Question to all you Jeep Experts?

[Andrew Mac]

There is no change between AC on or AC off at idle.
I just got back in town and will be jumping into this issue/project tomorrow.
Have the new fan to install, 195 thermostat, Mopar Water Pump, replacement temp sensor, and a bunch of other items.
I'll keep you posted.
Thank you!

 

[Gennybro]

Well , We all want to know how many curse words is gonna fly. Thoughts count .

 

[JPNinPA]

Hope it goes well! That is where you should idle 750rpm.


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[JPNinPA]

Progress?


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[Andrew Mac]

I will be tearing into the project Tuesday. I have been prepping everything before hand. (painting thermostat cover, water pump )
installed new temp probe into new thermostat housing.
Will be installing new fuel rail modified with fitting for fuel pressure line.




Adding this instrument cluster as well. Will be adding a large capacity Transmission sump cover with a temp probe. As well as a hard line engine oil pressure gauge.



Have installed this 60mm Throttle Body Spacer. Will be installing Harland Sharpe Roller Rockers, P/N: S40196 this week as well along with the new Flex - A - Light Fan

Will keep you posted,
Thanks for the input!
Andrew~

 

[JPNinPA]

Return the TB spacer. It does nothing


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[bexer83002]

Return the TB spacer. It does nothing


Never look down on anyone unless you are helping them up - Jesse Jackson

Nice

Sent from my SM-G965U using Tapatalk

 

[JPNinPA]

Nice

Sent from my SM-G965U using Tapatalk

Just being honest. In 05 I bought one. Did nothing for the 4.0 engine. There are several threads and dyno research on this.
While it still could be returned, I recommend that and spend money elsewhere.
The extra wide makes no difference because the intake opening is smaller and the TB opening is smaller and tapered.

Same doesn’t apply to carbureted engines.

 

[Andrew Mac]

Here's the RPM at 65 mph!

 

[JPNinPA]

So if i calculated and looked the correct info up , you have stock gears and trans with 35 in tires and corrected speedo gear. Correct?

That makes it hard to maintain 4th gear and pass at 65 mph. It also lugs the engine. This will add heat as it likely is lean and kicks down to lower gear to speed up.
But your bigger issue is getting heat out.
As noted earlier clear path for air to flow through the radiator, 195 deg thermo, stock radiator, and greater than 2700 cfm fan.


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[Andrew Mac]

33" tires, stock gearing, corrected speedo gear.
Have installed the 195 thermostat, Flex - A - Lite fan, Mopar water pump, Mopar radiator, Mopar thermostat housing, Mopar temp sensor.
Running around town temp is running just below 210 indicated. lower than it was with the 205 degree thermostat. Fan cycling on and off normally.
Removed the Throttle Body spacer.
The fuel pressure is running ~50 PSI at all power settings. Normal.

 

[Andrew Mac]

What is your recommendation for the best spark plug for the 2004 TJ 4.0?

 

[JPNinPA]

dual-tipped platinum plugs including the Autolite APP985 and Champion 7412

Iridium is $$$
Copper or single platinum wear out fast and cause issues.
All other are gimmicks. Vpower E power…

Fuel pressure looks good.
I change plugs 30k miles and clean TB and IAC. Check and clean battery terminals and grounds body and engine side all at same time.
Never look down on anyone unless you are helping them up - Jesse Jackson

 

[JPNinPA]

PS it sounds like you fixed the overheat/hot issue.


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[Andrew Mac]

Will not know if the temp issue is resolved until I get down the highway a while. The issue did not manifest itself until I was highway speeds for hour +. Will do that next couple days.

 

[Andrew Mac]

The over temp issue seams to be in check!
The Jeep seams to be not producing normal power.
I'm still chasing potential issues. As I noted, I've added a hard line oil pressure gauge. When the engine has warmed up, the pressure drops to below 10 psi at idle. I have a high volume pump to install this week. While I have to Oil Pan removed I will check the main and rod bearings as well as the timing chain assembly.

