Transmission Shifting issues - A442F Transmission Solenoids Replacements (1 Viewer)

[therestevethedog]

Well, looks like my number is up. Over the weekend I started having transmission trouble. My truck is a 1994 FZJ80 with the A442F transmission. Unfortunately, the O/D light is out so I can't get codes from it. Checked engine codes and there aren't any.

Anyway, when I put it in D I get no power. Transmission doesn't engage and motor limp mode seems enabled. Can't rev over 2k rpm. If I then drop it in to L it engages properly and I can move the shifter to D for normal operation. This started on Saturday and it's not intermittent. That's how it happens every time.

Checked the fluid level - less that 1yo and in excellent shape. Checked the shift linkage and there's no slop there. The wire harness connections to the control units in the driver side footwell are clean with no loose connection or visibile corrosion or damage. Sounds like it really must be a bad solenoid.

Per this excellent thread on the solenoids I decided to source the Isuzu part numbers. I found Transtar Industries at (855) TRANSTAR and they stock them. I was able to order all four solenoids for $85 plus shipping.

I figure at 207k it can't hurt to change them all, so that's my project next weekend.

If anyone has any additional suggestions of where to look, I'd appreciate the guidance.

Thanks!

 

[AgentOrange]

Definitely change them all. Also clean out the filter while you're in there and adjust the throttle valve cable when you're done. I just did this a few weeks ago when I had a similar issue. Felt like I was starting in 3rd gear unless I could coax it into 1st, but 2nd was non existent for the most part.

 

[SmokingRocks]

Pull your cluster and replace the OD bulb, and pull your codes.

I think you can also pull the trans codes from the diagnostic port with a test light IIRC.

Get your factory service manual from the link in my description, and get the A442f manual as well. I put a lot of time into making these manuals easier to use just for situations like this.

 

[therestevethedog]

Man, thank you for the work on those manuals. That's a labor of love and a thing of beauty. Awesome.

 

[therestevethedog]

Definitely change them all. Also clean out the filter while you're in there and adjust the throttle valve cable when you're done. I just did this a few weeks ago when I had a similar issue. Felt like I was starting in 3rd gear unless I could coax it into 1st, but 2nd was non existent for the most part.

Filter is new - just 6k miles on it. Will check fluid condition & magnets but fingers crossed, don't expect much.

 

[SmokingRocks]

I wouldn't run off on a wild goose chase, start by replacing the bulbs in your cluster. I've had my cluster out so many times I can do it in about 10 mins now, granted if you haven't done ti before you'll take longer but it's not hard just follow the steps in the FSM.

SO do that 1st, then pull codes (or check to see if the light illuminates at all because if it doesn't then that means the transmission ECU isn't getting power which I've had happen to me). Moral of the story is to follow the troubleshooting outlined in the FSM.

 

[therestevethedog]

Bulbs ordered. Time to reignite the D light anyway lol

I'll definitely pull those codes before anything else. Hopefully everything gets here before the weekend. Wanted to hit some trails on Sunday but not with the transmission acting like this...

 

[AgentOrange]

Also be aware that failed or clogged solenoids will not throw a code. Mine did not. But definitely follow the test plan.

 

[SmokingRocks]

Bulbs ordered. Time to reignite the D light anyway lol

I'll definitely pull those codes before anything else. Hopefully everything gets here before the weekend. Wanted to hit some trails on Sunday but not with the transmission acting like this...

yea I hear ya and get it. Sometimes you want to put the cart in front of the horse but in this case you'll just end up frustrating yourself. Got to follow the troubleshooting tree that Mr. T laid out.

Also be aware that failed or clogged solenoids will not throw a code. Mine did not. But definitely follow the test plan.

Solid point, replacing the solenoids should be a PM item or at the very least you should have them in your parts bin ready to go whenever.

 

[Zhowardfzj80]

Got mine ordered from a place/part number post on this site. Like $30 total amd they worked great. Came in a box that was labeled "Izuzu"

 

[therestevethedog]

Well, I’m more than 10 minutes in so far, but I’ve just about got the dash cluster out and ready to put in the replacement bulbs.

 

[therestevethedog]

Progress!

 

[therestevethedog]

Well, it took a few hours, and I took the opportunity to clean up some wiring. Ran into a couple things. The transmission is still acting like it was.

On a cold start when I put it D, it is in some sort of a limp mode. Doesn’t really move and limiter is at 2000 RPM. If I switch to L then back to D it shifts as normal.

The O/D light is working properly now and I’m not getting any codes.

Also, I replaced all of the lights and tested them in place on the bench. I don’t remember if they were working before or not, but P and N are not lighting up now that it’s back together. I do have a shiny bright D though!

 

[therestevethedog]

Sounds like clogged/failed solenoids still may not throw codes. Swapping those is next.

Anyone have ideas about where I should look for the P and N light issue? I tested and replaced those bulbs yesterday, so it has to be somewhere else. I found a photo I took a week or so ago and the P light definitely wasn't working then so it's not a new problem.

Thanks!

 

[slow95z]

Maybe the nss?

First instinct is to check the large barrel connector above the starter. Have seen the phh leak and drip coolant into that plug and rot it out on SEVERAL occasions.

I know @voodu3 showed me his solution a few years back and I have since done it on numerous vehicles.

 

[SmokingRocks]

do the solenoids and report back

 

[therestevethedog]

Not great news. No codes. Swapped the solenoids. Still getting the exact same behavior.

It feels 100% normal once it gets into gear but I have to shift to L before D to get it moving. Haven’t tested starting with R or 2.

Any thoughts where to look next?

 

[therestevethedog]

@SmokingRocks any ideas for me where to look next? Feels like it’s electronic. Straight to D and I get the problem. If I put it in L or R first, s***s right into gear properly. Once I’m in D and driving it acts completely normally. ECT mode is solid too.

Thanks

 

[mjosoba]

I was driving an NPR (AW450) with this same issue, and someone said it is a common issue on landscaping trucks when they go in reverse then pop it into drive to try and unload. Can’t remember the actual parts, but it’s some sort of sprague in the transmission that goes out. Could do some googling on that transmission.

 

[SmokingRocks]

I would highly suggest following the FSM's troubleshooting matrix for the automatic transmission starting on page AT-25, do every step, don't skip. That's where I'd start. The manual shifting test on page AT-28 is another invaluable test with a great malfunction troubleshooting table. I've replaced solenoids with units that were bad out of the box once before, so it's worth running the test on them (you can also bench-test solenoids to verify function).

I would also suggest getting an oscilloscope like the pico 2205a or Hantek 2c42 then spend some time watching youtube to learn how to use it. Because you may be tracking down an electrical fault here and having a o-scope (which is basically a multi-meter that tracks voltage over time on a graph for you) can be invaluable in identifying the issue. Also O-scopes are a great piece of kit to have in your toolbox for many other car issues as well so its really worth it, there are hundreds of automotive test you can do that will save time chasing down future issues.

I'll take a closer look at your situation this weekend and get back to you with some more tips on things to check, but you can get started with the FSM's test in the meantime.