fastrat37

I have owned this 2004 WJ 4.7L since 2009, bought it with 76,000 miles and now we're up to 209,500 miles. All of a sudden it starts having driveability issues, engine stalls, will not restart, sits for several hours and then it cranks up and the engine runs. I have replaced all 8 spark plugs, 8 new ignition coils too when we were getting misfire codes about a 1000 miles ago. Was running just fine and now we got problems.
First, Code P0320, pointed me to the Crankshaft position sensor first since it has never been replaced, replaced it along with the Camshaft position sensor plus a new fuel pump. Seemed to be fine for a few days, then it starts doing the same thing for me tonight, drove it home from work for about an hour and just a half mile from the house the CEL comes on and the engine runs poorly, sluggish. Read the code and now there are 4 codes, P0300, P0301, P0306, P0320!! Good grief, now what the heck is wrong with this thing? Bad sensors maybe? I am stumped for now and do not want to take the crank sensor back out as it took me awhile to get it out, broke it off inside the block but got it out thanks to You Tube video.
The Crankshaft position sensor came from AutoZone and is made by "Dorman". I'm starting to think the Crank sensor is a bad part and I need to find a "known good part". Does it have to be a "Mopar" part?
Nothing better than having intermittent engine dying problems on my wife's vehicle, now she won't drive it, sure enough it happens to me FINALLY!!
Any advice would be appreciated and thanks in advance.

dave1123

Welcome to CF!

The big thing with Mopar parts is quality of construction. The Mopar CPS uses a neodymium magnet rather then a cheaper one and since this switch relies on a magnetic field to function, I'd say it's a good bet it's the one to use. Mine died at 157K miles and I now have 232K miles on it without even a peep. I ruined my Throttle position sensor by letting Seafoam get thru the shaft seal. Replaced it with Mopar, same result.

Always go with Mopar for any sensor and you'll never question the part.

fastrat37

Thanks Dave! Good advice....... That's what I am starting to think is the problem. Might as well try it and see what happens. I will post my findings as soon as I have a "no fail" condition and again thank you!

dave1123

Take care with the maintenance of that 4.7. Overheat it once and you can warp heads. Run it low on oil and you can wipe out the cam bearings. Lose a cam tensioner and jump a chain, you know what happens then.

fastrat37

The engine burns a quart every 750 miles, drivers door outside rear-view mirror went to half black, 3 water pumps, radiator replaced, power steering pump, broken exhaust studs replaced, exhaust stinks, corrosion to the max on the stock chrome spoke wheels...someone used the wrong tire machine and it was in a very salty road area for awhile before we purchased it.....the rock rails on both sides have holes the size of a nickle from corrosion, outside molding for the rear door windows have bubbling on the ends.......it's time for this thing to go down the road is what I am thinking as something major is next and I am not in the mood or cashed up to replace an engine. Stay tuned and again thanks Dave

dave1123

The exhaust stinks from the sulfur in the oil you're burning. Mine does the same thing. Most of my oil is getting into the intake manifold from the CCV system and I'm going to try an oil catch can. Google it to see what I'm talking about. I'm going to try some Caty-clean in my fuel tank to try cleaning it out. It's made by Mr Gasket and reviews are good.

My jeep was from southwestern PA when I bought it in 2012 and didn't have a single spot of rust on it then. I'm just now seeing some rust on the bottom of the doors at the pinchwelds. I've had to replace some brakelines to the rear but that's about the extent of my rust problems at present. I used cupro-nickel for the brakelines. My 0331 head cracked and my rear diff blew up but I'm keeping this WJ until I can't fix it anymore. I might buy an older XJ as a backup.

fastrat37

The new Mopar Crankshaft Position sensor is installed, cleared the P0725 code and now we will start test driving it.
I did a small experiment when I had the two sensors next to each other, the Mopar one was much stronger, the Dorman one has a weak *** magnet.
I will post an update in a few days....thanks again for the advice.

dave1123

Right! I was going to tell you I had a screwdriver stick to my new one! Mine for the 4.0 came with a cardboard spacer attached to the face to space it properly from the flexplate and it gets ripped off the first time it turns. I don't think the 4.7 needs one. The installation of mine was a trip also because it's mounted on the driver's side and the cable runs behind the block to a connector on the passenger's side. I tied a string to the connector of the old one, pulled the cable out, attached the string to the new one, and pulled it back in. I also dropped the trans crossmember and lowered the trans down for some more room to work on it.

fastrat37

The test drive went well today. No issues, no CEL, so far so good. What a pain to change it out.
I did find out this vehicle came equipped with an engine block heater! I had no idea, I tried to follow the cord up but it disappears behind the engine and I'm still looking for it, but won't need it much now I guess but still is a great option.

fastrat37

Here is an update on the newly installed Mopar CPS, it's working like it should with no issues! I have put a 150 miles or so on it commuting to work, but now the Bank 2 Sensor 2 O2 sensor is throwing the P0158 code for high voltage.
I just replaced this O2 due to damaging the original one. So I replaced it with a new one and is it possible this part is no good either?
The CEL does not illuminate in the morning drive in to work, 35 miles, but it has come on now last night and tonight's drive home about 15 miles into the 35 mile drive in heavy stop/go rush hour traffic.

dave1123

If it has CA emissions, those 02s are different from the Federal ones. Mopar gives a different part number for them and they are much more expensive. I know they have preheaters in them and sometimes they short to the sensor part. Also I've heard jeeps don't like Bosch sensors, but I have no experience with changing 02s yet on my jeep. 233K on the originals. I'm going to change one before it'll pass inspection this year. "Open heater circuit, Bank 1, sensor 1. It still gives good data, just slow to respond.

fastrat37

This O2 is a Spectra Premium OS5254 $26......purchased it from Amazon......figures. Grumble.....sensor wasn't too bad to get out, pulled a thread from the bung and the new one was hard to start into the threads. Finally got it in w/out cross-threading it.

fastrat37

Latest update...no CEL on today's 80 mile commute......19 MPG as we finally got rid of the "winter-blend" fuel and now have less ethanol for the summer.
The engine oil I used on the latest oil change is the Wal-Mart/Super-Tech full synthetic, no smoke and still kinda stinky exhaust smell. Oil consumption is not too bad as the odometer just went past 210K miles and it has not used a quart yet since the oil change at 208,700.
Stay tuned as I will update again if something else goes wrong.....I love driving it to work and back.

dave1123

Okay, here's suggestion on how to improve performance and end the stinky smell. I have never been a fan of fuel additives but I've done the research on this stuff and tried it and it works as advertised. It's called "Cataclean" and is made by Mr Gasket. I didn't even follow instructions and it worked better than I imagined it would. It tells you to put the whole bottle in with 1/4 tank and drive around 15 miles, then fill it up. I dumped the whole bottle in at the pump and filled it. The jeep started idling smoother in about 15 minutes, then after burning about 1/2 a tank it stopped stinking, was quicker on acceleration, and snappier off a stop. Then I replaced the rattling muffler with a Flowmaster 50 and there was an amazing change in my aged 4.0! I haven't had time to actually calculate it, but my VOIC says it's getting about 4 mpg better fuel mileage. I bought a 2 bottle pack from Amazon for $49.99, but I'm keeping the second bottle for a later date if this doesn't last. I'm 73 years old and the Flowmaster is about as loud as I want to go since I deliver newspapers in a residential neighborhood early in the morning and don't want to annoy the customers.

My advise is to try one bottle and see if it works for you.