management light

joohn · **Posted:** Wed Mar 16, 2016 5:34 am

I have 05 2.8 CDR limited,
I have owned the Jeep for 14 months now, my driving is not aggressive I rarely reach 2.500 rpm when driving, I have a problem with the engine management light. Normally the temperature gauge stops below the 1/4 mark, but now and then the temp rises to 2/3 across the scale and with a ding the light comes on. I cant get the temp down with steady driving, it seems to stay hotter than normal.

I have checked the water and oils, but nothing seems wrong, the cure is simple, go for 2 short drives about 5 miles turning the engine off each time then on the third time the light will be off permanently and the temperature will be back to normal. I can get the management light to come on with aggressive driving (showing off with the wheels spinning) again after it comes on 3 slower trips put it out.

Any ideas what is bringing on the light? could it be the O2 sensor in the exhaust?

john

Mountainman · **Posted:** Wed Mar 16, 2016 10:55 am

No O2 sensors on your diesel. Sticking thermostat or bad temp sender or its wiring? I'd check the connection, they like to get fried if the exhaust shield isn't in place.

Probably sticky thermostat though is my guess.

olypopper · **Posted:** Wed Mar 16, 2016 11:14 am

Hook up your jeep to a diagnostic scanner and post the codes here.

joohn · **Posted:** Thu Mar 17, 2016 2:41 pm

Is it possible to get the codes out without a diagnostic scanner, I could do that with my Toyota? I think I have found the over heating mu rad was blocked with farm mud from the muddy tracks I washed the dirt out with a hose pipe and the temperature is OK now, just leaves the engine managements light that lights on now and then.

joohn · **Posted:** Fri Mar 18, 2016 5:07 am

The EM light has come on again and the performance is poor must be in limp mode, I have checked the oils and waters and it sounds good, the overheating if fixed just the mud splattered up the rad.

I will look into getting the codes out of the CPU but there must be a way to do it without the workshop hookup?

flash7210 · **Posted:** Fri Mar 18, 2016 9:04 am

Buy your own scan tool.
Some are cheap and some are very expensive.
But all have some limitations with the types of codes they can read.

If you already have a Android phone or tablet then I recommend getting a ELM327 bluetooth adapter and then buy the TorquePro app.
Or buy the Actron CP9125 PocketScan Code Reader.
Both are available through Amazon.com

For me, the TorquePro app has been a valuable tool for diagnostics.

wilco549 · **Posted:** Fri Mar 18, 2016 4:43 pm

joohn wrote:

The EM light has come on again and the performance is poor must be in limp mode, I have checked the oils and waters and it sounds good, the overheating if fixed just the mud splattered up the rad.

I will look into getting the codes out of the CPU but there must be a way to do it without the workshop hookup?

Most auto parts stores will read the codes and provide a print-out for free. Try Advance auto, autozone or O'reilly.

papaindigo · **Posted:** Fri Mar 18, 2016 5:26 pm

Folks - look at the signature the OP has a "Cherokee" not a "Liberty" hence is not in the US or Canada so Autozone, etc are not options even if their scanners work which they often don't.

That said there is a "key" trick that often works to pull codes on the 05 model although sometimes it swaps the last 2 digits. Suggest you PM or email Billwill as he also has a Cherokee and is reasonably knowledgeable as I don't know the details of the key trick.

joohn · **Posted:** Fri Mar 25, 2016 12:48 pm

I have sent for a fault reader so answers soon I hope as the light comes on after about 6 trips then off for a while.

joohn · **Posted:** Tue Apr 05, 2016 10:18 am

I purchased a plug code reader but they will not work with a i phone only android ones. so I found a neat bit of kit a MaxiScan ms309 it comes with a lead and a screen.

