Pics of factory exhaust? Emissions failed...

[mkbruin]

So, the '88 failed the E-test today. Just over on HC (3.1 @ 3.0 allowed) and failed visual for catalytic converter.

 

Sure enough, took a look, and there isn't one on there. Strange that its passed the last three times, since we have never made any exhaust mods in the last four years that we've owned it.

 

Anyways, my old '89 had a different system than this '88, both 4.0 and manual trans. Can anyone post up pics of the factory exhaust system? Routing, cat location, etc?

 

We are probably going to pick up an exhaust with a cat from an individual parting out their car and just burn it in at some point before the muffler, but if we can find a full system from a MJ or a partial (front half?) from a XJ we may jsut bolt/burn it in.

[jimoshel]

I do not have a '88 MJ with the 4.0. I do have a '87 and a '89. They are identical. Just gotta assume (*) that the '88 would be the same also. I have a '87, '88, and a '89 XJ with the 4.0. The exhaust is identical on all 5 vehicles. That's from the engine to the rear of the muffler. The difference in length is in the tail pipe. Did not check for sensors on the cat. Just checked the physical layout for swap fit. Jim

[mkbruin]

That's good to know. At least it *should* be the same on any renix era engine.

 

On mine, its header, into a small section of tube with several sensors flanged at the bottom, then straight pipe down, bending around, and heading backwards along the passenger side to the exhaust.

 

I can't believe there isn't a cat on this, and that it never was found with inspections before now.

 

 

anyone know the the system on a 4 cyl was the same as the 6? Or, at least reasonably close?

[dasbulliwagen]

Recently gutted the cat on mine, but I'm 99% sure its the same on the 4 cyl, it is 2 1/4" inside diam for bot the 6 and the 4, so a 4cyl one should work too. Mine has a 4 bolt flange at the trans crossmember where the cat bolts up to the exhaust downpipe from the motor, then after the cat is a section of pipe that heads into the muffler... no sensors as the cat is not monitored after the fact by the renix system. I think with as close as you are to passing, anything you put in there should work... just don't put one in from a 2.8 V6 as it is GM style and requires an air pump. Good luck.

[mkbruin]

Thanks. We are scanning the craigslist 'parting out' ads looking for something to bolt on, but have access to a welder if we absolutely need to cut and burn one in.

 

We are going to be selling this one once we pass emmissions, so we don't want to throw hundereds of dollars into it if its not absolutely necessary.