Understanding my bits....L76 and T56

Tenrocca · #1 (**permalink**) 10-12-2007, 06:46 AM

Well Ive been accumulating bits and pieces at an alarming rate at present - so much so that the bits are accumulating much faster then I can put them in (whats new hey!)

I have a few questions. firstly what is this 5 pin connection just below the rear of the intak manifold. There is no matching connection on the harness. (also what is the outlet covered by the red plug\breather?)

What is this plug for. I have the ecu pinouts, but I cant figure out what this one is - the location would suggest it could be the MAF, but the connector and wire colours are all wrong. I even acosted a VZ thunder ute owner in the carpark at Jaycar the other day and asked to look under his bonnet (nicely) - it seems to dissapear behind the left headlight somewhere? If its not the MAF (which Im pretty sure it isnt) then is the MAF connection part of the body harness wiring (it does come in through connector J1) Doesnt make sence as a few of the sensors that are wired into the engine harness go out into the body harness and back in through J1 - why then wouldnt the MAF?

Onto my gearbox. Im going to attempt the Aussie Mike shifter mod - and my first peak into it Im feeling relatively confident - its a brilliant method (you should be congratulated once again for PIONEERING THAT ONE MIKE

) The one thing that has me stuffed is I think I may have 2 reverse lockout solenoids - out at the middle hatch and one at the rear. There is only one connection on the harness, and the matching connection on the solenoids looks the same, just a different colour.

Middle:

rear:

Seems odd.

(or Im just stupid which is more likely)

Plums · #2 (**permalink**) 10-12-2007, 07:10 AM

The outlet with the red plug just goes to your brake booster for vacuum assisted brakes (if you are having them).

The five pin plug may possibly be the DOD feature which is not enabled on Aussie Commodores.

The black plug in the second picture hooks up to the main body loom in a Commodore installation.

Onto the gearbox: one is the reverse lockout solenoid, and the other is the CAGS solenoid.

Aussie Mike · #3 (**permalink**) 10-12-2007, 07:14 AM

I think that connector on the front of the valley plate is for the Diplacement on demand control. Ask Phil N about it when you se him next. There are a bunch of solenoid valves in the valley that control oil flow to the lifters so the ECU can shut down 4 of the 8 cylinders. I don't believe it's used on Aussie engines.

The Solenoid on the rear extension housing is the reverse lock out. The one on the detent box is the CAGS solenoid (Computer Aided Gear Selection). When activated by the ECU the solenoid pops out into a little track in the side of the detent block on the shift rail. This forces the shift to slide across from the 2nd gear to 3rd gear gates as you push the shifter up (it could be 4th to 5th gates, I can't quite remeber since I've only had a couple of this type through my shed) . From reports I've read the system doesn't work very well and most tuners disable it. That solenoid is usually only the US boxes or early T56 boxes. On the Aussie T56 the casting where the solenoid screws in hasn't been machined.

Cheers

Aussie Mike · #4 (**permalink**) 10-12-2007, 07:16 AM

It looks like a brand new box. If there's an aluminium tag with some numbers on it under one of the extension housing bolts I can tell you what car your box came from. I can also tell you the ratios and what it's rated at.

Cheers

Tenrocca · #5 (**permalink**) 10-12-2007, 07:19 AM

Ask and you shall recieve!. Beauty, thanks Bobby. That all makes sence now (sorta!)

So is the Maf connection part of the body loom then? - Ill have to grab my diagram and study some more - I had assumed all the connections to the body harness go out through the larger white plug.

Tenrocca · #6 (**permalink**) 10-12-2007, 07:26 AM

Quote:

Originally Posted by Aussie Mike

It looks like a brand new box. If there's an aluminium tag with some numbers on it under one of the extension housing bolts I can tell you what car your box came from. I can also tell you the ratios and what it's rated at.

Cheers

Yep it is new - I think its a T56-3600? Same as used in the VZ and MAybe the VE? The tag says:

92182096 61163
TUET6300 A 00098

Is the black tube across the top just a breather?

