I have a 1998 ford ranger 4.0L with about 280,000. I use it as an extra vehicle so it doesn’t get a lot of everyday driving. I replaced the upper and lower intake gaskets about 7 years and 35,000 miles ago. That took care of a chronic lean bank 1 and 2 code. Lately the truck started idling rough and being a little jerky after it was first started. It would generally get better after it had warmed up and was usually worse when starting on a very humid or rainy day as well as when it was cold out. Then the truck started getting a flickering CEL. I ran FORScan light on it today and the lean bank 1&2 codes are back as well as a misfire on cylinders 1&5. I didn’t have good records of the last time I did tune up stuff so I started with coil pack, new plugs, new fuel filter and cleaned the MAF. When I started it back up there was a noticeable improvement in the way it was running but CEL was still on. I’ll probably reset it tomorrow and see what it does. While I was looking around for signs of a vacuum leak I noticed the large vacuum hose was very brittle and collapsed under the vacuum. It comes from the intake and connects to a plastic elbow then another hose to the Evap canister that mounts on the drivers fender. Wasnt sure if anyone would have a part number for that hose. I guess I could match up a similar sized hose but it looks to have some premade bends in it. Also wondering if those gaskets could be bad again? Any thoughts on what direction I should go next?