1991 4.0 5spd ECM

So I fried my ecm. Looking up the numbers for a replacement as this is where I get confused. The number on the ecm is 56005717. From what I can find, this ecm is for a federal emissions automatic. Should I realistically have another ecm, or just replace in kind? Also, if looking at salvage yards, are there other compatible years, or does the ecm have to be 1991 specific?

I believe any 1991-1995 from a non-california manual will interchange.

That's what I thought, but wasn't the sure. But why would my California emissions xj with a 5spd have an ecm that is federal emissions automatic transmission? Also, never had any drivability issues as it was set up.

jeddi03 said:

That's what I thought, but wasn't the sure. But why would my California emissions xj with a 5spd have an ecm that is federal emissions automatic transmission? Also, never had any drivability issues as it was set up.

Click to expand...

Looking up 56005717, https://www.autoecmstore.com/products/56005717 says manual, california model.



Most of the places like RockAuto list 56005717 as compatible 56027528, which the autoecmstore says is auto/federal. Could be they really are interchangeable. I don't recall whether the OBDI ECMs would throw codes if the tcm wasn't detected, and whether they all had the same number of O2 sensors.

Thanks. Didn't have any luck at the local salvage yards yesterday. All the xjs that they actually had (very few any more at the yards) were already picked over and the ecms...gone.