Before & After - My 1993 K1500

[93 Krawler]

The VSS that is on the tail of the t-case won't work on this setup. I had to drill and tap the t-case adapter for a VSS. This will keep the correct speed even in low gear so I don't have messed up shift points. The t-case has a switch that sends a signal to the PCM so it knows it's in low gear, but the new pcm doesn't have this signal so I can't use it.





My tie rod and steering ram was behind the axle, and I had minimal clearance between the ram and oil pan on the old engine. The 5.3 will be moved forward 1" because of the new t-case adapter is 1" thicker. So the tie rod and ram had to be moved up front for oil pan clearance. Mark, aka Waffle, moved it up front for me. Now I have to watch out for rocks hitting the tie rod. The plus side is I can lower my bump stops some since I don't have to worry about my oil pan smashing my ram anymore.

[93 Krawler]

Got the engine done and dropped in.



The PCM is going where the coolant bottle is. I will have to get a smaller one and relocate it. It should fit nicely there.



This is what I'm using for my fuse block.



Trans and transfer case are in. Thanks to the engine mount adapters, everything lined back up in the original locations.




So far the only things that didn't bolt back up are the trans shifter linkage and the exhaust. The new trans has the module on the side so the bracket hits it. The exhaust should be an easy fix.

[monkeystrong]

This is really cool Kevin.

[93 Krawler]

Originally Posted by monkeystrong

This is really cool Kevin.

It's taking a lot longer that I anticipated. I'm missing wheeling trips.

[93 Krawler]

I have my fuse block wired, and only a few left to run in the cab. I can't seen to find anywhere that will tell you how big the supply wire should be going the fuse block. It is running the basic engine stuff, but not the starter or any fans. Just injectors, coils, trans, pcm, MAF, TAC, O2's ect... I have a #2 awg running from my battery to a factory junction block just above the PCM and new fuse block. My plan is to run a wire from the factory fuse block that is key on power to a relay that will power the new fuse block, and grab the power from the always on #2 wire above the PCM. I didn't think it would be good to draw from the factory fuse block to power the new one. What size relay should I use and what size wire should supply the block? I'm more familiar with house wiring than I am with 12v auto wiring.

[93 Krawler]

Here is a chart, but I still don't know what the load will be on the fuse block. The wires running the injectors and most everything else are small, like 16-18 gauge. I have 7 - 15 amp circuits and 1 - 20 amp. That's 125 amps. So according to the chart, I only need a 10 awg supply since it is 18" long. Anybody...

http://www.offroaders.com/tech/12-vo...gauge-amps.htm
Amps @ 12 Volts LENGTH OF WIRE
American Wire Gauge (AWG)
3' 5' 7' 10' 15' 20' 25'
0 to1 18 18 18 18 18 18 18
1.5 18 18 18 18 18 18 18
2 18 18 18 18 18 18 18
3 18 18 18 18 18 18 18
4 18 18 18 18 18 18 18
5 18 18 18 18 18 18 18
6 18 18 18 18 18 18 16
7 18 18 18 18 18 18 16
8 18 18 18 18 18 16 16
10 18 18 18 18 16 16 14
11 18 18 18 18 16 16 14
12 18 18 18 18 16 16 14
15 18 18 18 18 14 14 12
18 18 18 16 16 14 14 12
20 18 18 16 16 14 12 10
22 18 18 16 14 12 12 10
24 18 18 16 14 12 12 10
30 18 16 14 12 10 10 10
36 16 14 14 12 10 10 10
40 16 14 12 12 10 10 8
50 16 14 12 10 10 10 8
100 12 12 10 10 6 6 4
150 10 10 8 8 4 4 2
200 10 8 8 6 4 4 2

[underpowered]

when dealing with electric, bigger is always better. especially when dealing with DC. also, if it is a sustained load you want to go bigger as well. No way i would run 125 amps through 10g wire. chances are you are not sustained amps, so any of your individual breakers should trip before you hit full current pull


I know industrial wiring, 10g is 30 amp wire, for 125 we use 2awg. granted this is 120-480v vs 12v, but an amp is an amp no matter the voltage. If it were mine, i'd use no less than 6awg on a feed such as that.

