I bought my '03 TJ last November and it has a "ticking" noise that seems to be coming from the intake manifold. Sometimes it is louder than others and sometimes it doesn't "tick" at all. It sounds more like a ticking noise than knocking. Recently I have had sporadic idling so I cleaned the throttle body. While that helped, it did not completely fix the problem. Then today, my check engine light came on. The codes are for both of the o2 sensors. I am going to replace the sensors tomorrow. Are all of these symptoms related? My biggest concern is the "ticking" noise....any ideas on what could be causing it? :banghead:
Info: 4.0L I6, odometer reads 85k but probably has closer to 100K because of 33's, Brute Air Intake System, Throttle Body Spacer, no other engine mods.
02-05-2011 09:26 AM
Manifold gasket maybe bad ?
Check the manifold bolts see if they are all tight ?
02-05-2011 01:58 PM
Sounds like the lifter caps. Nothing to worry about AFAIK, but you should get them sorted when you have the opportunity to do so.
02-05-2011 02:20 PM
Thanks guys...the manifold gasket was my first idea, but didn't think to do the obvious and just check the bolts...dohhhh :doh: I'm about to get under him and change those o2 sensors so I'll check the manifold bolts while I'm at it.
Lifter "Caps"...I'm not familiar with what that is. I have replaced a manifold before (in my '72 Datsun 240z...also an I6) so I may have seen them and just not know the proper name.
Appreciate the info!!
02-05-2011 02:25 PM
Cracked exhaust manifold.
02-05-2011 02:48 PM
Sorry, dunno where the CAPs came from, but as I said, have a look at the lifters. I might be entirely wrong - just had something similar going on at some stage... been a while.
02-05-2011 06:09 PM
X2 on the cracked exhaust manifold. Jeeps are prone to it. Just replaced mine last weekend. A crack upstream of an O2 sensor could very well cause it to throw a code.
02-05-2011 06:20 PM
Well, I crawled underneath and found not 2 BUT 4 oxygen sensors. So, now I'm going to go replace all 4 sensors, check the manifold bolts and check for cracks. Are cracks in the manifold usually visible?