swapping parts from 1991 to 2001

Well, looks like my 1991 XJ engine is too old to pass emissions testing in NJ. I'm thinking of buying a 2001 and moving my axles, lift kit, bumpers to a newer un-rusted model.

Anyone see any big problem with this?

My lift has drop down brackets for the front links.
I also have a VERY fat track bar. Have the stock dana rears, 30 HP front straight axle, not disconnect; 35 rear. 355:1

Most lift kits I see advertise 1984-2001.

Everything will bolt up, but why? I'm sure you can make the 91 pass easier and cheaper than going to a 2001. What's failing emissions? CO? HC? NOx?

fails CO.
replaced the old catalytic converter due to a rusted away connector
Maybe the new one is too small
oil pressures real low when warm, lots of oil in air box, most likely need an engine rebuild to pass.

I am going to try some things to pass but it's not likely to make it this year.

hmmm... got some vacation time or weekends off? Engines are under $200 at the you-pull up here in central mass. Let me know, my new job doesn't start till beginning of August and I'm sitting around with my thumb up my ass, you could reasonably expect to drive up Friday night or Saturday morning, hit the junkyard, get an engine, install it in my yard, then drive the damn thing home Sunday and pass Monday.

Try replacing the o2 sensor if you haven't already, it sounds like it is running lean. I've never had a too small cat cause high CO readings, but the engine running lean because the o2 sensor is gunked up or one of the other sensors is bad will definitely cause it.

I'm with Kastein.

Oil in the airbox is USUALLY a sign that the CCV system is plugged--when was it serviced last?

At least run a compression test first, maybe followed up by a leakdown test.

joe_peters said:

...--when was it serviced last?

Click to expand...

:roflmao::roflmao:

He's got a good point.

Mine was horrifically plugged when I swapped the old engine out of my 91 MJ. So badly plugged that I couldn't push a drill bit through it by hand, I had to soak it in acetone and twist the drill as I pushed to scrape the gunk out. It was all plugged up in the metal fittings screwed into the manifold that the CCV system hoses attach to.

I never figured that would happen, was swapping the engine for another reason (deathwobble broke the passenger engine mount right off the block) and discovered that while swapping the fittings from the 91 manifold to a 96-98 manifold so I could change to the later serp belt tensioner setup.