[93 Krawler]

Originally Posted by underpowered

when dealing with electric, bigger is always better. especially when dealing with DC. also, if it is a sustained load you want to go bigger as well. No way i would run 125 amps through 10g wire. chances are you are not sustained amps, so any of your individual breakers should trip before you hit full current pull


I know industrial wiring, 10g is 30 amp wire, for 125 we use 2awg. granted this is 120-480v vs 12v, but an amp is an amp no matter the voltage. If it were mine, i'd use no less than 6awg on a feed such as that.

I know what you mean, I have 2/0 for my battery cables.

My factory battery cable was like #2-4, and there was a #6 that ran everything but the starter. I think the charge wire is a #8. If you add all the power wires that come out of the loom on the 5.3, I'd say they are about the size of a #8 max. I don't even see how a 18g wire can handle 10-15 amps. DC is confusing as far as loads.

In a house panel, the breakers add up to more than the the service size. Does the same apply to DC. If you add all the fuses in any car, I bet it adds up to more that the battery cable size. I guess wattage plays in there somewhere. Like high power car amps. they take huge wires.

I'm with you, go big. I'm getting a 150 amp relay, and run a #4 to it. If that's not enough, then I give up.

[93 Krawler]

Originally Posted by Waffle

My winch came with 4 ga for 320 amps.

160 amps, 1920 watts, needs a #8. Ugh, my head hurts... That's a lot of watts... I don't think I'm anywhere close to that.

[underpowered]

Originally Posted by 93 Krawler

I know what you mean, I have 2/0 for my battery cables.

My factory battery cable was like #2-4, and there was a #6 that ran everything but the starter. I think the charge wire is a #8. If you add all the power wires that come out of the loom on the 5.3, I'd say they are about the size of a #8 max. I don't even see how a 18g wire can handle 10-15 amps. DC is confusing as far as loads.

In a house panel, the breakers add up to more than the the service size. Does the same apply to DC. If you add all the fuses in any car, I bet it adds up to more that the battery cable size. I guess wattage plays in there somewhere. Like high power car amps. they take huge wires.

I'm with you, go big. I'm getting a 150 amp relay, and run a #4 to it. If that's not enough, then I give up.

i dont think the same thing applies to your vehicle as your house. In your house, you won't ever be running everything in your house at the same time. have every light on, something in every outlet running ac, heat, dryer, stove, washer, fans, etc.... but in vehicle, you certainly can be. it is possible to be driving at night running your lights, wipers, heater/ac, stereo, powering your engine, fans, fuel pump all while winching yourself out. So there is a chance you could see near full load on all systems at once in a vehicle compared to your house.

wattage=amps x voltage, so it does play a roll in it all, just a different way of stating amps. people seem to like seeing watts better than amps. they prefer a 55 watt light over a 4.6 amp one even though they are the same thing stated differently.

[93 Krawler]

The guy that built the one in this pic does all kinds of harness building. The main wire feeding the 30 amp relay looks to be a #10. He only has 4 fuses, a fuel pump relay, and the switched main power relay. I see this all over the net. I don't see anyone running big wires to run the engine harness. Maybe they are wrong, or maybe I'm over thinking this...

[93 Krawler]

Getting my stock gauges to work was a pain. The stock 93 temp sender is 1/4" NPT, and the 04 is a 12 x 1.5 thread. They make an adapter, but everyone complained that it suck out so far that the reading was off. I saw one guy took the stock one and milled it down and threaded it to fit the 5.3 heads. So I did it that way. Worked great. I can use an adapter for the oil pressure sender.


Removing the over flow bottle left a perfect spot for the ECM. The fuse block fit perfect over the spot where the old pcm wires went through the firewall. Now I need to find a smaller coolant bottle to mount.




