Nov 20, 2021 · I noticed a fair bit of oil and residue in the air box of my 98 4.0 ZJ, which starts very hard now, so I’m thinking it’s time to replace the original PCV / CCV and maybe clean my IAC. I’ve never actually replaced these before…do they just pull straight out? Do I also should replace the grommets?

Dec 28, 2007 · Most engines its PCV but for some reason on the 4.0 is called the CCV system, they are basically vacuum lines. When you need replacing you will notice oil blowback the most, around the grommets (valves on top of engine) and oil blowback on the air filter. Pop your hood and check it out.

Dec 5, 2007 · i recommend replacing the CCV + PCV + BOTH GROMMETS every 30k miles, or every time you tune=up, something like that. (grommets harden up over a short amount of time, and can cause a vacuum leak by air seeping in between the valves and grommets, as there is no longer a good seal)

Jul 14, 2008 · Starting around model year 1987 the 4.0L Jeeps used a CCV (crankcase ventilation system) instead of a PCV (positive crankcase ventilation) valve. The difference being that the CCV is a "closed" system on the Jeep 4.0L requiring two ports in the valve cover.

Apr 12, 2020 · I need to replace the front PCV/CCV valve and hose. I had removed the one end of the hose from the air box and routed that end of it below the engine because I was tired of my air filter getting full of oil. However, I was also having issues with …

Apr 3, 2023 · Jeep 4.0 LITER Crankcase Vent Problems. CJ, YJ, XJ, ZJ, WJ, TJ, 4.2, 4.0, 2.5 6cyl / 4cyl. This is a continuation of two previous videos dealing with PCV and Vacuum system issues in the Jeep 4.0.

Mopar OEM new old stock crankcase to air cleaner tube for 4.0L Jeeps, fits: 93-96 Grand Cherokee ZJ 91-95 Wrangler YJ Mopar 53006237 These are original unused factory parts. Supply is limited.

Feb 7, 2025 · OEM new old stock crankcase to air cleaner tube for 4.0L engines, compatible with Jeeps: 91-96 Cherokee XJ, 91-92 Comanche MJ, 93-96 Grand Cherokee ZJ, 91-95 Wrangler YJ. Part number 53006237. These are original unused factory parts.

Oct 11, 2008 · On another site I read a post where someone had trouble with the stock CCV setup clogging up and replaced the rear CCV hose and elbow/orifice and valve cover grommet on their 4.0 XJ with a standard PCV valve setup from a 1985 CJ7 (258 engine.)

Dec 1, 2010 · i was looking into replacing all of my CCV system, it is kinda patched together, hoses are cracking etc. im sure that the elbows are plugged up. i found this kit on ebay for a reasonable price, anyone know of a cheaper kit? see ebay link below 23+7 shipping.