Code P 0455 What does that mean ?

98Chero

New member
When I turn the ign on and off three times I get a code P 0455 then Done. 2002 Grand 4x4 4.0l. When engine warms up the lifters start making noise, plus oil leak out the rear main seal.
 

P0455 is a leak in evaporate system. Start with making sure the gas cap is tight. Replace it if the code does not go away.

If the code remains post changing the gas cap post back.


Are you certain it's a lifter noise not an exhaust leak? Is the oil at the correct level and correct viscosity?



Regards,
JPNinPA

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For sure the gas cap is bad, the key and locking assy came out the first time I turned it. I can buy a nerw gas cap no problem. the leak ? Im using Castrol 20-50 hard Drive or High Mileage Oil.
 
The rear main seal is known to go bad in 4.0.

The oil you are using is to high a viscosity and could result in additional engine damage.

Again are you sure the tapping isn't an exhaust leak?
Regards,
JPNinPA

Sent using TapTalk
 
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JPN I will double check that noise, I am pretty sure it a metal to metal sound tho. its not a rod or wrist pin its more like a loose rocker arm or collasped lifter or lifters. So should I change my oil to a 5w-30w or ?
 
Noise when hot -
suggest a oil pressure check with a mechanical gauge.
Use a wood rod to localize noise. One end near ear other various engine areas,
Rear seal leak - Check PCV* excess crankcase pressure will cause seal issue


* PCV AKA CCV
 

never use anything heavier than 10w40 in a street engine! heavier oils will exasperate any damage you are trying to compensate for. the heavier oils are for extremely hot heavily abused egines such as drag strip raacing engines that utilize preoilers, since the heavy oils don lubricate any better thaan greaase, and literally destroy oil seals and hydralic lifters. They also require cross drilled cranks to prevent oil starvation to the bearings, which is not done to factory engines.
 
WoW this is some really good info from all members !!! I am going to change the oil to 10-40 and replace the Mopar oil filter with a new Mopar oil filter plus get a new gas cap. I would like to point out that this jeep is hard to fill up at the pump, you really need to go slow or it pops off ? What could cause this. I really should have started a thread called Making 02 Grand RR aka Road Ready So far I have had the 4 windows fixed at a local body shop for one hours labor. It was the cable in the drivers door, I guess after so many years the cable in the drivers door just wears out, WD40 then spray greased the 2x 4x selector so it would come out of 4x4 drive. Replaced the driver side rear tail light assy with a new one because the old one had one bad screw in socket. replaced steering stabilizer and high speed balanced the front tires which stopped the DW. AC check OK Heater check OK Stereo check OK. The main bearing leak is so small that I will drive it for years before getting that fixed. All in All this is a super sweet ride, it must of been one driver highway miles only. any work that had been done must of been by a Jeep Dealership.. lots of new parts and no hooky rigs.. its a nice chage finallay
 
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New gas cap same code comes up. I did crawl under and look around the gas filler tube area and you cant see much...there is a canister type thing with hoses going in and out of it. I looked thru the gas cap area and i could see a 1/4" size hole about an inch down from the flap thing going to ?. no signs of damage to fuel/vent lines. K-2 I havnt done that rod to engine test yet. Dragen I will put some lighter wieght oil in it ( not today). JPN your always helpful Thanks All.
 
New gas cap same code comes up. I did crawl under and look around the gas filler tube area and you cant see much...there is a canister type thing with hoses going in and out of it. I looked thru the gas cap area and i could see a 1/4" size hole about an inch down from the flap thing going to ?. no signs of damage to fuel/vent lines. K-2 I havnt done that rod to engine test yet. Dragen I will put some lighter wieght oil in it ( not today). JPN your always helpful Thanks All.

Let me know if TMI -

the pump kicks off often suggest a vent valve issue AND P0455 showed a TSB that may help both


click on attachment
 

Attachments

  • tsb_wj_2500102a.pdf
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Wow typically the new gas cap fixes it. It fit properly and tight?
The gasket in the cap gets worn, damaged or dirty causing a leak. The leak doesn't allow the evap system to trigger the code.

Look for cracks in the lines or for loose fitting lines to the canister.

That hole in the filler should have a tube attached.

Filler20Neck-1.jpg



Regards,
JPNinPA

Sent using TapTalk
 
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New gas cap same code comes up. I did crawl under and look around the gas filler tube area and you cant see much...there is a canister type thing with hoses going in and out of it. I looked thru the gas cap area and i could see a 1/4" size hole about an inch down from the flap thing going to ?. no signs of damage to fuel/vent lines. K-2 I havnt done that rod to engine test yet. Dragen I will put some lighter wieght oil in it ( not today). JPN your always helpful Thanks All.

two points: first after market gascap often fail, for the price, I always buy them from a dealer to avoid chasing ghosts. Second, that canister with the hoses is another primary issue to check. there is a vacuum solenoid under the hood that goes from the engine to that cannister, check the function of the solenoid and all the hoses for leaks. You may have to drive the jeep up to 100 miles after clearing the code to ensure it is fixed.
 
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