AW4 shifting issues...

Been a LONG time since ive been here. but i grabbed another XJ.

2001, blown AW4

swapped in an AW4 from a 1991

running it off a 1995 TCU

jeep shifts perfectly, except that at WOT the max rpm the jeep will see is 3100-3200

in 1-2 it will go to redline.

the ONLY thing i can think of at all is the output speed sensor rotor is different on the 91 trans compared to what the 95 tcu is expecting (double the number of pickup spots). But im 90% sure we've swapped 91's into newer jeeps w/o changing the tcu.

any help would be great.

91 and 95 should have the same rear output speed sensor, giving 1 pulse per rev. I vaguely remember one of the FSMs showing two lobes on the sensor but I'm pretty sure its still 1 pulse/rev. If it's shifting normally otherwise, I don't think this is your problem.

Check the throttle-tranny cable (often incorrectly call the kickdown cable) and the TPS sensor.

lawsoncl said:

91 and 95 should have the same rear output speed sensor, giving 1 pulse per rev. I vaguely remember one of the FSMs showing two lobes on the sensor but I'm pretty sure its still 1 pulse/rev. If it's shifting normally otherwise, I don't think this is your problem.

Check the throttle-tranny cable (often incorrectly call the kickdown cable) and the TPS sensor.

Click to expand...

TV cable is adjusted and working, i even disconnected it and extended it all the way, bangs into gear when shifting at idle, same 3100 rpm

tps is off slightly from my expectations with the older jeeps, this one is coming it at .90v closed 4.10v open. not adjustable of course.

It's probably two lobes for mass balancing, but only one actually has a magnet in it or something.

... other than that, I got no idea/input... good luck

problem solved. the power mode wire must be supplied 12v, even tho the fsm says not connected. it was basically in comfort mode.

Huh. I thought the power/comfort thing went away with the shift to OBDI electronics. I wouldn't have thought it would make a difference on a 95 tcu.

so did we. apparently all they got rid of was the switch. so if you wanted to wire a valet mode into your jeep you could just run a switch on that wire. 12v is power mode (normal mode) and just leaving it open is comfort mode (aka shifts at 3100)