98+ Auto to Manual question.

[PlumCrazy]

Doing a 99 3.0 2wd auto to Manual swap.

I have the manual ECU and trans harness, can I swap just the harness and have it drivable so I can get to the dealer and swap in the manual ECU and have it programed to my PATS?

Do I need to jumper anything if I actually have the manual harness?


-PlumCrazy

 

[Earl43P]

Whelp, so far I've looked at (2000) PATS, 3.0 Engine Controls, 4R44E and 5R55E Transmission Controls, GEM and don't see anything problematic, other than you will get a CEL for the missing auto trans "stuff" like OSS, DTR, and whatnot solenoids. As long as the original PATS/PCM remain, the starter should crank over (through the clutch switch)without a PATS interruption, and engine should start/run. You may get idle issues when decelerating with the clutch pushed in.

 

[PlumCrazy]

So i can run the auto PCM with the manual trans harness long enough to drive to a dealer and then swap in the manual PCM and have them match the PATS.

After that it should operate like a factory 5 speed correct?

-PlumCrazy

 

[PlumCrazy]

I figured someone who has done this would chime in.lol Seems as if every time I ask about it I get one "I think it should work" response, then nothing.lol

-PlumCrazy

 

[armadillon]

I'm just waiting for you to do it so I can know the answer

 

[Earl43P]

You could drive it for a good while like that, as far as I can tell.

I'd be really curious about the idle behavior. A 5 speed PCM will prop up the idle to 1200rpm or so until you just about stop, then it'll drop to 7-800rpm as if someone threw a switch at about 5 mph. I can confirm that the VSS signal is used for that "feature".

I expect you to either see a higher idle (very bothersome) or stalling when coming to a stop. I'd be interested to know if either one happens. Other than that, it should start/run/drive.

 

[Snoranger]

I figured someone who has done this would chime in.lol Seems as if every time I ask about it I get one "I think it should work" response, then nothing.lol

-PlumCrazy

Yes, it will start and drive.
But It may not know what gear your in. On my '01 there is a rev limiter (around 3k RPM) in park or neutral, I dont know about the '99. Just keep that in mind.


Is that better then "I think it will work"?

 

[PlumCrazy]

Well just for shits and giggles I plugged in my manual PCM, with all the automatic wiring still intact and in park. It starts up and idles fine. The "Theft" light does blink, but I counted on that. I was under the impression that it should not start with the manual PCM until it was reprogrammed to match the PATS?

Another question came to mind though....does the speedo run off the rear ABS speed sensor, or is it integrated into the auto trans? There is no external VSS besides the rear diff.

Also noticed that the auto trans harness does not have a plug between it and the engine harness like the manual harness, so I guess I will have to loop the neutral wires and splice in my reverse indicator switch. will the manual PCM still flash the "OD off" light with the soleniod plug dissconnected? or do those wires just dead end with the manual PCM?


Edit: From what I have read, there is no VSS in the trans unless its a 4.0 The rear ABS sensor seems to be the only speed sensor on the 98+ 3.0 2wd. The reverse wires are common colors with the manual reverse switch pigtail (purple/or and black/pk, and i just need to loop the pink to the tan/rd and the black to the red/w all on the DTR switch plug.

But I am still uncertain what to do with the other plug that connected to solenoids. If it is left unplugged with the auto PCM I know is blinks the OD off light, but I am not sure if the manual PCM even looks for those wires at all or if they they need to be looped somewhere.

I also noticed that on pre 98 RBVs there is a simple jumper for the clutch safety on the auto models, but 98+ dont have any provisions for the clutch safety. I am not concerned about that though, I have owned nothing but manuals until this thing so its habit to push the clutch.lol

 

[PlumCrazy]

Welp. Did the swap today. I threw in the manual ECU, looped the pink to tan/red and the black to red/ white on the gear selector position sensor, and the reverse light switch wires to their respective colors.

Left the other wires and plug ziptied up for themoment. It starts, runs and drives just fine. The theft light blinks for the 5 mins or so after startup, but other than that it is completely fine.

Speedo works so it must run off the rear abs sensor. Every thing else was bolt up and go. I even pulled the column and stripped all the shifter mechanisms out versus just pulling off the arm.

-PlumCrazy

 

[PlumCrazy]

Im going to see what the dealer can do about the light on Monday.

-PlumCrazy

 

[adsm08]

Well just for shits and giggles I plugged in my manual PCM, with all the automatic wiring still intact and in park. It starts up and idles fine. The "Theft" light does blink, but I counted on that. I was under the impression that it should not start with the manual PCM until it was reprogrammed to match the PATS?

PATS was an option, not standard equipment that year. It is 100% possible that the manual PCM you have is non-PATS and as such will start just fine without having the keys programmed.

 

[PlumCrazy]

Will it run correctly? It seems to be idling a little odd. Can the dealer still kill the light?

-PlumCrazy

 

[adsm08]

PATS is a starter interrupt ONLY. On your year it should only disable the starter, period.

If you want to kill the anti-theft light, just take the bulb out.

 

[PlumCrazy]

Makes sense. It throws a CEL at startup now. Bank 1 & 2 rich. The ECU was a non flex 2000 2wd 3.0 5 speed. My truck was the same but 99 auto. It wont throw the code if the truck is already up to temp, only if it sits and cools off and is restarted.

-PlumCrazy