20 Most Recent 1998 Jeep Wrangler - Page 5 Questions & Answers

Sounds like a shift position sensor problem. Will it start in neutral?

you can answer the valve question your self. just look, at the 2 hoses to the heater core. its there, or not. the 1998 is here. see cooling and HVAC sections, as i see , (no engine stated) there is no valve in the engine bay. page 7-2 , see that? then see HVAC page. if hot water flows thru the core. then the dampers are stuck (why takes tests) car has 3 vacuum servos, they can be watched to see if each works page 24-38 (chapter 24 hvac, end) in an emergancy you can force any vacuum servo to do what you want with bailing wire or tie wraps. force dampers to heat max. no recirc, and what ever direction you want. on cars with no hot water valve, (this car) they have a heat damper, yours is stuck closed. the H/C lever, moves this damper, open and closed. make it so.

skipped filters? hiccup.s can be lots of things, so tell when the hicup ,er misfire happens hot or cold engine. ? or both. at any speed. , only fast right foot?, or only wide open throttle? only on hills. ? so far , no miss at idle or slow speed.

There are several things that could cause this problem - having a Diagnostic scan and code check should be the first step. There are just too many things to check without that scan done - you could throw a lot of money at it and still be D.O.A.

This sounds like multiple things. You do have a vacuum leak, it also sounds like the EGR valve is stuck. There is no reason to be replacing thermostats that often.

Check your belts and pulleys. Belts should not be cracked and pulleys should turn freely with no noise.