JeepFreak
06-29-2013, 11:46 PM
So my '94 Jeep Cherokee Sport 4WD 4.0L 6 Cylinder has been acting up recently. The Problem: Occasionally when I get up into Overdrive gear at around 55 MPH, the Jeep hesitates to shift as if I hadn't put in enough acceleration to get it to upshift. So what it does instead is sit at just above or on 2,000 RPM's without shifting up. When I hit 60 MPH or so it finally upshifts but then when I drop back down to 55 MPH it goes back up to revving at 2,000 RPM's or just above it. I'm not sure what the problem is. My shifting is fine otherwise, no hesitation or grinding.
I took it to a tranny shop and they said the fluid was not burnt, didn't smell and wasn't all messed up inside the pan. From what they could tell without taking it apart, the tranny was in great shape. Now I should say that the people that owned the car before me had only emptied and refilled the tranny but never had it serviced (cleaning out the pan, filter and fluid) in its 20 years of existence (the manufacturer's glue was still unbroken). What I have heard of Jeeps doing when they can't find a gear is something called "Hunting". I'm not sure if anyone else has heard this but I hear it could be because the car doesn't know when it should shift because it can't detect the amount of oxygen in the fuel mixture, and thus doesn't know how much power it is actually putting out.
This would make sense since the 2 oxygen sensors in it have NEVER been changed in 20 years. I am going to replace them soon as well as the throttle position switch. Question is: has anyone ever had a similar problem and how did you fix it? What was the cause? Have you ever heard of other Jeeps "hunting" or has yours done it before? Any help no matter how big would be appreciated.
I took it to a tranny shop and they said the fluid was not burnt, didn't smell and wasn't all messed up inside the pan. From what they could tell without taking it apart, the tranny was in great shape. Now I should say that the people that owned the car before me had only emptied and refilled the tranny but never had it serviced (cleaning out the pan, filter and fluid) in its 20 years of existence (the manufacturer's glue was still unbroken). What I have heard of Jeeps doing when they can't find a gear is something called "Hunting". I'm not sure if anyone else has heard this but I hear it could be because the car doesn't know when it should shift because it can't detect the amount of oxygen in the fuel mixture, and thus doesn't know how much power it is actually putting out.
This would make sense since the 2 oxygen sensors in it have NEVER been changed in 20 years. I am going to replace them soon as well as the throttle position switch. Question is: has anyone ever had a similar problem and how did you fix it? What was the cause? Have you ever heard of other Jeeps "hunting" or has yours done it before? Any help no matter how big would be appreciated.