Two issues crept up after my last off roading adventure. I didn't go anywhere too rough, just some trail riding after the rain. First problem, when I start the jeep, hot or cold, it runs up to 1500-1800 rpms and sits there for about 5-10 minutes before it finally goes back down to regular idle. I've gone over every vacuum line and intake seal with no luck. Second, I'm tearing up u-joints again. The rear driveshaft joint keeps falling apart and it's only on the ends that have the bolt down straps. They seem tight when I put them in, but they loosen up horribly whether I'm offroading or just daily driving. I'm stabbing at the obvious answer, but should replacing the straps fix this problem?