Just wondering the best way to check an emission harness before I install it? It is a replacement harness. Is checking wire resistance the way to go? All clips are intact except 2 which I can crimp back on.

 

That's a good way.

 

resistance check is about all you can do. unfortunately it won't always point out an issue such as frayed insulation where 2 wires are rubbing together causing cross continuity, that can be time consuming to check for. well maybe not too bad but it is a good idea to check as well, just doubles the check out time.

 

Thanks for the inputs. I may unravel some as far as practical to take a peak on wire condition. I noticed my 90 emission harness has the blue/orange air bag wires. The replacement is supposedly from an 88' w/no airbag. I reckon I can swap the airbag harness portion over?

 

Have fun with changing harnesses that are NOT the same series!
(you should know that by now!)

 

Its the emission harness and all connectors are the same. I did ask the forum if they were interchangeable before I bought it. Looks good.

 

Checking continuity of an emission harness I find this wire which I think is for the 02 sensor, but I cut the protective sleeve and see the wire is much thicker gauge than my previous harness 02. And I don't see the wire come out the other end (ECU end) that is the same size. Anyone recognize what this is?

 

S4 and S5 EM harnesses are not the same and not even close to being the same.

An 88 EM harness will not plug into a series five ECU nor mate with the Front harness.

If your new harness does connect to the series five front harness and ECU..........then it ain't a series four 1988 EM harness but a series five EM harness.

 

Must be a S5 harness then. Injector clips fit and everything 99% looks the same. ECU plugs in as well.

I went back and checked and its from a 89' with no air bag. Oops, sorry I had my info wrong.

 

it looks like o2. check resistance between that wire and pin 2c on the harness

 

Thanks! Saved me time alot of time. 02 it was.

 

Should I be getting any continuity between these 3 grounds? Thanks.

1) Vacuum bracket ground
2) Fuel injector ground
3) Ground at ECU plug