[crash]

I wasn't going to post any of this, but with all the :raimnbow: :flipoff2: newbies, figured some questions could be answered, plus answer some of the real questions..

Some background on the truck.

94 X-cab, IFS :rainbow: had a 3.0 3vze and an auto.

The guy put a 90 4.3 TBI, a manual trans(I wanna say W56 but not 100% sure there), he used AA apapter for the trans along with the nec flywheel/clutch and slave. He used the NWOR motor mounts, headers and radiator. Not sure whos mounting hardware he used for the accories on the front of the motor, but all V-belt with billet alum. brackets.

He had got as far as the bolt on stuff and thats where he got scared and called me, drug it to my shop and this is what I saw when I opened the hood.

On inspection, I found the howell harness plugged into all the sensors on the motor, first step, I ripped that POS off the motor.

The routing totaly sucked, was not in the least bit impressed, called him and said I WILL NOT be using the harness and got the stock harness..

Here is what I hope to accomplish, wire it so all the fusable/relayed circuits still operate in the same fasion as the 3.0 did..

First step, trim the 3.0 harness

This is what I was left with to use the exhisting circuits(at the 3.0 harness to dash harness)

Sorry Crash - your spelling KILLS me DRM

 

[82FB]

Cool, I love following along on threads with pictures.

My 4.3 swap looks only marginally better wiring wise. Maybe someday I will go through the stock harness and pull out all the unnecessary wires... but probably not. Takes a lot of time.

 

[crash]

After I accomplished that, was time to tear the rh side of the dash apart to figure where in the hell I was going to put the ecm. Now the gm ecm is much larger than the toy, and even if I could make it fit with some cutting, no way I am going to put it that damn low...

After about 2 hours of beatin my head, here is what I figured out... First off, the lh portion of the glove box is GOING to have to be cut, no way around it...

First thing I had to do, relocate the ABS module. First I cut all the mounting tabs off the module, and there is just enough room on top of the heater box(portion that has the heater core). The yellow arrow is where it sits now, red is where it was.

Here is where the ecm will be going

As you can see, there is just no room for it, and its up against the underside of the dash/vent assy.. The red arrow is the only concern of it being in that spot, the recirc door cable, but I should be able to work around that.

 

[xextr3m3]

nice

 

[crash]

Now came the next part, hack this up

Thats a full GM harness, removed what items I needed(pics to follow in the next couple days)

Another thing, will be using the stock guages, here is how I mounted them on the 4.3(sorry for the poor pics)
here is the temp sensor (3/8 npt to 1/8 npt adapt) on the pass head

For the oil pressure sender, tossed the OEM one, used 1/8 npt male/male to 1/8 npt elbo, bamo!

By tommorow evening I hope to have the enging portion of the harness all finished...

 

[Brad]

Hey Crash, what are you gonna do witht he Howell harness? Ill take it if its not gonna get used, I got a buggy with a body so it would work for me

 

[Yotaonly]

What did he do to that Howell harness? Mine came with all the loom on it and routes very nicely. Did he think he had a better way to do it? Looks like a nasty mess.

Nice work Crash. Always like reading about your work.

 

[DRM]

Crash, for the last time....


ProJect, not ProDJect :shaking:

 

[rockota]

After I accomplished that, was time to tear the rh side of the dash apart to figure where in the hell I was going to put the ecm. Now the gm ecm is much larger than the toy, and even if I could make it fit with some cutting, no way I am going to put it that damn low...

One of these days I need to take a picture of where mine ECU is mounted.... it's on the bottom *underneath* the glove box in teh factory Chevy plastic housing. Had to trim the kick panel a bit, but you really can't even tell that it's there (black plastic housing) and it's out of harms way.

Crash,

since you are cutting up a harness anyway, why did you elect to not use the Howell harness?

 

[ROKTOY]

Nice work.....looking forward to following this thread Crash!

In my truck, I actually mounted mine on the passenger floor board up under
the glove box....where the floor is sloped. I added some foam padding to fill in
the rest of the area around it to make the whole area even. The passenger lost
a wee bit of leg room, but never knew it. Sat there nestled under the carpet.......

