Kj Jeep Cherokee Issues

[glennmreid]

I'm hoping someone who is a mechanic, particularly some who have knowledge of turbo diesel motors can help me. I have a 2005 Jeep Cherokee Kj series, turbo diesel. The malfunction light came on the dash, followed by a loss of power. It was like driving without a turbo. Very sluggish. After doing some research, I found out how to do a test to get the OBD-II code. The OBD-II code I get is P0299. I know this is something to do with the turbo. Can anyone provide me information about the specific problem?

[IWANNABROCK]

Does this engine have a waste gate on the turbo? maybe manifold pressure line from inlet manifold to wastegate has a hole.or your wastegate actuator could be leaking,wastegate butterfly, if internal could be cracked were it seat's.do you have an intercooler? maybe cracked or boost hose split. is there any unusual whistling sound? any black smoke?

[glennmreid]

Does this engine have a waste gate on the turbo? maybe manifold pressure line from inlet manifold to wastegate has a hole.or your wastegate actuator could be leaking,wastegate butterfly, if internal could be cracked were it seat's.do you have an intercooler? maybe cracked or boost hose split. is there any unusual whistling sound? any black smoke?

Not sure what a waste gate is. It does have an intercooler. What we did notice was under acceleration, there is a sound under the jeep like an air sucking noise. I was thinking maybe a split hose of something, and this would reduce the boost pressure to the turbo.Not sure really. There isn't and smoke.

[IWANNABROCK]

Not sure what a waste gate is. It does have an intercooler. What we did notice was under acceleration, there is a sound under the jeep like an air sucking noise. I was thinking maybe a split hose of something, and this would reduce the boost pressure to the turbo.Not sure really. There isn't and smoke.

I would get your hoses which go from the turbo to intercooler then to inlet manifold checked,this is a simple pressure test which any shop set up for turbo vehicles should be able to perform, this will let the boost air escape instead of pressurising inlet manifold thus making it feel like no turbo. a waste gate is what controls boost pressure,can be air operated from inlet manifold pressure, , most car engines are electronicaly controlled.

Edited May 11, 2008 by IWANNAJEWY

[micksfishn]

my advise is take it back to jeep get a pro to look at they have the right tools cars are worse then computers these days get it fixed properly the first time so it dont let u down again

[dangles]

my advise is take it back to jeep get a pro to look at they have the right tools cars are worse then computers these days get it fixed properly the first time so it dont let u down again

i used to work for nepean motor group who do jeep servicing. From the web dtc 299 is a low boost signal to the computer. Could be a number of things but if you can hear an air type noise under load, this would be the boost pressure leaking out causing the manifold air pressure to be lower than what it should be throwing the code and causing the vehicle to go into limp home mode. check all the hose clamps on the intercooler piping from turbo to manifold to make sure they are tight. The clamps are common to work there way loose. Cant remember how to clear the codes.

The reason why a diesel will go into limp home mode when underboost is because they are a lean burn engine. They cannot compensate for not knowing what boost is being pumped into the cylinders to ensure overfueling doesnt occur which will end up melting pistons

hope this helps

[glennmreid]

Thanks guys. Pretty much answers my query. I suspected an air leak in the turbo region, and the motor has gone into limp mode. Will give an update when it is fixed.

[Reefking]

I'm hoping someone who is a mechanic, particularly some who have knowledge of turbo diesel motors can help me. I have a 2005 Jeep Cherokee Kj series, turbo diesel. The malfunction light came on the dash, followed by a loss of power. It was like driving without a turbo. Very sluggish. After doing some research, I found out how to do a test to get the OBD-II code. The OBD-II code I get is P0299. I know this is something to do with the turbo. Can anyone provide me information about the specific problem?

G'day mate the fault code is as follows...P0299 - Boost Pressure Sensor Positive Deviation, or basically its leaking boost could be as some others mentioned leaking hoses or waste gate is stuck open , which basically lets all the exhaust gases escape from the exhaust side of the impeller and creates lack of boost from lack of impeller spin...hope that makes sense.

I to have a 06 KJ and have had nothin but drama's I am not very impressed with this vehicle so far or their lack of urgency in fixing my concerns.

Reefking

[dangles]

G'day mate the fault code is as follows...P0299 - Boost Pressure Sensor Positive Deviation, or basically its leaking boost could be as some others mentioned leaking hoses or waste gate is stuck open , which basically lets all the exhaust gases escape from the exhaust side of the impeller and creates lack of boost from lack of impeller spin...hope that makes sense.

I to have a 06 KJ and have had nothin but drama's I am not very impressed with this vehicle so far or their lack of urgency in fixing my concerns.

Reefking

Reefking from my time working on jeep/chrysler they have massive electrical problems. Also parts supply can be somewhat non-existant at times. I copped so much abuse from 1 customer after they saw me working on their vehicle which we could not fix due to parts. 3 tries to get the right parts to fix it. Sometimes its not the dealers fault, however Head office should be stepping in and fixing up the parts supply issues