cherokee auto wont shift until 3500+ RPM

1990 cherokee 4x4 4.0 aw4 tranny. Most of the time the tranny wont shift from first to second or second to third or third to OD until my RPMs have gone above above 3500. This happens even at very low throttle. I'll be driving down the street @ 45 mph and the engine will be revving @ a little over 3k rpm. Its not that bad of a problem but it annoys the hell out of me when things dont work how theyre supposed to. Plus Im wasting so much gas driving around town in second gear. What components may need adjustment or replacement and where would these components be located? Any help would be appreciated. [email protected]

I wish I had that problem!!

Have you changed fluid lately? never heard of a problem like that, it's usually the opposite.

Sounds like the TVS cable may need tightening. It's on the side of the Throttle body.

Or could have something to do with the throttle position sensor going bad? Had any work done to your xj/ anyone under the hood/ oil change etc. around the time you noticed the problem? Would start with adjusting the kickdown cable and checking to make sure it slides smooth, only supposed to move an inch or so, IIRC...might out to check out the chilton/haynes manual at the library for directions on how to do that...

Mine did the same thing. It sounds exactly like the TPS. To check it slide a T-pin for cork boards next to the wires on the back of the connector the voltage should read about .6v at idle to 5v at WOT. I did not think the TPS had anything to do with the tranny shifting, but it did. You can also check the codes by rolling the key three times and counting the flashes of the check engine light, because the tps should throw a code.

jeep1947 said:

Mine did the same thing. It sounds exactly like the TPS. To check it slide a T-pin for cork boards next to the wires on the back of the connector the voltage should read about .6v at idle to 5v at WOT. I did not think the TPS had anything to do with the tranny shifting, but it did. You can also check the codes by rolling the key three times and counting the flashes of the check engine light, because the tps should throw a code.

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Don't do the test with the engine running.

The '90 won't give you codes. It can however be read at the dealer or a properly equipped garage.

The TPS is also my suggestion. It could be something as simple as it came unplugged on the transmission side of the sensor.

There are two plugs from the TPS, a 3 wire and a 4 wire. I believe the 4 wire is the one going to the transmission/TCU. Unplug it, spray some WD-40 in there and plug it back together and see if it works.

I had a very similar problem, ended up being the fluid. THe fluid was mixed between mercon and atf+ fluid. Apparently the aw4 doesnt like atf+ fluid so it acts funnily with atf+. Either way i would change the fluid/filter.

pete

I'd check the TPS. There should be a thread somewhere showing how to test it on here. Mine did something similar, and it was the TPS.