Jeek KJ 2.8 CRD Limited - Advice Needed

[lobibalboa]

Hi everyone and thanks in advance for your replies!

I own an automatic 2006 Jeep KJ 2.8 CRD Limited with 65000 km on it. I am not an expert of this (or any) car so I'm just looking for some help in diagnosing some issues I've been experiencing.

First of all, I believe the TPS is quite unreliable. I've had a constant light on for a bit, and after checking every tyre's pressure it has now turned off but still flashes on periodically as I'm driving.

The second and more worrying issue is the noise that the car makes as I reach around 50 km/h. It's almost a droning sound. It sort of increases the more I speed but then can also relatively decrease over 100 km/h at times. It's quite frustrating and I don't know what to make of it.

The fuel consumption is not great (8 km/l) and I wonder if this has anything to do with the engine running cold (temperature dial barely can reach 1/4 on longer drives) and the EGR light being on.

Any advice is welcome!

 

[KJowner]

Hello and welcome.
I don't know much about the TPMS system, mine hasn't got it.
The noise could be a wheelbearing, see if its louder on one corner.
If the EGR is stuck open it will affect power and fuel consumption, the light will also come on if the system has been deliberately disconnected or blocked.
As you say running cold won't help fuel consumption, I guess you are in Europe as you are using KM, so getting a new thermostat should be easy, I use Autodoc for parts like that. I put the slightly hotter one in, an Esen SKV 88°C, good quality Polish made, avoid the Chinese ones. My Jeep does around 9.8L/100km in mixed driving.
I suggest you change the coolant when you do the thermostat unless you know it's been done recently and the correct fluid has been used, they require HOAT, no other coolant is recommended.
I had to hunt around to find suitable stuff, this was the only one I found, it needs to be mixed 50% with distilled water.

You must be registered for see images attach

 

[TURBO-DIESEL-FREAK]

Hello, lobibalboa:

I manufacture on a part time basis an upgrade serviceable engine thermostat assembly for the Jeep KJ 2.8L CRD engine. This product is called the Hot Diesel Solutions Model 001 engine thermostat assembly, and it solves all of the problems of the poorly manufactured OE part.

The Model 001 uses a commonly available bare thermostat valve that is very inexpensive to replace and gets the engine operating temperature up to 95 degrees Celsius, improving fuel economy and power production.

Please post which country you reside in. The price for my product will vary depending upon currency exchange rates and shipping costs.

​

 

[martin 2003es]

Hello, lobibalboa:

I manufacture on a part time basis an upgrade serviceable engine thermostat assembly for the Jeep KJ 2.8L CRD engine. This product is called the Hot Diesel Solutions Model 001 engine thermostat assembly, and it solves all of the problems of the poorly manufactured OE part.

The Model 001 uses a commonly available bare thermostat valve that is very inexpensive to replace and gets the engine operating temperature up to 95 degrees Celsius, improving fuel economy and power production.

Please post which country you reside in. The price for my product will vary depending upon currency exchange rates and shipping costs.

​

 

[martin 2003es]

Hi, I have a 2003 KJ RHD, engine code ENR, and live in the UK.
have the same cold running problems, please quote me for your thermostat upgrade,.
thnx martin

 

[blackhawk]

Regarding the tpms system, if it flash occasionally is due to a bad sensor. You can scan with a tpms tool and it will tell you which one is out of order. The light also flash if the sensor is in other frequency....I mean, if you replace it with a different frequency. Kj comes with 315 and 433 mhz.

 

[lobibalboa]

Hello and welcome.
I don't know much about the TPMS system, mine hasn't got it.
The noise could be a wheelbearing, see if its louder on one corner.
If the EGR is stuck open it will affect power and fuel consumption, the light will also come on if the system has been deliberately disconnected or blocked.
As you say running cold won't help fuel consumption, I guess you are in Europe as you are using KM, so getting a new thermostat should be easy, I use Autodoc for parts like that. I put the slightly hotter one in, an Esen SKV 88°C, good quality Polish made, avoid the Chinese ones. My Jeep does around 9.8L/100km in mixed driving.
I suggest you change the coolant when you do the thermostat unless you know it's been done recently and the correct fluid has been used, they require HOAT, no other coolant is recommended.
I had to hunt around to find suitable stuff, this was the only one I found, it needs to be mixed 50% with distilled water.

You must be registered for see images attach

Thank you so much for all the great advice.

I ended up having the EGR deleted so that's taken care of.

As for the droning/howling noise, upon closer inspection it seems to be coming from the differential. I'm now thinking it might be the pinion bearing that might need to be replaced. Guessing the previous owners had their fun offroading with the car.

 

[KJowner]

The diff usually howls under load and is silent when you take your foot off. Sadly if it's the diff it's time for a full set of bearings, Check the spider gears too, Mine are shot.
Jeep is going to get a set this summer if I get time, I've got an LSD to put in as well so next winter should be fun.