Made some good progress thanks to Waffle coming over to help. Got the exhaust done, steering lines back on and filled, radiator in and filled, trans lines ran, and then the best part, starting it up. Runs great. It's throwing an engine code. The MAF circuit is low or something like that. Hooked up the scanner and it says the IAT temp is around 230 degrees. That is way off. The engine didn't have the MAF sensor, so I got one from u-pull. It looks like it needs to go back. Still have to make a better air intake duct. The stock one is too bulky. There is a lot of little stuff to do now. It will be back on the trail real soon.

[93 Krawler]

The MAF wasn't bad, the pcm ground that goes to the sensor was grounded to the chassis. Oops... It was an easy fix. Runs great now. I should have it done by the end of this weekend. Might take it to Haspin for a test run.

[93 Krawler]

Ok, here's a good one. I added a vss to the tail of the trans so the pcm wouldn't mess up the shifts when in 4 Low. There is no vss in any other spot. When I put it in 4 low, the spedo is off and it shifts super quick. How is this possible? The trans tail should not be affected by the tcase. I don't get it. Anyone?

[underpowered]

speed is off as your VSS is now before the T-case. so you will be going slow, but your VSS is still reading as if your setup is 1:1, not 2.72:1 that it is.

Even on my 4wd vehicles, the Vss has always been on the t-case and usually a switched contact in the PCM to recognize it is in low range to adjust shift points while still keeping the speedo correct since it is on the final output, not before the lower gearing the t-case provides

[93 Krawler]

Originally Posted by underpowered

speed is off as your VSS is now before the T-case. so you will be going slow, but your VSS is still reading as if your setup is 1:1, not 2.72:1 that it is.

Even on my 4wd vehicles, the Vss has always been on the t-case and usually a switched contact in the PCM to recognize it is in low range to adjust shift points while still keeping the speedo correct since it is on the final output, not before the lower gearing the t-case provides

The speedo and shifting is spot on in 2wd and 4 high. It is about 3x off (30=90) in 4 low. It acts as if the vss is still in the t-case. There are no wires on the t-case or t-case shifter at all. The speed of the trans output should not be affected by the t-case being in low, but somehow it is. Advanced adapters sells this kit http://www.advanceadapters.com/produ...-output-shaft/. I ordered the clamp on reluctor ring from them. I already had the VSS. This makes no sense at all. There is no way that the pcm knows the t-case is in low gear. It must be psychic...

[blazerbrad]

Sounds like the issue is because it does not know the t-case is in 4 low.

With the speed sensor on the trans lets say that when in high range, third gear (1:1) in the trans, and 2,000 engine rpm the speed sensor sends out a signal that equates to 45 mph. You now shift into low range, third gear in the trans, and 2,000 engine rpm and the speed sensor sends out the exact same signal and makes the ECM think you are still going 45 mph. However since the t-case is in low range the vehicle is actually only going about 16 mph (2.72 times slower...or about 3 times).

Do you still have the VSS on the tailhousing of the t-case that you could hook up?

[underpowered]

Originally Posted by blazerbrad

Sounds like the issue is because it does not know the t-case is in 4 low.

With the speed sensor on the trans lets say that when in high range, third gear (1:1) in the trans, and 2,000 engine rpm the speed sensor sends out a signal that equates to 45 mph. You now shift into low range, third gear in the trans, and 2,000 engine rpm and the speed sensor sends out the exact same signal and makes the ECM think you are still going 45 mph. However since the t-case is in low range the vehicle is actually only going about 16 mph (2.72 times slower...or about 3 times).

Do you still have the VSS on the tailhousing of the t-case that you could hook up?

this is what i was saying, he just said it better.

your Vss is before the gear reduction of the t-case so therefore the speedo is not accounting for the 2.72:1 gearing of the T-case when in low range. IMO use the VSS for the T-case and you should be just fine.

[93 Krawler]

This all makes sense. The only reason I put it in the trans was from what I read. Multiple articles said You had to put it in the trans tail. I will hook the one back up in the t-case and see how it works.

