Calling all 1996 5.2L emissions experts

[Dana67Dart]

Well crap.

My daughter bought a new Jeep Renagade.

She gave me her 1996 Jeep Grand Cherokee Limited.

For the past 13 years I have been keeping it up and running, she has done a lot of the wrenching on it.

The jeep is a 2 family jeep.

1. 1996 Jeep Grand Cherokee Limited
2. 2 family car (4 primary drivers)
3. 249,000 miles
4. 5.2L
5. Totally stock
6. Spark plugs, coil, dist cap, rotor and wires have been replaced in the last 5 years.
7. Upstream O2 sensor just replaced, threw a code. Code reset, car driven, computer happy.
8. Threw another code P0107 MAP sensor, but reset itself.
9. Just replaced thermostat, engine was running cold 150. Runs 195 now.
10. I have seen a misfire code but it is not specific to a cyl (that's what prompted the coil replacement)
11. Engine idles fine, drives fine
12. Cat converter has a rattle inside like a loose baffel (not coming from muffler)
13. No smoke from the tail pipe, no soot in the pipe.
14. Only odd exhost issue is the car has had a unpleasant smell from the exhost, none of our other cat cars smells this way, it has smelled this way since my daughter bought it.

Here in CO, they run it on a Dyno. They take the car through a range of speeds (maybe loads????)

The numbers are as follows...

HC 1.3258 (max is 1.000)
CO 15.0507 (max is 15.000)
NOx 3.6253 (max is 2.5)

Thoughts????

 

[royslead]

Couple things: if cat is rattling, it's also allowing untreated exhaust to blow past. That, alone can skew readings. You replaced 02 sensor and cleared code, but did you clear adaptive memory? Disconnect the battery. Intermittent misfire- very possible timing chain, also very possible valve. These, will also cause higher readings. Finally, the bottom of that intake is notorious for gasket failure (not intake to head, though it happens, but rather a pan that literally seals the bottom of the intake). A slight vacuum leak here, will drive the engine rich, as well, because the O2 sees extra air. There are other contributors, but look at these first.My bet is the cat.

 

[Dana67Dart]

I thought about the adaptive memory, but did not clear it. I have 10 days for a retest.

I'll check k to the gasket leak you mentioned.

Thanks

 

[royslead]

I thought about the adaptive memory, but did not clear it. I have 10 days for a retest.

I'll check k to the gasket leak you mentioned.

Thanks

Ok. I have replaced a lot of those cat. converters, for breaking apart as well. When they really break up, they'll cause all sorts of drive ability concerns, especially low power; but I'm guessing you probably knew that.

 

[Dana67Dart]

Have you had any luck with wrecking yard cats?

I was looking at rock auto and a CARB certified cat is 300+ vs 150+ for a non CARB cat

And in CO it is apparent it needs to be a CARB certified cat

 

[niceolddart]

Spend the dough & buy a new cat if you plan on keeping the Jeep. Double check the emission laws in your state. The CARB certified cat seems ridiculous on an older vehicle that probably won't see 5000 miles a year. Some states do have STUPID emission laws though.

 

[Dana67Dart]

CA, CO, MA, NY require CARB cert cats

CO the new CA!

 

[niceolddart]

CA, CO, MA, NY require CARB cert catsView attachment 1715871713

CO the new CA!

I can see the other 3 states, but Colorado too? Yikes!

 

[MOPAROFFICIAL]

I bought a MagnaFlow cat from O'Reilly's and put it on myself I live in California. I would put the 180 or whatever 185 thermostat in it don't put that 195 in it unless you want to lose power. When it runs colder it runs a little richer and you get more out of it. And also use a throttle body spacer from Taylor I use one. And also throw some shorty headers on it carb approved Colorado approved whatever. A lot of why those things start to run from me over the years is the heads totally shot. Probably have stalactites of burnt carbon and oil in the chambers and off the valves guides worn and leaking seals all broken and fall off. The first throw thermostat in it it's cooler and get a catalytic converter if that one rattles cuz yes it's broken up.
The add-ons that I mentioned all picked up the power and never hurt the gas mileage

 

[goldduster318]

First, I can't believe an OBD-II Vehicle gets put on a dyno to begin with!!!

You can look through the throttle body and if you see oil you will really need to do the valley pan. Its best to replace these with a sheet of aluminum, Hughes at least used to sell a kit for it but you could also make one.

If the MAP is dying it won't fuel correctly either. You can read it off of live data, if you do Key-On-Engine-Off, you should be able to compare the value to the value of the barometric pressure in your area. If it's way off it probably needs a new one.

You should also be able to tell us your long term fuel trims.