Jay

 

[tuckn18s]

Hell yeah Crash! Your thread couldn't have come at a better time. My 4.3 is a little newer (96) but same stuff essentially. I also decided AGAINST using the Howell Harness for a number of Reasons. First being the cost of the damn thing. I did a little bit of looking around before I found my 4.3 and managed to find one with the harness and computer intact. Sent the Harness out to Jims Performance in Maryland and thing should be good as new. To all of you reading this, unless you cannot locate a harness for your motor, don't go blowing your cash because it is "convenient". Do a little searching around and keep the bucks in your pocket, maybe blow it on something later. Crash, thanks also for the pics of the temp and oil senders. You already referred them to me earlier as to their location but a picture never hurts. Thanks again for the thread!

 

[crash]

Hey Crash, what are you gonna do witht he Howell harness? Ill take it if its not gonna get used, I got a buggy with a body so it would work for me

I don't know what the kid is going to do with the harness, what do they go for new?

 

[crash]

Crash, for the last time....


ProJect, not ProDJect :shaking:

It's da ******* way :flipoff2: :flipoff2:

 

[crash]

One of these days I need to take a picture of where mine ECU is mounted.... it's on the bottom *underneath* the glove box in teh factory Chevy plastic housing. Had to trim the kick panel a bit, but you really can't even tell that it's there (black plastic housing) and it's out of harms way.

Crash,

since you are cutting up a harness anyway, why did you elect to not use the Howell harness?

I prefer to keep all unsealed, hates water control modules as high as possable, even if its a "chromey/pretty boy" rig, and being on the bottom can easier build up radiant heat, another killer of those ecms..
Why hack up an expensive harness when I can do the same, make it fit/taylored to the rig perfectly for cheaper? I am not doing/don't do these rigs for free and didn't wanna see the kid pay alot more than needed..

 

[Rwhat]

Good thread..

good thread Crash, i liked the last one you did. Keep the Tech coming.

 

[crash]

Nice work.....looking forward to following this thread Crash!


Jay

Thanks jay, granted, this won't be a cakewalk, I have to make sure all the subsystems also work,so this will be a little bit of a learning curve for me(if I had my way, would have gutted the whole rig,lol)

ok, almost got the engine side of the harness roughed in

 

[crash]

Ok, I spent a good part of the day going thru ALL DATA at work, pulling up as much info/wiring diagrams as I could, but one thing I am having a hard time figuring out. According to all the info I read, the speed sensor for the toyota ecm/subsystems(cruise/traction control/abs) is built into the cluster(I remember them starting that mid/late 80's) and thats all the info I could find, but the rig has a speed sensor in the t-case with no speedo cable, so now I got more digging to do. But I also have to call the guy and find out exactly what he pulled from the dash...

 

[steveh]

Hey Crash, maybe this will help with the VSS signal. When I installed a CC in my 88 v6, I traced the wire from the ECU back to the signal generatore in the Instrument cluster and tapped in there. Here's what I found for a 94 Truck:

VSS Wire: Location 1 Right Connector of ECM
VSS Wire Color: Green/Blue
VSS Pulse: 4000
VSS Tach Wire: Location 11 Diagnostic Connector
Tach Signal Wire Color: Black

 

[crash]

Thanks steve, but I am still unable to locate the info I need. Every bit of info I have does not have or even tell that there is a speed sensor at the t-case, ugh! Time to really start digging!

 

[jasonmt]

Crash:
If memory serves correct, that year of truck the 3.0L/Auto (A340F?)/VF1A would have had a speedometer cable driving the speedometer and VSS sensor in the instrument panel SP1 in to the ECU (GRN/BLU) and a VSS in the ECT solenoid on the transmission, SP2 in to the ECU (BRN/RED). However it appears that the truck now has a manual (W-56) and a RF1A which did come in later model trucks with a VSS right on the t-case and an electrical speedometer. At this point I am unsure if this signal from the t-case with the VSS goes to the ECU direct and the speedometer or if it just drives the speedometer and a VSS in the speedometer as well which sends this signal to the ECU? This will not matter though because you just need a VSS signal? If you confirm the transmission/t-case models you can just get the proper speedometer drive assembly for the t-case and hook it up and you should get the VSS signal from the original instrument cluster.

Hope this helps?

EDIT: What do you require the VSS signal for, as I realized that all of the above may have answered an unasked question?