I plugged it in and turned on the ignition it worked immediately telling me I had one fault "turbo over pressure" I assume there is a wast gate somewhere that is stuck or is it something else? any ideas?

john

flash7210 · **Posted:** Tue Apr 05, 2016 11:57 am

joohn wrote:

I plugged it in and turned on the ignition it worked immediately telling me I had one fault "turbo over pressure" I assume there is a wast gate somewhere that is stuck or is it something else? any ideas?

john

Could be the MAP sensor needs cleaning.
Could be one of the boost control solenoids is bad.
Could be the vanes in the turbo are stuck.

I'd start with the MAP sensor.

joohn · **Posted:** Tue Apr 05, 2016 2:30 pm

any posts on how to do that? I am not sure what a MAP sensor is.

I am unfamiliar with the 2.8 engine I am good at fixing things when I understand what is wrong.

thanks for the reply I will research it a bit now.

john

papaindigo · **Posted:** Tue Apr 05, 2016 2:55 pm

Take a look at Sir Sam's NOOB guide at the top of the page. Lots of good information although the location of stuff may be a bit different between left and right hand drive vehicles but probably not on the engine block.

joohn · **Posted:** Wed Apr 06, 2016 2:39 am

Thanks looking at the MAP sensor today and cleaning it, also changing the air filter missed that on the last service.

I will come back with details soon.

john

joohn · **Posted:** Wed Apr 06, 2016 10:13 am

An easy job needed a large wedge to lift the cables gently out of the way, using a 4mm allen key it was easy to remove the MAP sensor, the sensor was compleatly jamed up with small bits of matter held in with oil and crap, I used break fluid and a soft artistes brush to soften and remove all the mess, I was surprised at the amount of rubbish I removed, I dried it off with a tissue and re fitted it. I will wait and see if I get the EM light again this week.

It,s a big thank you for the input that helps newcomers to this forum sort out there Jeeps, thanks friends.

joohn · **Posted:** Fri Apr 08, 2016 6:15 am

Well all was fine for a short time then on comes the EM light, I read the codes again and there is one fault "Turbo charger / Supper charger over boost condition" I have not pushed the Jeep since I cleared the last fault code, revs not been over 2.500 rpm at any time and no hard work.
It must be am waist gate fault causing the over boost, I will try to find entries on this and learn how the 2.8 engine sets boost pressures. but any help I would be gratefully for.

john

papaindigo · **Posted:** Fri Apr 08, 2016 10:12 am

The CRD turbo does not have a waste gate as it's a variable vane turbo. Sticky vanes can cause boost issues depending on what position they are stuck in. To check vane function per GDE at idle in park. Underneath the vacuum actuator on the turbo is rod extending downward connected to the vane mechanism. If you pull off the vacuum line at the turbo, the arm should drop about 1/2 inch and then raise back up after reconnecting the vacuum line. It is a bit difficult to see the rod, but this is the easiest method to check for proper VGT vane movement.

There are several methods to unstick the vanes but the first one to try is the Ialian tuneup - get the engine up to operating temp and then do several full throttle acceleration runs up a minor grade such as an Interstate on ramp. Should burn of the soot that causes the vanes to stick.

WWDiesel · **Posted:** Fri Apr 08, 2016 3:44 pm

It still could be a bad map sensor, I would replace the map sensor with a new one and see if cures the problem.... :wink:

joohn · **Posted:** Sat Apr 09, 2016 10:29 am

The strange thing is it's going like an express train now pull hard in the lower revs 30% more performance, a real big change so cleaning the Map has done a positive thing, I have looked at the cost of a new MAP sensor its around £36 including post is there any cheaper in the US?

I will disable the exhaust to intake valve tomorrow, and take out the MAP valve to see how it looks now. I will try to determine if the rod is moving that shows the vains on the turbo are working.

Billwill · **Posted:** Sun Apr 10, 2016 5:01 am

The Export 2005 2.8 CRD is virtually the same as the USA models..ie has a variable vane turbo and no wastegate....apparently some difference in the EGR system according to glend from Australia.. www.ausjeepoffroad.com/forum/

The "Key" trick should work on a 2005...turn ignition ON/OFF rapidly 4 times without starting...forth time leave ignition ON. :wink:

management light

Who is online