 

[royslead]

I would not use a salvage yard cat, especially if keeping the vehicle. It sucks you have a C.A.R.B. approved, but that's the way it is. Putting in a colder thermostat will yield a slight amount more power, yes, but also more emissions, which is what you don't want, in this case. The original intake bottom covers were sealed, with a (dumb idea) paper type gasket. The revised version is a metal type one, that I've never had a repeat with. Also, you can compare a MAP sensor's Baro reading with ambient, but it's only one function, at one range - yes , if it's off, it's bad; but you also need to look at the MAP readings at given RPM and loads, as compared to a decent vacuum pump hooked to manifold vacuum, to test that range/function, too.

 

[volaredon]

If it's been 5 years since the last tube up I'd add that to the list. At least cap rotor and plugs. And a PCV.
Those plenum gaskets aren't expensive, usually come with the intake set. Last ones I bought were somewhere around $26-28. And came with the plenum gasket mentioned above.
IDK why people call them "5.2L". They're still 318 CID.
But yeah/ tuneup, intake/ plenum gasket,and a new cat is the least I'd do to something like that.
And id look at the emissions sticker to see if it says anything about CARB or calif emissions.
How many O2 sensors on it? If Cali emissions it will have at least 3 probably 4. If non Cali it will only have 2. I thought most states that follow Cali smog only enacted that well after 1996. If made them as a 49 state version you don't have to retrofit it to Cali emissions. It's what was in effect at the time the jeep was originally built new that it has to satisfy.
If they didn't enact Cali emissions til some year after your model year then they can't expect older vehicles to pass something that wasn't in effect at the time

 

[volaredon]

That intake manifold gasket job is around a 1/2 a day job.
One other thing/ figure on a set of valve cover gaskets added to the intake manifold gasket set. Usually have to take at least 1 VC off, sure makes it easier to get intake manifold back on.

 

[Dana67Dart]

Yikes

I read up on it. Law went into effect 1/1/21 applies to repairs regardless of the OEM origional part.

 

[Dana67Dart]

If the MAP is dying it won't fuel correctly either. You can read it off of live data, if you do Key-On-Engine-Off, you should be able to compare the value to the value of the barometric pressure in your area. If it's way off it probably needs a new one.

You should also be able to tell us your long term fuel trims

Map is cheap enough and easy I'm replacing it regardless. The p0107 cod had been thrown a few times.

I will hook up the PC based code reader and see what images I can get.

 

[Dana67Dart]

And id look at the emissions sticker to see if it says anything about CARB or calif emissions.
How many O2 sensors on it? If Cali emissions it will have at least 3 probably 4. If non Cali it will only have 2. I thought most states that follow Cali smog only enacted that well after 1996. If made them as a 49 state version you don't have to retrofit it to Cali emissions. It's what was in effect at the time the jeep was originally built new that it has to satisfy.
If they didn't enact Cali emissions til some year after your model year then they can't expect older vehicles to pass something that wasn't in effect at the time

The emissions tag says it is a US emissions BUT CO I their emulation if California passed a law that says any replacement cat has to be CARB cert.

The standard is the correct standard for the car. And I looked at all the previous test results and was looking for a trend but the last one which was 8 months ago was significantly lower on NOx and HC and just passed CO.

Turns out the air filter has 10,000 miles on it but doesn't look that dirty but I will replace that too.

And looking at the service manual they all only have 2 - O2 sensors.

The difference between US and CARB seems to be that towards the end of its life the CARB cert cat is better at catalyzing the exhost.

 

[niceolddart]

If you have to have a CARB certified cat, I guess you'll have to pony up the coin. On the intake plenum gasket, which is a common problem with Magnum engines, you could spend the money on a Hughes aluminum piece, (I did on my Dakota & all the gaskets needed come in the kit, except the V.C. gaskets. Awesome piece, but pricy) or you could use the factory one, add lock washers to the bolts or grind the tips of the bolts down a bit, that hold the plenum plate to the manifold, word is that the factory bolts are just a bit too long & don't snug the gasket tight & that's why they develop a leak, & make sure you use a good gasket because it's a lot of work removing the intake. My Dakota wasn't so bad because it was a 95 & pretty easy to get to everything. Hope this helps some.

 

[Dana67Dart]

I read up on it. Law went into effect 1/1/21 applies to repairs regardless of the OEM origional part

Not sure why @volaredon disagreed with me.

Aftermarket catalytic converters | Department of Public Health & Environment

 

[67Dart273]

Seems to me it's time to consider "a different state." The fact that one state decides to live by the n worst emissions laws on top of ridiculous requirements for a vehicle that old is preposterous. The next question is, "just how bad" can the "smog" be there BECAUSE OF VEHICLES THAT OLD?

 

[Dana67Dart]

The next question is, "just how bad" can the "smog" be there BECAUSE OF VEHICLES THAT OLD

(Speaking with a Johnny Carson acent)
It's so bad...

The problem as I see it is like SoCal we have an area where air is brought in from outside the state and it sits here.

