Transmission or Other?

transmissions

#1

I have a 1998 Toyota 4Runner that is experiencing some minor (major?) difficulty shifting properly. The truck is an automatic and stalls occasionally. Before stalling, the transmission shifts normally through all four gears, after is stalls, it only shifts through first or second for a period of time before it once again begins to shift through all four gears properly. If it stalls again, the whole process begins anew. Thoughts?


#2

Codes?


#3

No codes, I wish! Wondering if it might be the TPS on its way out causing the stalling then transmission problem?


#4

Does it stall at any time? Or while driving? Or after sitting at idle for a while? Or just when you come to a stop (like if the lock-up torque converter is failing to unlock)?


#5

It’ll stall at any time. I was driving yesterday and it stalled going down the road. I throw it in neutral (while still rolling on down the road), it starts right up, toss it back into drive and thats when the transmission acts up and wont shift past 1st or 2nd. After a bit, it shifts to 3rd and 4th and all is well.


#6

I should add that while at a complete stop it has surged, or at least felt like it was (best way I can explain it) through multiple gears. Something akin to shifting from 1st to 2nd but at a complete stop.


#7

You’re transmission is not failing. The TCM is getting confused. I had my truck stall on the highway once. Tried to throw it into neutral and restart while rolling, and it didn’t work. Had to pull over and stop to get the ECM and TCM re-sync’ed.

You need to get the stalling figured out. Typically it will either be an ignition issue or a fuel pressure issue. Most, but not all, ignition problems toss a code. Most fuel pressure problems do not. I’d start there with a fuel pressure check.


#8

Sounds as if it is going into a safe mode do to a sensor failure. A friend’s truck would do this for a failed cam sensor. Have you tried having the codes read?


#9

Thanks Busted, I’ll do a fuel pressure check and go from there. I’ll update as I go along. Thankfully this isn’t my primary vehicle. Knfenimore, I have an OBDII reader but unfortunately the check engine light isn’t on and there are no codes coming up. The one time I’d like for it to be on…


#10

I’ve traced the problem to a faulty shift solenoid valve. The new one should be here tomorrow!


#11

True. I agree that a faulty shift solenoid can cause issues. If that is really your problem than you are good to go. Install new solenoid and let us know how it works out


#12

The new solenoid has been installed and I’m happy to report that all is well! Thanks all for the ideas and advice.