Over the last couple of weeks I noticed my TC was acting weird.  When its engaged over 45mph and I hit the brakes the TC disengages like its supposed to but then immediately reengages as soon as I let off the brake and its a noticeable reengagement.  It has never done that before.  It would always stay off unless I got back on the gas pedal.  I scanned for codes and it had 2 codes.  One for APPS low voltage and one for charging system low.  So I bought a new Timbo APPS and installed it today.  The TC is still acting the same.  I checked the alternator and it is charging normally.  I did notice that the AC voltage is up though.  When I first did the WT mod the AC noise was at almost nothing but now its at .05 VAC.  I may have to replace the alternator again.  This ones only about 2 years old.  Anything else you can think of that would cause the TC to act like this?

 

I also have another question.  If I go with a Nations alternator (I want a better quality alternator) will I have to get a different breaker.  I currently have a 150 Amp breaker installed but the Nations Alternator is 180 Amp.  I'm guessing the 150 amp breaker will be good as the truck shouldn't draw over the 136 Amps that the OEM alternator is rated for unless something is wrong or I add something that would draw more power.

 

 

11 hours ago, wil440 said:

What's lockup like when you drop it in and out of 4th, is it still harsh or not 

 

 

If I coast and the transmission unlocks on its own its nice and smooth.  When accelerating and it locks on its own its OK too.  Its only when I'm over 45mph and hit the brake and let off it unlocks and locks back up again harshly.  If I hit the brake and hold it down till less then 42ish mph it unlocks harshly but never tries to re-lock.  Like I said... weird 

 

When my wife goes to work tomorrow and the garage is free, I will pull it in and re-do the connectors for the W-T mod and then pull the PCM plugs and clean them and give them some dielectric grease.  

 

Oh and kick the tire...

Are you using ATF+4 transmission fluid?

 

I know that if you run the older ATF in the transmission it will lock harsh and some times shudder a bit as it locks up. 

Yes, ATF+4

 

what happens if you brake but don't let off, this shouldn't then come out of lockup at all it should just drive against the brake

 

it just seems odd that everything is as it should until you step on the brake

When the brake peddle is depressed pin #C1/9 of the antilock brake controller, pin #24 of the ECM, and pin #C3/24 of the PCM all ground through the brake light switch to grounds G200 at the left cowl, G201 at instrument panel right center support, and G100 left fender.   This grounding signal or lack of may have an effect on the lock unlock problem.

3 hours ago, IBMobile said:

When the brake peddle is depressed pin #C1/9 of the antilock brake controller, pin #24 of the ECM, and pin #C3/24 of the PCM all ground through the brake light switch to grounds G200 at the left cowl, G201 at instrument panel right center support, and G100 left fender.   This grounding signal or lack of may have an effect on the lock unlock problem.

Thanks, I will add these items to my list of things to check tomorrow.

Did you check G100 earlier in the thread when I mentioned it as changed my lockup engagement ?  Also the really bad wire that was causing my wiper turn signal problem was buried inside the bunch and not visible just by looking, only found the 1 strand wire by cutting the terminal off and prising it apart and it is only crimped by the way

 

There is 2 grounds to the front and below the  drivers battery

 

Well, I redid the connectors for the W-T mod and I pulled the battery tray on the drivers side.  I only saw one ground in that area, it was a single stud with a bunch of wires in one ring connector.  It didn't look bad.  Did you all bolt that vacuum solenoid thing back up to the battery tray?  That thing was a pain in the @ss to get to.  I pulled all the connectors from the PCM and blew them all out and put some dielectric grease on them and reinstalled.  I will give it a few days and see if it comes back.  Fingers crossed!

mine has 2 grounds there both factory not added

10 hours ago, wil440 said:

mine has 2 grounds there both factory not added

odd, maybe I missed it.

not quite in the same place as the G100 with the bunch of wires it's more on the round of the wheel liner

 

Yes the cruise can is a pain to get the strip with the 2 studs back in the right place AND to get the nuts on from underneath without pushing the POS up need arms 7ft long

 

Be careful calling that ground with the bunch of wires to it OK I did the same mine was not ok so pulled the battery and tray twice instead of once

 

I would advise redoing that one which is G100 and the other one which is close by and check the one on the top area of that fender

17 hours ago, hdpwipmonkey said:

Did you all bolt that vacuum solenoid thing back up to the battery tray? 

I'm lost, I don't think I had that. Must be a 99 thing.

54 minutes ago, Dieselfuture said:

I'm lost, I don't think I had that. Must be a 99 thing.

My 98 Gas 3500 has one too, pain to get to

That has to be the solenoid for the cruise control. 02 and some 01 manual trucks do not have them. Cruise is all fly by wire.

2000 up should all be fly by wire cruise control. The vacuum motor for cruise was used for Automatic transmission mostly for the throttle valve cable. Manuals switched over to fly by wire being there is nothing mechanical needed to be move or pulled.

If you just take in account of all the little things that changed from 98.5 to 02 for our truck you would be surprised. 

• Crank sensor relocated to cam sensor the actual cam sensor function was removed. 
• Vacuum cruise to fly by wire for manuals. 
• Full disc brakes from drum rear brakes.
• RWAL upgraded to full 4 wheel ABS
• 3 MAP sensor changes.
• 53 block. Which they upgrade to fix this.
• Killer dowel pin gear case change to prevent this. 

This is just a small sample of the changes in 4.5 years. 

Been 5 days and my issue hasn't come back 

 

 

I think its been long enough to call it fixed.  Thanks everyone for your help and input with this issue.

 

 

2 hours ago, hdpwipmonkey said:

I think its been long enough to call it fixed. 

Now if those electrical gremlins don't stick their heads up for a while it will be great.

So what steps did you do and which one do you think fixed it? 

On 3/15/2021 at 7:50 PM, IBMobile said:

 

 

Now if those electrical gremlins don't stick their heads up for a while it will be great.

So what steps did you do and which one do you think fixed it? 

Replaced both batteries, cleaned up the terminals, cleaned up the one ground in front of the drivers side battery, and pulled the plugs from the PCM and cleaned and put dielectric grease on them and reinstalled.

The gremlins didn't stay away long.  I am now getting random drop outs of the tach and the CEL comes on and it has 0336 codes.  I just changed out the CKP sensor awhile back after it developed these same symptoms but now they are back.  Either the sensor I installed is a POS (I did get it from Autozone) or there is something else going on.

I forgot is cps on a 5volt reference circuit ? That shares other sensors like oil sending unit. I remember @Me78569 had an issue with something, oil sensor was internally shortened out and messing with the 5 volt reference. 

Or it could be your tone ring on the crankshaft, there were others that had this issue with the tone ring coming loose. I think you could see the tone ring through the sensor hole, maybe try rotating the engine while you looking inside, at the same time using a screwdriver see if that ring is loose. I'm not saying stick a screwdriver in there and turn the engine, I'm sure you know that.