretty annoying. And I do realize it could also be something in the main wiring loom that the distributor connects to. But it never did that in the car that it came from. Electrical issues are so much fun! Anyway, I'm going to try and get a new one from the maker of the distributor first...if it's available that way from them.. It's a new distributor.

 

[69hurstolds]

Oh. Not a Delco. I see your dilemma.

 

[justacruzr2]

Oh. Not a Delco. I see your dilemma.

It's a Cardone but when connecting that loom to the engine compartment loom one pin got smooshed. We straightened it out but I think this might be the cause of why the engine will just stall occassionaly. When I get out of the car and wiggle that wire it starts back up. Cardone doesn't sell that loom separately. It is the same as the GM loom though. If you still have that loom let me know how much to ship it to me. Gratefully thanks.

 

[69hurstolds]

SOME 305s use a different p/n. Please verify that this is the correct one you need. The one I have fits the 7 pin module. Check to make sure you have the right module. It won't fit the 4-pin.

The 4 pin module jobbies use p/n 1892261. Which is still expensive to find new.

Corvetteparts.com sells a reproduction for like $30.95 if that's the one you need.

1981 - 1991 Corvette Terminal Block, distributor ignition with capacitor & harness: CorvetteParts.com

1981 - 1991 Corvette Terminal Block, distributor ignition with capacitor & harness 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991

corvetteparts.com

Lemme know.

 

[justacruzr2]

SOME 305s use a different p/n. Please verify that this is the correct one you need. The one I have fits the 7 pin module. Check to make sure you have the right module. It won't fit the 4-pin.

The 4 pin module jobbies use p/n 1892261. Which is still expensive to find new.

Corvetteparts.com sells a reproduction for like $30.95 if that's the one you need.

1981 - 1991 Corvette Terminal Block, distributor ignition with capacitor & harness: CorvetteParts.com

1981 - 1991 Corvette Terminal Block, distributor ignition with capacitor & harness 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991

corvetteparts.com

Lemme know.

Mine is the same as the one in your picture. On the side that the 3 pin connector connects to is, of course, that 3 pin connector and then a 2 pin connector right next to it. Mine is the 7 pin ignition module. So I think yours is OK. Funny thing though....That loom on eBay that was being sold for $150. You can get a brand new distributor on Rock Auto for $99 that includes that loom. Why pay $50 more?

 

[69hurstolds]

Mine is the same as the one in your picture. On the side that the 3 pin connector connects to is, of course, that 3 pin connector and then a 2 pin connector right next to it. Mine is the 7 pin ignition module. So I think yours is OK. Funny thing though....That loom on eBay that was being sold for $150. You can get a brand new distributor on Rock Auto for $99 that includes that loom. Why pay $50 more?

Reason? Delco and GM.

Cool about the 7 pin. I'll box it up and let you know.

PM me your snail mail addy.

 

[69hurstolds]

Man, am I stupid. I'm not thinking right for some reason. It just hit me, the 1892261 is the harness for ignition coil pulse along with the radio noise suppression condenser.

They call BOTH "terminal blocks" in the parts catalog and both show "Harness Assembly" on the parts baggies. But the older Delco boxes they used to come in both say "Connector". It's easy, at least for me, to get stuff mixed up.

ANYWAY.......

The 1979733 is the CCC harness and has the 4-pin plug to go to the ECM wiring plug. Three wires. The two that are left on that side of the module are for the pickup coil., and the other side has the two prongs for the 1892261 harness. Yi yi yi, I don't know where my mind's been lately. Old age. Yeah, that's it.

So you're needing the 733 harness. It plugs into the 5 pin side of the module. But only uses 3 of the pins. But has 4 pins for the ECM plug. One small caveat, though. I broked the retainer clip off when I removed it (nearly 40 years old plastic) but where its at, that sucker isn't going anywhere anyway once installed.

 

[justacruzr2]

Man, am I stupid. I'm not thinking right for some reason. It just hit me, the 1892261 is the harness for ignition coil pulse along with the radio noise suppression condenser.

They call BOTH "terminal blocks" in the parts catalog and both show "Harness Assembly" on the parts baggies. But the older Delco boxes they used to come in both say "Connector". It's easy, at least for me, to get stuff mixed up.

ANYWAY.......

The 1979733 is the CCC harness and has the 4-pin plug to go to the ECM wiring plug. Three wires. The two that are left on that side of the module are for the pickup coil., and the other side has the two prongs for the 1892261 harness. Yi yi yi, I don't know where my mind's been lately. Old age. Yeah, that's it.

So you're needing the 733 harness. It plugs into the 5 pin side of the module. But only uses 3 of the pins. But has 4 pins for the ECM plug. One small caveat, though. I broked the retainer clip off when I removed it (nearly 40 years old plastic) but where its at, that sucker isn't going anywhere anyway once installed.

View attachment 245652

Yep. Of the 4 wires that plug into the engine compartment wiring harness, one is for ground. You might notice that if you wiggle the black wire, the flat silver blade with the hole in in that screws to the base of the distributor will wiggle a little too. Thanks again for your PM.