RMSLLC
NAXJA Forum User
- Location
- Fayetteville, AR
98 XJ, 4.0, AW4, 139,000 miles
I have a pronounced Tap/knock at idle that can be heard from several feet away and even in the cabin if you turn off the radio. I changed the oil and added 15w40 Rotella (Ive heard good things about the ZDDP, etc)and a quart of lucas to hopefully quiet it down, and it seems to be slightly louder if anything!!
**On a side note, I can stick my thumb over the CCV elbow on top of the valve cover and within 10 seconds, the tap/knock goes away completely. The CCV is sucking air into the valve cover and capping it off seems to completely stop the noise. As soon as I let go of it, a rush of air goes in, and the tap/knock comes back.**
The Jeep has good oil pressure even when warm and the noise goes away when I rev the motor but comes right back as RPM's fall to idle. Laying under the motor, the noise seems slightly more pronounced but I cant seem to pinpoint it.
What is going on with my Jeep?????
I have a pronounced Tap/knock at idle that can be heard from several feet away and even in the cabin if you turn off the radio. I changed the oil and added 15w40 Rotella (Ive heard good things about the ZDDP, etc)and a quart of lucas to hopefully quiet it down, and it seems to be slightly louder if anything!!
**On a side note, I can stick my thumb over the CCV elbow on top of the valve cover and within 10 seconds, the tap/knock goes away completely. The CCV is sucking air into the valve cover and capping it off seems to completely stop the noise. As soon as I let go of it, a rush of air goes in, and the tap/knock comes back.**
The Jeep has good oil pressure even when warm and the noise goes away when I rev the motor but comes right back as RPM's fall to idle. Laying under the motor, the noise seems slightly more pronounced but I cant seem to pinpoint it.
What is going on with my Jeep?????