What’s now?

[Mcnenc1]

Just bought a 2004 Jeep TJ 141k miles. For $9k

Known issues:
1) P0300 random miss fire
P0303 cylinder fire
P0304 cylinder fire
So I’m guessing replacing the spark plugs and coil would fix that?

2)oil pressure gauge drops to “0” when idle say at a stop light or in traffic. Lights and noises come on saying “check gauges” in red?
I was told to replace the oil sending unit or oil pump OR just a less thicker oil like 15W??

3)when driving it sounds like the suspension is “creaking” but slightly and only when going over a hill, slows bump, etc?
Could this be a dried rubber bushing or could it be a bigger issue?? How would I be able to dictate that?

The engine itself is in great shape! And has been garage kept the last few years and towed for almost HALF it’s miles! It’s a great Jeep just some normal maintenance issues. No big deal. However, I plan to knock all these out in one or two days at local mechanic that I’ve been going to recently and he’s awesome! Insanely low priced and opened his shop as a “hobby”. But this isn’t why I bought the Jeep. I bought it to work on it myself and her know every bolt on it however I really don’t want mess anything up on it mechanically because this is my daily driver. What’s your take on this?

Anyways, these are the only three things I feel the need to fix immediately but what about after?? What’s my next project and why should it be that?

Thanks I’m advance for the replies!

*** EDIT// my idea for the TJ is to be able to take it cross country and road trips as comfortably as possible and reliably. But, be able to go to the beach on weekends and drive it to the mountains and do some light trailing too.

Goal = well centered Jeep that’s capable in all environments including the highway









What now?

 

[064banger]

I had the same codes but was also experiencing major misfiring. I replaced the ignition coil, plugs and wires and that fixed it.

I would also start with the oil pressure sending unit. Mine does the same thing now but its very intermittent. I haven't replaced mine yet so can't guarantee that will fix it, plus it could be your oil pump.

Do you have the 2.4 or 4.0? If it's the 2.4 I made a video on replacing the ignition coil, it's relatively easy and a great way to start learning about your Wrangler.

Congrats on your purchase btw.

 

[Mcnenc1]

Awesome thanks for the fast reply! Yea so it misfired one time, didn’t even notice tbh, and the check engine came on it, ran it, and those codes appeared. I replaced the gas cap with an OEM part and now the check engine light is off with no misfires? Idk it’s kinda weird.
It’s a 4.0l

Thanks!

 

[064banger]

Yep that is weird. However in my experience with my misfire issue my CEL would also turn off and the issue would go away for a while, only to return a few days later.

It turns out my ignition coil was on on its last legs, but I guess there were times it would run fine and not trip any codes. When I pulled the plugs they were fine and had normal wear (according to the pictures I looked at).

You may want to look at your plugs first. Especially on cylinders 3 and 4 and compare them with pictures of different types of plugs wear, or post them on here and get people's opinions.

 

[Mcnenc1]

I’ll do just that I’ll post them here

 

[mrblaine]

The engine itself is in great shape! And has been garage kept the last few years and towed for almost HALF it’s miles!

Common misconception that I see mentioned all the time but it will have been driven every single mile you see on the odometer. When it is towed, it is done with the key in the unlock but off position which means the vehicle is dead electrically. If it is dead electrically, there is no way for it to record the miles registered by the speed sensor in the t-case.

 

[skrelnik]

[

Just bought a 2004 Jeep TJ 141k miles. For $9k

Known issues:
1) P0300 random miss fire
P0303 cylinder fire
P0304 cylinder fire
So I’m guessing replacing the spark plugs and coil would fix that?

2)oil pressure gauge drops to “0” when idle say at a stop light or in traffic. Lights and noises come on saying “check gauges” in red?
I was told to replace the oil sending unit or oil pump OR just a less thicker oil like 15W??

3)when driving it sounds like the suspension is “creaking” but slightly and only when going over a hill, slows bump, etc?
Could this be a dried rubber bushing or could it be a bigger issue?? How would I be able to dictate that?

The engine itself is in great shape! And has been garage kept the last few years and towed for almost HALF it’s miles! It’s a great Jeep just some normal maintenance issues. No big deal. However, I plan to knock all these out in one or two days at local mechanic that I’ve been going to recently and he’s awesome! Insanely low priced and opened his shop as a “hobby”. But this isn’t why I bought the Jeep. I bought it to work on it myself and her know every bolt on it however I really don’t want mess anything up on it mechanically because this is my daily driver. What’s your take on this?

Anyways, these are the only three things I feel the need to fix immediately but what about after?? What’s my next project and why should it be that?

Thanks I’m advance for the replies!

*** EDIT// my idea for the TJ is to be able to take it cross country and road trips as comfortably as possible and reliably. But, be able to go to the beach on weekends and drive it to the mountains and do some light trailing too.

Goal = well centered Jeep that’s capable in all environments including the highway

What now?

Welcome aboard! Post some pics of the Jeep.

1) Spark plug change would be an easy maintenance item to see if it solves these codes. Autolite XP985 are a great choice.

If you suspect the coil rails, the Mopar replacement is pricey so I would replace the plugs first, if the problem is still there test the coil rail. Here is a YouTube video to do a test.

2) Yeah, I have read that the sending unit can fail and should be replaced. Mopars part is like $30 and I highly recommend Mopar parts for these cases.

What oil is in your Jeep, perhaps and oil change to 10w-30. Oil is a super sensitive subject but the Jeeps can handle conventional, semi-syn and full sun. Personal choice but stick to 10w-30. Personally I use Pennnzoil high mileage full synthetic and get it from Advance Auto when it goes on sale. Filters I generally use Mopar unless Advance Auto has a sale when you get a free or reduced price Purolator Boss - PBL14670.

3) Can you pinpoint this creek to a specific area, like passenger side front by shock?

4) Depending on your lift size, budget, and skillset, would determine this. I put an OME kit on and love it on road and off road in dirt, mud, off camber trails.

I ordered the kit from Dirk at DPG Offroad and did the install myself.

If you are a novice, like me, this is a good route. If you are more mechanically advanced then you could piece it together and save a couple bucks.

 

[Mcnenc1]

Common misconception that I see mentioned all the time but it will have been driven every single mile you see on the odometer. When it is towed, it is done with the key in the unlock but off position which means the vehicle is dead electrically. If it is dead electrically, there is no way for it to record the miles registered by the speed sensor in the t-case.

Wow. I had no idea. Thanks for that seriously! I wish I would’ve known this before buying it may of helped out in the long run..