When there were fires in Oregon or Idaho ( don't remember which) the sky was orange and it lasted for a few weeks.

Also our state has drank the cool-aid. Wyoming is only an hour away but getting my wife to move there might be too much trouble

 

[Dana67Dart]

Well crap ...

So damn close...

Got the replacement cat Friday.

I was able to break off both u bolts, one was stubborn and I had to cut it, but both came off.

Of course the factory crimped the rear with the u bolt to the point where there was little chance of the cat pipe coming out of the muffler.

So I cut the ends of the old cat off so I could salvage the head pipe and the muffler.

Looking inside the old cat it looked fine

ON THIS END!

Now the other end is a different story

That chunk is not supposed to be loose in there. (Hence the rattle!)


I was able to slit the cat pipe on the head pipe and get it off super easy!
Open pipes on a jeep Grand cherokee

The rear pipe in the muffler got me to the point I give up.

There is another 2.5 inches of pipe inside the muffler, and what looks like a spot weld on the opposite side.

So open pipes to the muffler shop next week it will be.
I don't have access to a tube expander or a welder of any kind, the garage was 20 deg, I tried chiseling the inner pipe along the cut I made with my sawsall, but that only went so far, I thought about slitting both sides of the outer tube (the part that is welded to the muffler) but did not want to make things worse at the muffler shop.

Perhaps if I had a lift I could have gotten the muffler and tail pipe out of the jeep and worked on it more.

Oh well!

At least I did not break anything and only got 1 cut and one hammer to the knuckle of the hand hiding the chissle

 

[volaredon]

I read up on it. Law went into effect 1/1/21 applies to repairs regardless of the OEM origional part.

I'd like to see that. Ive been working on cars and trucks a long time. I've also always read and been told that whatever was in effect at time of manufacture is what a vehicle has to conform to. California or not. And if they only passed that law a year ago, there's no way they can force you to make it pass any standard that came about, later. if it was built as a 1996, 49 state vehicle, there is no freaking way that they can make you retrofit any thing that wasn't there to begin with.

 

[Dana67Dart]

And if they only passed that law a year ago, there's no way they can force you to make it pass any standard that came about, later. if it was built as a 1996, 49 state vehicle, there is no freaking way that they can make you retrofit any thing that wasn't there to begin with

It does not have to pass a tighter limit it just has to be CARB compliant if it is aftermarket, or you can pay the dealer 2x to get an OEM cat.

The People's Republic of Colorado!

 

[MopaR&D]

It does not have to pass a tighter limit it just has to be CARB compliant if it is aftermarket, or you can pay the dealer 2x to get an OEM cat.

The People's Republic of Colorado!

Wish I saw this thread earlier. I live in Fort Collins and have to deal with the Air Care Colorado shenanigans as well. I ended up calling the Denver Air Resources Board to get the real scoop on the cat law because I was hearing a bunch of conflicting crap from my car buddies. In a nutshell, your vehicle does NOT need a CARB-rated cat to pass CO emissions. All they did was outlaw the sale of 49-state cats in the state. The engineer on the phone literally said "You could drive up to Wyoming, buy a 49-state cat from a parts store and install it in your car, take it to the test station and nobody would be able to do anything about it." The reason they put the law into place is because there are so many low-quality aftermarket cats for sale now that go dead after just a few years and CO residents were getting tired of having to replace their cats every 2-4 years; also means a lot of cars driving around with worn-out cats putting out extra emissions.

I also had the "F off Big Brother!" attitude at first but once I learned the details it actually makes a lot of sense. I also learned recently that the Front Range has a really bad ozone problem in the summer time so the emissions laws here exist for at least one legitimate reason. More than one of my car buddies has online-ordered (or drove up to Cheyenne and bought) a "universal" 49-state cat, bolted it in their car and went and passed their emissions test with no issues.

It is wack though they regulate emissions on anything newer than 1975. I hate that so much. When I registered my 1972 D200 they told me I'd need to get collector plates or it would need to be emissions tested!! I just laughed and said yeah, collector plates it is. Extra stupid because emissions regulations didn't even start on pickup trucks until the late 1970s although Kalifornia probably started earlier.

 

[Dana67Dart]

. I hate that so much. When I registered my 1972 D200 they told me I'd need to get collector plates or it would need to be emissions tested!! I just laughed and said yeah, collector plates it is

I'm in FC also.

The year we moved here they turned on the smog check requirement.

My dart had to pass smog to get registered the first time.
2017. I have been told by CO DMV that collector plates still need smog checks but only once every 5 years. And you have to pay 5 years of registration up front.

I read on the state site conflicting info,

I just have it registered as a normal car but due to its age I have to smog EVERY year.

I use the emissions tests as an engine condition meter. This next one will be interesting as I'm burning a bit more oil these days.