The reason I'm asking about the tach is I want to know how high you rev the engine.

Ever go over 3,000 RPM?

I'll keep an eye on it.
I'm about to head out so I'll see what it's looking like.
I took it to a shop and they told me everything was testing fine and it was the coil pack so I just bought one myself and changed it. Felt better for a day and then engine light back on and running shakey again.

The coolant is not getting into the oil, it's getting into the cylinder(s).

If it's a head problem.

If it gets into the oil, that is very bad for the bearings.

I sure hate to see people to throw unneeded parts and labor at something without actually fixing the problem.

I hope you didn't pay for a diagnostic at that shop that told you wrong. If you did, see if they will refund the fee and pay for the coil pack.

Never really gets past 3000 rpm. I can make if I floor it but even still once it switches gear it's right back to two thousand.

Out of curiosity, what is on your mind about the RPM? Would constantly going over 3k cause a problem, or never going over 3k cause a problem?

As far as the issue at hand,
My money would on the head with a little coolant into the cylinders in this situation. Does your exhaust smell sweet? White colored? Lose coolant a little bit at a time? I only ask because my head cracked at 162k. Oil was not milky, car ran great, coolant was the correct color and not all that bad. Only lost ~pint of coolant a month. Then I found the just over 3" crack on the head.

They had a problem with the exhaust valves not rotating on 4.0s that were rarely revved over 3000 RPM. Carbon built up under the exhaust valve. also had an issue with weak valve springs.

The heads crack between cylinders #3 and #4 and do not leak into the combustion chamber, but into the valve cover area.

My suggestion. Follow the instructions with the 44K. Run the crap out of it. Won't hurt it a bit. It is NOT a tractor engine. Never was.

wouldn't be hard to diagnose a misfire if you could check the coil with a scope.

Thanks guys. I'll try all this out and take a better look between the two coils for a crack.

Don't have any smoke coming out the muffler.

Really appreciate all the help. There's a few other issues I have going on but this is the most important. I'll be sure to start other threads when the time comes.

Isn't that what the PCM is doing?

PCM can't scope the ignition.

How then does the PCM determine there's a misfire?

What is it reading?

crank sensor speed, i imagine you know what a graphed crank sensor looks like, right?

Explain that please

Cruiser beat me to it. I recall quite some time ago reading about the valve problems and carbon build up causing problems. I also seem to recall that for whatever reason, it can often effect the first two cylinders more than others. Not sure why.

A compression test is where I would start. And if you have a significantly lower reading on cylinder #1 (like 15% or more lower than the average of the others), I'd say Cruiser's assessment of valve issues is probably on target.

Engine cleaner may just do the trick. My brother, who has been a mechanic for years, swears by Seafoam. I've never used it myslef. Back in the old days before fancy sensors, catalytic converters, and computer management, we used to put a quart of ATF in the engine and drive it that way for a tank or two to loosen stuff up and clean it out, then drain it all out and refill with clean oil. Of course, compared to now, gas and oil back in the old days was crap, and engine sludge was just a fact of life.

Most times the compression test won't reveal the issue.

It's like a "running" misfire with only a slight loss of compression.

A buddy of mine fought his for a while and finally got rid of it using water.

For now, 44K and some high revving will probably help.