Possible new engine? If so... (code P0120)

[Signaleer]

Hey crew,

So, the 2002 Liberty (which I just put some money into) may have finally given up the ghost. I will take it to a mechanic Monday to see if I can learn more.... but this forum may know more than everyone.

Here's the story. :favorites68::favorites68::favorites68:

The 02 Liberty Limited (3.7 V6 Gas) has 185K miles on it. It has been running great. There have been a few times in the past when it started and the idle seemed off, really rough at start. I'd goose it and it would find its grove. It seemed like it did this when I started it fast and was shifting while starting it (I'm exaggerating, but stating I was in a hurry). It has never been a problem.

Today, I drove to mom's... parked it. When leaving, started it and it was bad. I heard distinct ticking, and it seemed like it was running on 4 or 5 of the 6 cylinders. I was also low on fuel. I got it started by presing the gas pedal, eventually.

I made it to the auto-parts store and bought some oil (it was very low), and some Lucas fuel cleaner and lucas oil treatment (hoping). Oh, and I also got a tank of gas prior to adding the fuel cleaner. (Well, I added just a bit before I got my gas and then added the rest after 15.5 gallons). I also had them pull codes. The codes came back P0120 and 13 (according to the guy who I think had a high school education...)

Now, it is running, but will no idle and there is some smoke coming from the exhaust. (I honestly can't tell if it is smoke or un-burnt fuel?)

If I am coming to the stop light I have to put it into neutral and keep a little gas on to keep it somewhat idling. I do think its probably oil... (the ticking when I first started it at Mom's... sounded 'valvy' to me.)

Although there is no ticking now that I can hear. It is running rough and doesn't really idle when coming down from normal rpms.

When I gun it (my dad's theory to break free stuck parts) it seems to do ok. I can't really tell if all cylinders are firing but it does get up to full RPM.

So, I either broke a piston, valve, or something else right? If the smoke I am seeing is blue/white - that's oil in the combustion chamber right? Nothing good there. Regardless of other issues that may be present, that means show's over right?

Or should I replace the Throttle Position Sensor (which I think is the code P0120) and that could that solve all this?

I am not thinking so...

So, if I have to replace an engine on a 2002 KJ - who, where, how much? Has anyone done this and have recommendations?

Thanks,

Ed.

 

[M38 Bob]

" (according to the guy who I think had a high school education...) "

Never got a high school diploma, much less a GED myself. Guess I should be happy that I don't sit around drooling on myself, huh? I've run across a lot of folks with alphabet soup behind their names that don't have enough sense to pound sand in a rat hole.

Bob

 

[Signaleer]

Your right, that was misplaced. Neither did my mom. I was trying to make light of the situation (aka the guy said to me "I'm the parts runner") and I don't know if he really new how to use the code-reader.

Hey I have a lot of letters behind my name and have never used one.

I meant no offense and in hind sight see it was a poor joke. I do swear though, it was just about interacting with that one person at the store. No offense intended.

Apologies.

 

[M38 Bob]

Seriously, there are some dumb bastards behind the counter at parts stores.:uhoh2:

Bob

 

[Birdman330]

Seriously, there are some dumb bastards behind the counter at parts stores.:uhoh2:

Bob

Don't get me thinking on that. -walking into the parts store- "I need x-part for a Ford 330 V8" -store counter clerk- ''Year make and model of vehicle'' -response- ''That won't help you, your computer will tell you its a 390 or 351'' -clerk looks like he's having a seizure because he can't use the computer-

I really wish I had one of Ford's real special off motors made for U-Haul only in my F350 to see if I could get them to drop dead when I went into an auto parts store.

 

[ElCheapo]

Someone should start a "deer in the headlights parts counter guy" thread!
You aught to see them when I come in with my 1981 Dodge Ram that I put a Cummins 4bt in.

As long as the motor runs, it shouldn't need replaced. It's most likely fuel or electronic related, with the possibility of a valve problem.
I would bet it's injectors. Could be a coil or two.
Never let your fuel get low, because all the crap that collects in the tank then gets pulled up into the pump, and sent through the rest of the system.

