Hey everyone-- I've started getting some engine noise and am not sure how to go about troubleshooting it (or figure out if I should troubleshoot it-- I'm scared that I'm going to run it too much with something seriously wrong and damage the engine).

Okay, so, it makes kind of a ticking sound that's not really apparent unless I'm accelerating or going uphill. It seems to get worse as the car warms up. I thought it was an engine knock (granted, i've never heard a knock in person; my only frame of reference is youtube videos), but my dad thinks it isn't. It's kind of a chck a chck a chck a.

The engine isn't performing any differently.

My oil has also started disappearing lately, but there's no smoke coming out the tailpipe.

The sound started right after an oil change.

The first and second plugs are fouling before the others. I attached a picture-- I'm a little confused about the finer points of spark plug reading. (people talk about "both sides being fouled" does that mean on either side of the gap, or that it's evenly fouled on either side of the metal horizontally? *sorry if this is a stupid question; I tend to over analyze things*).

I'm assuming my next step is to start pulling plugs-- but does this sound like something serious enough that I shouldn't be running it? (I'm scared to death it's something like a loose piston and I'm going to totally F** up the engine by fumbling through this problem myself.)

Oh, and it's a 89 4.0 with 205000 on it.

 

Looks like a head gasket may be in short order. You could try running some MMO (one bottle) or oil detergent through it (CD2 two bottles I recommend) that should take care of the tick.
The plugs your showing all look clean enough except the first one, I am assuming this is the #1, this cylinder likes to crack on the renix between the valves and can loose the gasket between the cylinders 1&2.
Not sure about the oil loss, it's got to be going somewhere; water, tailpipe, leaks???

 

A exhaust manifold leak can cause similar problem. Put a small diameter hose up to your ear and move it around engine untill nosie is loudest. At least pin point it as for oil if you just changed it, check rear of oilpan flr leak and top of air filter. Never assume just because multiple problems started at same time that they are all related. It can leave you chasing your tail.

 

Might check around the exhaust manifold too, they can make a tick-tick-tick sort of sound when they develop a crack, especially under load.
Ticking isn't normally anything to worry about with a 4.0. A dull thud thud thud deep inside the engine- that I'd worry about. I'd bet 3/4 of them out there have some sort of mild tick, normally lifter related.

What did you put in for oil & filter? No change in oil weight from previous fill?

Oil leaking anywhere?

 

Okay, sorry it took so long to reply. I really appreciate ya'lls help.

I thought I had the problem fixed-- there was a finger-nail sized hole in the exhaust pipe right around where the transmission meets the engine. However, the patch I put on there has stayed and the problem appears to be getting worse-- or maybe I've just gotten better at picking it out from the other sounds.

I would now describe it as much more of a puttering noise. It sounds almost like my engine is in a duet with a punier one. I'm pretty sure it's exhaust related-- it's rhythm pitch and cadence matches the exhaust's as it changes. I'm also picking up a slight rattle, but that might just be noise from my floorboard (I don't have any carpet).

So here are my questions:

How do I inspect the exhaust manifold for cracks? Should I remove something-- do I have to remove it? Or would it be evident enough that I could see it under the hood/ underneath?

Does anyone know if the 89s have catalytic converters? From what I understand I would presume it does, but there isn't really anything on my pipe that looks like what I've seen online.

Sorry to ask such newbie questions-- I've just never given any thought to the exhaust before.

 

Oh, also. I almost forgot. It looks like I'm just dripping oil-- god knows from where (the PO had a valve cover gasket leak that leaked about a quart every 200 miles-- and kept it that way for five years. So any new leaks really blend in).

It's only really doing it when it's hot so I didn't catch it. I'll track it down later-- I just thought I'd mention the mystery oil loss is out of the equation.

 

Una$$ those autolite plugs and use NGK ZFR5N V-Power plugs, gapped at .035"

 

Diagnose your own oil leak:




　

I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.

Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.

Many mechanics, friends, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?

A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.

First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.

Revised 9-15-2012

As Ken suggests, replace those plugs with NGKs. Replace the dizzy cap, rotor, and wires, too. Check to be sure all your intake manifold bolts are snug.

Click on the link in my signature and do the ground refreshing #1 and C101 refreshing #2.