[93 Krawler]

Does anyone have a clue as to why my IAT is reading is so low? It's not the MAF, I've switched it with one from a different vehicle. Mine also reads correct on that vehicle. The temps shown are basically room temp, key on, not running. I checked the MAF temp and it was 74 degrees. At least the coolant temp is right.
Would a larger gauge wire mess with values? The black signal wire from the MAF to the pcm needed to be lengthened, so I used a thicker wire to do it. I started looking for a problem because it was throwing a code for bank 1 & 2 being rich. It only seemed to throw the code when I was stomping the gas from a dead stop. I think the rich problem is coming from the fact that I am running a t-stat that runs at 182 fully open and the IAT reading cooler than the air really is. It feels a little sluggish when it takes off WOT in 2wd.

[blazerbrad]

Sounds like you ruled out the IAT sensor itself and generally if the circuit is shorted or open you will get an extreme signal one way or the other (like -30 or 300).

Next step is to verify the reference signal. Should be getting a 5 volt signal to the sensor. The PCM supplies both the 5 V and the ground.
Not sure about the wire size causing the issue. If the IAT is reading too low that should correspond to a higher resistance, and I would expect the larger wire to have a lower resistance. Wouldn't be surprised if you are getting straight battery voltage as I think that this increase in voltage compared to the desired 5V would cause an increase in resistance that corresponds to the temp reading you are getting.

[93 Krawler]

Originally Posted by Waffle

http://ls1tech.com/forums/pcm-diagno...uit-input.html

Read this link for some info and it talks about some details with the iat. Remember that last sensor you had that was grounded to chassis and not to the pcm? Maybe thats the case here or maybe a wire is open somewhere. Anyway, it talks about proper volt and ohm readings for the iat.

The MAF was the sensor that I grounded the signal from the PCM. It was black so I tied it in with the others.

Originally Posted by blazerbrad

Sounds like you ruled out the IAT sensor itself and generally if the circuit is shorted or open you will get an extreme signal one way or the other (like -30 or 300).

Next step is to verify the reference signal. Should be getting a 5 volt signal to the sensor. The PCM supplies both the 5 V and the ground.
Not sure about the wire size causing the issue. If the IAT is reading too low that should correspond to a higher resistance, and I would expect the larger wire to have a lower resistance. Wouldn't be surprised if you are getting straight battery voltage as I think that this increase in voltage compared to the desired 5V would cause an increase in resistance that corresponds to the temp reading you are getting.

I will check the voltage tonight.

[93 Krawler]

There are 5 wires going to the MAF. The pink wire is key on power at 16.42v
The yellow and tan wires on both vehicles with key on, not running, MAF plug disconnected were 5.82 volts. The rest of the tests were done with them running fully warm. I checked the temp of the air filter on mine and it was 105.


-------------------Mine-------------Wifes
IAT temp---------73---------------93
Yellow------------3.14-------------5.06
Tan---------------3.09-------------1.90
Pink
Black
Black/white

Wifes car

[93 Krawler]

Took the truck out for a test run and it did pretty good. It threw codes all day about the MAF low circuit, but it still ran pretty good. It needs some fine tuning. The hill in the video was difficult because you started dragged your diffs about 3/4 of the way up. Took a bunch of attempts, but I finally made it up.

[blazerbrad]

The concept is pretty basic as you are turning a couple solenoids on and off to just shift between the gears. The purpose of the computer is to control and adjust the shift parameters....basically up and down shift timing and shift firmness based on speed, engine rpm, load, etc...

I believe what Kevin is talking about is if everything is working 100% properly the transmission will still upshift into 2nd gear when you reach maximum RPM even if you have the shifter pulled down into 1. In some situations that is not what you want to happen and I think the big hill climb is one of those. It would shift into 2nd and you could hear the engine bog down. It would also be nice to start from a stop in 2nd gear sometimes.

Back to the ECM receiving a signal that the t-case it is in 4 low, I was curious if this was the case and finally got a chance to confirm there is a signal that adjusts parameters if it is low range, just as said above. If the VSS was at the output of the transfer case on the donor vehicle (which assume it was since he had to modify the transmission from the donor to get a VSS) then it is not changing the speed signal itself, but would be changing the algorithm that controls the transmission shift points (which are based on engine RPM, vehicle speed, load, etc...).