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Piker · 04-28-2016, 06:12 AM

Also read this on the same page... and there is nothing anywhere that I can see about cycling the ignition 5 times to reset the TPS...

"After replacing or adjusting the throttle position sensor linkage, the technician should use the diagnostic tool to clear the throttle calibration. Go to the DDR selection menu and locate ACTION REQUESTS. Select RESET THROTTLE CALIBRATION and ENTER to set the 0 percent throttle counts. After the idle counts are established, the throttle should be moved to the Full position to establish the full or Wide Open Throttle (WOT) position (100 percent). The full throttle counts will be the same as the idle counts until the throttle is moved. The full throttle counts are set when maximum travel is reached so stopping before actual full throttle will set the 100 percent point artificially low."

MnTom · 04-28-2016, 07:44 AM

Piker, I don't know if you have this, but pay attention to the part that covers "adapting shifts". It is under the category 'DRIVING TIPS' then 'ADAPTING SHIFTS'.

Piker · 04-28-2016, 10:55 AM

Quote:

Originally Posted by MnTom

Piker, I don't know if you have this, but pay attention to the part that covers "adapting shifts". It is under the category 'DRIVING TIPS' then 'ADAPTING SHIFTS'.

That looks to be for the WTEC III controls? Not sure if it's the same for the WTEC II, which is what our system is.

-cheers

MnTom · 04-28-2016, 07:22 PM

Quote:

Originally Posted by Piker

That looks to be for the WTEC III controls? Not sure if it's the same for the WTEC II, which is what our system is.

-cheers

Dang, shot down again........

HarveyP · 04-29-2016, 09:47 AM

I replaced my throttle position sensor several years ago. I think the actual problem was the "stud" that the throttle cable attached to at the injection pump and held in place with a cotter pin, had worn down and had a groove in it. It had almost cut all the way through the post. I lucked out because one of the mechanics at Allison had a used one in his toolbox that he sold me for $5. With everything you have done to your engine, you may have taken a look at yours, but it was something I had not noticed even after detaching the old and installing the new. Good luck, HarveyP

MnTom · 04-29-2016, 07:17 PM

Piker, check this out: http://www.superflow.com/support/sup...on_WTEC_II.pdf
This may help too: http://ww2.justanswer.com/uploads/HE...e-shooting.pdf

Piker · 04-30-2016, 05:25 PM

Thanks guys... I think I'm good to go...

Since I got the wiring fixed, and since I did the 5 ignition cycle thingy (not sure if that did anything or not)... the shifts have really started to improve with each little road trip we take. It still holds on to the downshifts the same as always when I take my foot off the gas, but now it kicks down a gear with a lot more ease if I decide to get back on the throttle. Actually, I don't think the tranny has EVER kicked down from 6th to 5th above 55 mph, but now if I press the pedal far enough it does. It's actually pretty nice.

I did have the issue of it not wanting to go into gear a couple more times... it really didn't seem like it was idling too high, but I went ahead and turned it down a little anyways. I'll just keep an eye on it, and hopefully that won't be an issue any more.

All for now, and thanks again.

-cheers

MnTom · 04-30-2016, 07:15 PM

Oh I do hope you have it....

Piker · 05-04-2016, 08:17 PM

Hmmm

This thing is shifting better than ever... but I'm still getting that glitch where every once in a while it acts like the idle is too high and won't go into gear... even after I've lowered the idle back down to where it was.

Tonight after a little drive, I shut the engine off while we stopped somewhere... and when I started it back up it it would not engage... all I did though was flog the throttle up to about 1500 rpm and then back down to idle and it went right into gear.

I do notice that the volt meter on the dash won't go up to nominal after you start the engine until the rpm reaches about 1200 or so for the first time. Once you hit 1200, the volt meter moves into the green and stays there regardless of rpm. Not sure what that is all about, but it's always done it... maybe with the new wiring to the tcm this voltage fluctuation is having g an I'll effect?

I'll try to pay attention to what the volt meter is reading next time it won't engage. Any other thoughts?

-cheers

MnTom · 05-05-2016, 08:05 AM

My thoughts are to start the coach and check voltage at the battery while the dash gauge shows low voltage with a DMM, then after the dash gauge shows good voltage. I am wondering if the TCM is not seeing the correct voltage and causing you some issues.

Piker · 05-05-2016, 10:54 AM

That sounds easy enough to do.

I wonder what could be causing the voltage drop in the first place? There's no glow plugs or heater grids on this engine. Is there a relay or something in the alternator that won't allow it to start charging until it reaches a certain threshold? I've never heard of such a thing, but then again... you could fill a warehouse with stuff I don't know.

Maybe it's the relay that ties in the house batteries once the engine is running? Has to see voltage from the alternator before it kicks in? Maybe the jump in voltage is just because 3 batteries are better than 1?

-cheers

MnTom · 05-05-2016, 07:37 PM

I don't know about how yours is, but my 5.9 (in a Dodge) has a crankshaft position sensor that tells the PCM the engine is running so it allow the alternator to charge. The sensor is right above the harmonic damper and the two wires run almost straight up the block to about the level of the valve covers.

Piker · 05-06-2016, 04:00 AM

Well, I guess I need to learn how alternators work and what the wiring looks like... If there's a wire to tell the alternator when to start charging, then I'm guessing it comes from the TCM? There is nothing on the allison wiring schematic that says "alternator" on it, but there are some switched output functions.

It's possible the delay in alternator charging is not what's causing the issue of not being able to shift into gear... like I said, the delay in charging until the rpm is raised has always been there... but perhaps it's just another effect of whatever issue is keeping the tranny from going into gear.

Maybe the engine speed sensor or it's associated wiring is faulty? I'll check the troubleshooting manual to see if there's a way to test it.

Looks like I know what I'll be doing this weekend... more troubleshooting.

-cheers

Piker · 05-06-2016, 04:17 AM

Looking at some wiring schematics for alternators... it appears as if I am simply missing the "field wire" which excites the alternator into charging. I read that the alternator will energize without this wire, but it might take additional rpm's to do it? Maybe this is my issue with the alternator, but I don't know if it will have anything to do with the tranny not going into gear. I'll look into it.

-cheers