 

[TwoBobsKJ]

To the OP (not that the comments about auto parts store employees isn't hilarious - it is! :happy175 but it sounds to me like a valve rocker may have slipped off and you have one or more cylinders with no compression. Makes it tough to keep it at idle for sure.

You may need to pop a valve cover to see if a rocker is laying across a camshaft :shrug:

Bob

 

[Birdman330]

To the OP (not that the comments about auto parts store employees isn't hilarious - it is! :happy175 but it sounds to me like a valve rocker may have slipped off and you have one or more cylinders with no compression. Makes it tough to keep it at idle for sure.

You may need to pop a valve cover to see if a rocker is laying across a camshaft :shrug:

Bob

I'm going to second this opinion.

 

[Signaleer]

cynlinder #4 - report from the garage is that
1. Spark Plug broken from impact with piston - could have been from spark plug breaking first or some other cause.
2. Piston severely damaged and cylinder wall compromised.
...
185,000 miles...

The show... is over.

Replacement cost with Jasper Engines out the door - 5 to 6K multple places checked.

Gentleman... Elvis may be leaving the building..

 

[Birdman330]

Have you seen this first hand since being told or just going by what they say?

 

[Hockeygoon]

I made it to the auto-parts store and bought some oil (it was very low), and some Lucas fuel cleaner and lucas oil treatment (hoping). Oh, and I also got a tank of gas prior to adding the fuel cleaner. (Well, I added just a bit before I got my gas and then added the rest after 15.5 gallons). I also had them pull codes. The codes came back P0120 and 13 (according to the guy who I think had a high school education...)

Now, it is running, but will no idle and there is some smoke coming from the exhaust. (I honestly can't tell if it is smoke or un-burnt fuel?)



So, if I have to replace an engine on a 2002 KJ - who, where, how much? Has anyone done this and have recommendations?

Thanks,

Ed.

Any idea how long it had been driven low on oil? With all the extra noises coming from the engine and those two items it doesn't surprise me that it was diagnosed with a major failure.

Replacing the engine is a PIA unless you go with a rebuild - and then finding a decent rebuilder is another PIA. While the 3.7 is somewhat common in both the Liberty and the base Dodge pickup the problem is you are trying to find a "good" used engine that is 12-13 years old from a junk yard. Most Jeeps and pickups that old are junked with good reason. You could get what you hope is a decent one, pay to have installed only to find its worse than what you had.


Rebuilders in general are somewhat sketchy and even Jasper has its share of issues. My 100,000 mile three year warranty has turned into a PIA when the engine began to fail before it made it 3500 miles.


If you got lucky a "cheap" engine swap - used engine $500 and "know a dude" installer might swap it in for another $500-$600. But if the engine is a crap, you just threw away $1,000 -$1,100 away. Or you could get a remanufactured engine for $2500-$4000 and a shop hit you up for another $1000 to install, but most (or all) is covered by warranty.

 

[TwoBobsKJ]

Hockeygoon, I know you've had a lot of challenges with your Liberty and the engines you've had to replace, but I have to disagree on the PIA regarding putting in a replacement engine.

I swapped in an engine from an '07 Dakota and I've put over 50,000 on it since then. Yes, I had to swap out timing gears to match up with my computer but all told it cost me right at $1500 including engine, timing gears, gaskets, blah blah blah. I figure that's about 4 months of payments and insurance on a new car so I came out way ahead.

Others on here have swapped in engines from a 2012 Chrysler product with the same results - a smooth running Jeep that will last a long time.

Is a swap "easy?" No, but it isn't technically difficult. Just takes some patience, about 2 to 4 days in your garage (or a friend's) and a reasonable set of tools. The Jeep's value and ROI will be much better with a running engine than if it is just junked and sold for scrap. We do too much of that in this country as it is :emotions34:

My 2 cents...

Bob