L400 2.8L A/T Low Power on Takeoff (kick down cable? TPS?)

[Thomascrom]

I checked the TPS with the van running and got a reading of 0.95V. Believing the perfect value to be around 0.78V, I set the TPS to roughly that value, and checked for flat spots in in voltage with throttle movement. Took the van for a very short test drive, and the shift issue was still present, but no A/T codes.

Today I adjusted the kick down cable a couple more millimeters to further tighten the cable at idle. There was a very small amount of slack in the cable at idle, much less than the original amount. At the current adjustment there is no slack on the cable and throttle movement immediately provides tension, however I am essentially out of threads on the 12MM nuts. The cable is completely tightened on the fine adjustment. I have not moved the lever attached by the 8MM bolts.

The van felt like it ran properly, although maybe a hair down on throttle, I assume due to the readjustment of the TPS. I reinstalled the intercooler and took it for a test drive, shift points felt like they were in the ballpark, power from a standing start was better, there was a slightly noticeable difference between starting in “HOLD” and starting in 1st, but not as pronounced as it used to be when I first purchased the van. Overdrive worked properly and the OD switch worked, with a noticeable down shift when OD was disengaged via the switch at 75-80KPH.

No A/T lights (other than at startup) and no signs of overheating. I did notice one “hiccup” driving at low speed low throttle around town when coming back home. I assume it is form my adjustments not being perfect. The hiccups feel like a wonky downshift from 2nd to 1st or maybe 2nd to 1st to 2nd.

Any thoughts? Should I adjust the lever end of the kickdown cable to get the 12MM adjustment nuts back into the middle of the threaded collar, or let good enough be good enough for now?

Reading your story is very interesting and full of knowledge, but I'm like a Netflix series waiting for the second part! were you able to find the problem? I have had an intermittent A/T light since I bought the vehicle and I have checked the basics and everything has been fine... the vehicle drives without problems but the changes are very short at about 1200 rpm and if you go at 100 110 km/h You go at about 3200 3500 rpm, I don't know if adjusting the TPS can solve it, another thing is that in the code test I have a code 11, which seems to be a TP sensor or the connections but I still haven't found the failure of light A /T that drives me crazy

 

[Thomascrom]

Damn. That's close enough to 0.78V that it's unlikely to be the problem.

Looking at the hydraulic circuit (RWD-V4AW3 section 23B) I'd guess you've lost shift solenoid 1. Could be a break in the wiring (either main wiring loom or inside the transmission), or it might be gunked up. An intermittent break in the wiring would explain the fault code.
The hydraulic circuit diagram seems to show that manually selecting 1st mechanically bypasses/overrides the shift solenoid, which explains why you still get full power when selecting 1st.

I think your next step is to test the solenoid using the diagnostic steps in the transmission fault codes post (assuming you haven't done that already. This thread TL;DR.)

If the solenoid is showing open circuit, you might have to drop the transmission pan and see if the wiring for the shift solenoids is accessible. With some luck you can remove the solenoid without having to pull the entire hydraulic control block: read the service manual first.

Also I want photos.

If you can't fix it in time, then manually selecting 1st whenever starting out should be safe. Inconvenient, but better than burning out the 2nd gear clutch pack from repeated standing starts.

Hello friend, I hope you are well and still active here in the forum, I have been looking for information like crazy these last 2 months about the A/T light and looking for a solution, I have the light always flashing but the Delica does not fail at my end moment It feels firm only that the changes are a little fast, and the gas consumption is a little high at about 17 mpg, adjust the kickdown cable and it feels better, try adjusting the TPS sensor and of the 3 cables 1 only has 5V and the other 2 are at 0.00v I have flashing code 11 which is from what I have read is a connection failure or TP sensor, my question before shooting for a new sensor since they are not as easy to get as I would for test it to see if it is really damaged?

 

[Growlerbearnz]

It sounds like the TPS sensor is malfunctioning. One terminal should be 0v, one should be 5V, and the third terminal should change voltage as the TPS turns.

 

[Thomascrom]

It sounds like the TPS sensor is malfunctioning. One terminal should be 0v, one should be 5V, and the third terminal should change voltage as the TPS turns.

Yes and I don't know how to test it, I wouldn't want to buy one and it's something else, but I think I'll have to buy it to be sure, I have 5V and 0 in the other 2, or take it out and check it to see if there is anything