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New Jeep...new problems!

Okay, so I am overdue for an update. Here you go with some pictures.

Here are some pics of the plugs I took out.


A close up


I also replaced both 02 sensors...They both were looking good:eyes:

Below is upstream


Below is downstream


I apologize about the pictures. I forgot which was the correct way and I can't edit the post.

So far, I have replaced the 02 sensors, the plugs, the blower motor resistor, and plug wires. The Jeep is running exceptionally better but still being a gasoholic. Still running rich but throttle response is back. I don't have hard starts or anything like that but I'm thinking the Jeep is running rich at idle and lean through the rpm band. It's just a hunch. I'm thinking my fuel pressure regulator, fuel pump or fuel filter is bad (or a combination).

What do you think? So far, I've rid lowered total DTC's from 7 to 1.

current DTC: p0171
The main thing is to get the correct plugs - Champions!
I appreciate all of the help so far. The Cherokee is running better. I have throttle response but gas mileage is still horrid. I'm estimating around 8 to 9 mpg. I replaced the o2 sensors and the plugs and the wires.

I also hooked up a fuel pressure guage to the rail. I checked the pressure with the Jeep off. It was approximately 42psi. With the motor running it jumped up to about 46psi. I hit the throttle while watching the gauge and the needle didn't move. It sounds like the problem is not a fuel pressure or flow problem. I guess it could be leaking injectors. But, all of them are bad/leaking?

The diagnostic code that usually keeps reappearing is po171. I checked the fsm and it says that the computer detects a lean condition but the Jeep has overcompensated for this causing a rich condition. I unplugged the air intake temperature sensor and that triggered a code but didn't immediately change how the Jeep ran. I unplugged the map sensor and it nearly died immediately. For sure, the map sensor is working. The air intake temperature sensor, not so sure. Both sensors, individually, did produce codes when disconnected. However, only the map sensor immediately affected the running of the Jeep.

I didn't touch the TPS.

Any ideas? I need to smog this thing at a bleeping Star Station. I just bought it but it's giving me headaches. Any help is appreciated.
You need to check for vacumm leaks around the intake and throttle body. Make sure your PCV is properly functioning, and also check for exhaust leaks.
In checking for exhaust leaks get a mirror and a flashlight and carefully examine the header collector. There is a good chance you have one or more cracks in that area. Also check all the ports up at the head.

And while you are worrying about exhaust leaks you should probably also worry about the condition of your motor and trans mounts. The two tend to be related. If you find that you need to fix your exhaust you probably need to also fix your motor and trans mounts.
You haven't said what brand parts your using? Jeeps are really sensitive about using Mopar parts(and you can still get them for your year). They also care about O2 sensors? Do you have access to a scanner preferably with data-logging?
I used Denso o2 sensors. The exhaust probably needs work. I seafoamed the Jeep and had smoke coming out of the engine bay. Initially, when I restarted the Jeep after initial soak, there might have been more smoke coming from the engine bay as opposed to the tail pipe.
I don't have access to a scanner at the moment with data logging. I could get one though. Are you looking for long term and short term fuel trims?
I don't have access to a scanner at the moment with data logging. I could get one though. Are you looking for long term and short term fuel trims?

You would be looking at "all" the sensor inputs.
Ok, so over the last four or five days I have been getting around in the Jeep. I have put some miles on her. I dumped a bottle of Berryman's fuel injection. cleaner into the tank and filled it up. The CEL went away almost immediately after this. I have yet to get the CEL to come back. The CEL code was for po171. According to the factory service manual, that code means that there is a lean condition that causes the computer to overcompensate which results in a rich condition.

I'm not sure exactly what the Berryman's did; however, I did notice when I first bought the Jeep that the fuel gauge would wander back and forth a lot. Imagine the needle slowly moving from empty to three-fourths of a tank or more. That wandering did minimize but it's still there. I checked fuel mileage using the odometer reading and amount of gas needed to fill up. After the Berryman's, which I've used a little over a half tank of fuel, has increased my mileage from around 8 to 10mpg.

My thoughts are that the fuel float is messed up and possibly debris in the tank??? i don't know. That was just a thought and a question to you more experienced Jeep enthusiasts. However, on the last fill up yesterday, as soon as I pulled into the station, white smoke started coming from the engine bay. I pulled up to a pump quickly and shut it off. I went to open the hood and look inside. There wasn't anything I could see wrong. NO more smoke or anything. I fueled up and looked again inside the engine bay and didn't see anything.

After this, I drove away but noticed that the engine coolant temps rise more quickly. Yesterday, I wanted to inspect and replace the the differential fluid. I took off the cover, which was not easy, and inspected the ring gear and the spider gears. It looked okay to me. I was looking for heavy scarring or chunks I missing. I didn't see any. The fluid was only slightly dark but not too bad. What worried me is the pan was littered with glitter. Little tiny specks or flakes of metal shavings. I have a few pics I'll post later.