(Sometimes I even amaze myself with how little I know

)

Plums · #7 (**permalink**) 10-12-2007, 07:50 AM

I am not too familiar with the L76 but here is what I do know:

On an LS1 loom, all on the same line there will be MAF, IAT, Aircon, and the body loom plug (the one you have pictured). For VZ LS1 cars, the MAF and IAT are just one plug because the IAT sensor is part of the MAF.

alffie · #8 (**permalink**) 10-12-2007, 08:00 AM

You should take the 3-4 lockout solinoid out and make sure it is turned off by who ever does your ECU. Beleive it or not the engine will run bad if it cant sense it! Did you buy a matching loom for you engine? or a Commodore loom and a crate engine?

alffie · #9 (**permalink**) 10-12-2007, 08:03 AM

Also I have been told to wire the reverse lockout to your brake pedal so you cant pull reverse while moving forward

sideshow · #10 (**permalink**) 10-12-2007, 08:46 AM

that plug at front is for power and stuff to engine

look on yr ecu u will probably be missing a plug

and also wil be missing afew oither plugs on the loom

these plugs are part of the body harness

just goto holden and buy a new harness for over 800 bucks

then u have to pull it apart and fit relays and stuff

or u can buy a made up loom from me for abit cheaper

Tenrocca · #11 (**permalink**) 10-12-2007, 03:47 PM

Quote:

Originally Posted by alffie

Did you buy a matching loom for you engine? or a Commodore loom and a crate engine?

Its the standard engine harness from holden. Ill still need he 2nd ECU connector, pedal connector etc to wire it it all up, as Sideshow said it is usually part of the body harness.

Aussie Mike · #12 (**permalink**) 10-12-2007, 06:06 PM

The ECU controls the reverse lock out for you. It won't let you engage reverse unless you are traveling below about 5KMH.

You can probably just disconnect the CAGS solenoid. It's relaxed state is with the plunger retracted. It needs to be energised to engage.

Cheers

400TT · #13 (**permalink**) 10-12-2007, 06:33 PM

Quote:

Originally Posted by alffie

Also I have been told to wire the reverse lockout to your brake pedal so you cant pull reverse while moving forward

I can see the merit in what you are saying, but wiring the reverse lockup to the brake pedal switch in the long term would be annoying wouldn't it. I can think of a heap of situations where I would want to select reverse in a manual when my foot wasn't on the brake.

And then you have those mad Shelby Fest motorkhanas where they include reversing in the course.

alffie · #14 (**permalink**) 10-13-2007, 12:38 AM

My Corvette engine loom has everything in it. The only bit it doesnt is the trans loom because it is a trans axle. Took me awhile to work out the ABS ECU is on the lh front gaurd on the Corvette so the engine Harness has alot of extra plugs and a complete loom for the ABS that is very nicely wrapped in heat sheild and black mesh that looks a million bucks that I have to pull open or cut the unused loom off for the bits that I dont need. I have to get from the ECU to the pedal etc the harness has all the engine sensers in it.

sideshow · #15 (**permalink**) 10-13-2007, 02:57 AM

hey alffie have u got complete set

like matching enigne and wiring and ecu

i am just researching alot fo stuff for l76 and ls2s

they have afew minute differences between years and also between enignes and between countries

if u have the enigne with matching loom and matcing ecu then yr set

if not u might run into probs

i am starting to learn all the differences like when running l76 with ls1 ecu and wiring and what ecu goes with what and what sensors are compatable
and there are alot fo small differences which if not sorted now will cause major headaches later

like crank has to be removed and modified to suit

alffie · #16 (**permalink**) 10-13-2007, 03:47 AM

The LS2/LS7 run the 58x reluctor ring where as LS1/LS6 run a 24x reluctor ring. I got everything out of the ZO6, LS7, ECU, Harness, 02 sensers every thing. Worked out cheaper anyway. The LS7 is only differnt to the LS2 because of how the oil tank is set up. You can get Y body gear as well. My loom was $325us and ECU $190us. Pedal $42us connector $55us. Half the price of Holden.

sideshow · #17 (**permalink**) 10-13-2007, 04:20 AM

thats ok price

cam snesor changes too

there are black coloured crank and cam sensors

and the later are grey

thats another way to tell

i sell pedal connectors for 50 bucks they suit ls1 ls2 ans l76

but the ve 6lt has a different plug not sure what the corvette has

as my usa diagrams have different amount of wires compared to ls1 fly y wire