Compressions are as follows:
#1. 150
#2. 140
#3. 145
#4. 150
#5. 150
#6. 150

I think I will be ultimately be removing the head. I have a small coolant leak someplace on the drivers side of the engine buried under the manifolds. No evidence of coolant in the oil, or oil in the coolant. I guess I can pressurize the coolant system and look/listen for the leak?

Question? what's a good way to check Catalytic Converter health? 12+ years ago I got a load of bad gas that destroyed the Cats. At that time the Jeep lost power as well. Is there a good way to inspect them or test them?

 

[superj]

i think you have to put it on a machine to check the cats. not 100% sure, but i think. i have never heard of another way

 

[JPNinPA]

Pressure test and leak down test the radiator. You coukd leakdown test the cylinders.
Factory spec for compression is150 +/- 15. Anything under 130 can be an issue.

The spec for oil pressure for the 4.0 is as follows:

*Not less than 13 psi at HOT idle
*Between 37-75 psi over 1600 rpms

So on#3 do both a dry compression and wet compression test. That will show you if it is the piston rings or a valve.
The things I look at are easy. Air filter. What did your spark plugs look like?? Pics esp #3. Clean TB and IAC. Clean battery connections and the opposite end of the grounds. At the engine and body.
Run some fuel injector cleaner. Run the engine above 3300 rpm for a bit so the valves may move and keep carbon from building up.
Run seafoam or mist water to clean carbon.
What type of gas?? If it has high ethanol you get poorer mpg.
What mpg do you get now?
There is a app pure gas will show stations with no ethanol gas.

How is your transmission fluid?

Any vacuum or exhaust leaks?

Tires all st proper pressure?

Load: what junk is in your trunk?

There are two methods to check CATs.
Before this any Check engine codes?
First mentioned above is a OBDII system that can read O2 sensor info. There you validate the timing of the sensors. Pre CAT should be different from post CAT.
The second is physical. Knock on the cat and listen for anything rolling around. Broken CAT might sound like a loose stone in there. Hollow is just that. The last is temperature. When the vehicle is at temp the front of the CAT should be.200 temp compared to the exit of the CAT app 400 deg

Being this is a 2004 check your OPDA for wear. If a real issue you get screaming monkeys or CEL for CKP snd CPS out of sync

What oil filter brand do you use?


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[Andrew Mac]

I run 30 psi in all four tires. All are good.
I run. NAPA Gold 1515 oil filter, its got less than 1000 miles on it.
Mobil One high milage oil, less then 1000 miles
Just drained and serviced transmission with Mopar ATF-4 oil. The oil that drained from the transmission was dark. It only has about four thousand miles on it. Definitely not normal.
I keep the Jeep pretty empty of "stuff"! Weight is not an issue.
Removed spark plugs. The ones I removed all look good. less than 1000 miles on them, installed New.
The OPDA has less than four thousand miles on it.
Fuel Injectors are new, aftermarket. 4 port.
The TB is clean, as are all the associated bits.

The engine idles smooth. it's very quiet with the Harland Sharp Roller Rockers.
Standing beside the running engine with the hood open, it's quiet and normal. No ticks, no knocks, nothing abnormal.
When you move around and sit inside, there is a prominent knock! Maybe a transmission valve? Oil Pump?
Even after a detailed check with a stethoscope, nothing abnormal can be heard from the engine/transmission.
When I have the oil pan dropped I will check the Rod and Main Bearings for health. I have replacements in the ready!

 

[JPNinPA]

Plugs can show if you are burning rich, oil, or water. That is why I asked.
From the top the 3rd and 6 th are a bit sooty on the outside. Not on the ceramic.
So #3 is not burning water. If it were it would be steam clean.


If you can’t hear the knock from the engine bay it is not the engine. It could be the bell housing to top of the trans.
Maybe the torque converter. I could hear my throwout bearing from inside but not outside the vehicle.


Never look down on anyone unless you are helping them up - Jesse Jackson