93' Grand Cherokee Runs Rich?

Hi Bill, Oh man,,,, noooooo... I replaced this thing one other time I was having a problem. 2 hours on my head and three skinned knuckles. Plus two cop calls for shouted public obscenities. This was not fun. And, it didn't solve the problem at the time. Well, at least I'm on vacation and I do have one on hand. I seem to remember getting the wrong part from the dealer the first time. Thanks Bill. And I concur: God Bless America.

D did pass the time by typing:

Before going any further, pull the engine codes.

How old is your catalytic converter? A plugged cat can cause the symtoms you describe. As can a few other things.

Great suggestions all. The converter is 258,000 miles old. (Authenic original equipment) Heh Denny

Thanks Will. These are great suggestions too. Denny

I pulled the codes. They were 1,2,5,5 So, is that a 25 code? 12 code? I get confused. Thanks. Denny

Now I see. It's a 12 code. Of course, the battery was disconnected Monday on the alternator replacement. And 55 to indicate the end of the codes. Denny

D did pass the time by typing:

Yep.

That means the engine isn't picking up faults so your problem is either in the intake, ignition, or exhaust.

Given the milage you claim on the cat, dollars-to-donuts it is plugged. A new one should cost about 100$ from any local muffler shop. Aftermarket cats are good for about 80k-100k miles

Thanks Doug. That makes sense. I'll have the cat checked out today. I also just remembered, I put a can of STP gas additive in the tank of gas currently running through. I wonder if it may have stirred some gunk up. The old girl seems to be running better as it works through. I normally don't like to use that stuff, but it was free with 5 qts. of Castrol. Been rolling around in the rear footwell for a few weeks and I just happened to see it and use it the last fillup. Denny

D did pass the time by typing:

STP is good. The best (my opinion) out there is the Chevron Techron fuel system cleaner. Make sure the bottle says to use only every 3000 miles. The daily tank ones are too weak. Although I do use one from NOS that contains a fuel drier for those times I pick up a tank of slurry.

The other thing (I forget, too many messages, too small a brain) have you replaced the fuel filter?

Hi Doug, It did cross my mind to change the fuel filter. Going to do that tomorrow. After all these miles (258K) I'm only on the second filter. Thanks for all the help. BTW, the old girl's been working pretty good the past two days. Denny

D did pass the time by typing:

The fuel filter is a 10,000-30,000 mile item on the 93 depending on how clean the local gas pumps are.

Real easy to get at, just remember to bleed off the pressure at the fuel rail test port (looks like a tire valve) Put a big wad of paper towel under the valve before you press it cause gas is going to come out. If you don't relieve the pressure you will get showered soon as the fuel filter is disconnected.

Be careful with the quick connects, they are expensive to replace, use a fingernail or thin jewelers screwdriver/mashed paperclip to free the clips. You basically pry back the tabs so they slip over the bump on the filter tubes.. Don't have a pic but you will see it when you look at the new filter.

Before you put the new filter in, smear some oil on the ends, that makes it easier on the old o-rings.

Use the rubber caps that come with the new filter to block off the old filter ends

And finally, wear protective splash goggles and old cloths because you will get gas running down your arm.

L.W. ("ßill") Hughes III did pass the time by typing:

Drivers side, just in front of the fuel tank.

No shield, just a clamp type holddown.

L.W. ("ßill") Hughes III did pass the time by typing:

I'll do that. Probably just heap it in on the sensor page by the fuel rail info. Too dark to get a better photo now tomorow mebby.

DougW did pass the time by typing:

Done.

Not good, but the pics are there now.

Either or. Eventually the cox.net is going to be turned off, but for now I'll put it both places.