automatic transmission shifting

[waystddaze]

I have a 88 cherokee laredo, 4.0 automatic 3 speed w/overdrive, four wheeldrive. The problem, it has to go up to 4200 rpms. before it will shift into 3rd. (overdrive). I dont know if there is a sensor that could be bad or a vaccuum line. Any help would be appreciated. Ron

 

[MudderChuck]

First I'd adjust the TV cable.
Anyone that hasn't adjusted there Throttle Valve cable do it. WOW. - NAXJA Forums -::- North American XJ Association

Then I'd adjust the TPS and ohm check the ground for the TPS. It grounds at the dipstick holder, one of the smaller wires crimped to a ground ring. While you are checking the TPS, clean the connector with a good electrical spray (I even scub mine with a tiny tooth brush used to clean between your teeth), never use WD-40 on a sensor connector (WD-40, di-electric grease or corrosion can induce resistance on very low voltages, sensor voltages are from near zero to 5 volts usually).

If there isn't any noticeable improvement, things then get serious and we can troubleshot a bit deeper.

 

[waystddaze]

Thanks alot mudder i will give those a try and let you knowif it doesnt solve the problem