I read up about which fluid to put into the diff. However, it was hard finding something. One of the oils I looked up was the Lucas oil 75w-90 synthetic. It says Gl-4 and Gl5 rated. However, I saw multiple people review the oil on Amazon that it put the oil into their WJ's and XJ's and everything was fine. One person even edited their review and said after 50 or 100k miles that the rear end hadn't exploded or anything. I hope this oil is ok. I have a RWD model and I am pretty confident that there is no locker so I probably don't need the 4 oz. friction modifier but I added one anyway from LubeGuard. I love their stuff. Do you guys have any experience with them? What about Lucas or Amsoil Synthetic in the diff? Yay or nay? Which friction modifier do you guys use? Does it matter?
Also, to finish up my last post, I noticed yesterday that the overflow tank was empty. It took a half gallon of distilled water to fill it up. I thought maybe there was air in the cooling system somewhere so I started it up with the cap off of the radiator and it was full. However, the water was a murky brown. Then after some time, it slowly was spilling out and the fluid became green. I was waiting forever, around 20 minutes, but the thermostat didn't open? I finally started revving the motor and watched the coolant disappear momentarily as I warmed it up. This further mixed the fluid and turned it more green but there was a lot of tiny bubbles. Is this worrysome? I also have a power steering leak. Haven't yet located the source. What kind of fluid do you guys recommend? I was thinking either LubeGuard, Lucas, or Triax but I am open to suggestions. Right now, when I make left-hand turns, there is some intermittent whining. I wasn't sure if it was from the rear diff or from the power steering pump up front. Any advice is appreciated.
I would be inclined to connect your smoke from under the hood and you empty overflow bottle with a probable coolant leak somewhere.

I would plan to flush and replace the coolant as well as replace the radiator and heater hoses. Thermostat and radiator cap would also be worth replacing. Then see if you continue to lose coolant or not. Try to get a look at your freeze plugs. Those are another potential leak site.

I would not worry about a friction modifier. I doubt it matters which one you use, and you probably don't need one anyway. What I would be inclined to do is go into a Jeep dealership with your VIN and ask them to print out your Jeep's build options. It will be several pages listing everything from interior and exterior colors to axle ratio and tire size. It will tell you if your Jeep came with a towing package or any other "heavy duty" options. Having this information makes it much easier to decide when faced with options for parts.

Regarding your power steering leak, know that there is an O-ring between the plastic tank and the metal body of the pump. A replacement O-ring may be all you need. Somewhere around here the part number for this O-ring and its dimensional specs are available (the toy computer I am using right now is no good for searching or I would post a link). Hunt around and you should be able to find the information. If not, inquire and I will find it for you. The job of replacing it is a minor PITA on account of the clips that hold the tank and pump together, but it is a do-able job nonetheless.
Okay, so yesterday I was able to get the computer to throw another CEL...after nearly a 100 miles without throwing one. This one was po441. And, I have a coolant leak somewhere.

I did a drain and fill on the tranny and the transfer case. My Jeep was originally a RWD only but the previous owner installed a transfer case when the old tranny went out. This Tranny only takes approximately 2 1/2 quarts of fluid.

I was able to get this number off of the tranny if it helps anyone help me identify the transmission.

Aisin 898012

I wasn't sure and I kept trying to identify it but finally said screw it and threw in Valvoline MaxLife ATF fluid in there.

The transfer case is a 231 J. It had less than half a quart of gear oil in there. I replaced it with the Valvoline Maxlife ATF until it was full.

The Jeep drives smoother and doesn't lurch forward after letting go of the brake from a stop. Shifts are a lot smoother. It did have fluid in it...but it was dark chocolate.

Any help on transmission identification would help.

In regards to the coolant leak. I have noticed for the last week or so that as soon as I shut off the engine I can hear a dripping sound but it sounds like the dripping is coming either from the engine or radiator. Maybe that is affecting the coolant temperature sensor and thus my extremely rich running condition and gas in the oil???

What's the procedure for flushing the radiator out? Special radiator fluid recommendations? Should I change the thermostat as well?
Any reason in particular you are partial to that Autel? It looks like it is around $60 or so.

It reads my abs sensors. The abs light turned on now and then.
So I was able to find out that my front passenger sensor readed the speed slower when accelarating. Replaced the sensor myself and de abs light never went on.
Any help on the transmission identification would be appreciated.

aisin 898012

That's the information I could see on the tranny.

I put Valvoline Max Life ATF in there. It only took 2 1/2 quarts for a drain and fill. That seems a little low to me. I put more fluid in my Camry when I do a drain and fill.