Ok, let's play a game of guess the pending problem...

We have a 1998 cherokee sport, 4 wheel drive, 4.0. 184,000 on the odo.

I have changed the fluid in the transfer case, but due to laziness have not changed the fluid in the pumpkin or the trans. The fluid in the trans is nice and pink, proper level, doesn't drop prematurely, and doesn't seem to be an issue. The pumpkin, for the time being is a unknown factor. It doesn't seem to be a problem, or have any issues or symptoms... it appears within normal limits.

My issue, with the weather getting cooler in detroit, I have had 2 separate occurances of my check engine light coming on, and my tranny not wanting to shift into overdrive when over 50 like it's supposed to. Even to 70 or above, the trans won't shift. It doesn't seem to be a hard shifting issue, just not at all. And yes, I have tried running in drive, the upshiftng, to no vail. It runs in drive ok. Then the light goes off, and no issue.
Any help is, as always, appreciated. Thanks in advance.

 

Ps.

When the light goes off, it is after it sits for a few hours, and I restart it.

I have tried turnin it off, waiting a few minutes and tuning it back on. Generally the light stays on.

the next day. No light.

This issue seems to be separate of engine temp and outside temp. There seems to be no coorelation.

Now, no light for the last week.

I would prefer not to break down when it snows, and fix the pending issue now.

Thanks.