Differences between engine looms for 1UZ and 3UZ

[Matty Dog]

The 1UZ motor I bought for my project has had the wiring loom cut at the firewall, so when a complete 1UZ engine loom came up for sale on the NZ equivalent of eBay, I bought it.

It arrived yesterday, so I pulled it out of the box and laid it out on the floor.

I noticed that at some stage, a wrecker or importer has scrawled "3UZ" on part of it, so I'm guessing it came off a 3UZ motor, rather than a 1UZ.

Does anyone know if there are differences between the two in terms of wiring?

Just to clarrify, this is just the wiring that goes between the engine/transmission and ECU.

 

[cjsupra90]

Could be significant depending on what 1UZ you have.....

3UZ's were all VVTi and first generation 1UZ's were not. Now if your 1UZ is a VVTi edition, then there shouldn't be much differance if any at all....

 

[Matty Dog]

Damn. My 1UZ has 1989 on the HT leads, so most certainly isn't VVTi.

 

[cjsupra90]

Well I hate to be the one to tell you, but that harness that you got will not work if infact it is a 3uz harness.

 

[Peewee]

Many importers don't know **** about electronics, so that 3UZ could be a red herring.

If its got 8 injector plugs, and 8 ignitor plugs then its a late model loom.
If its only got 8 injector plugs, and 2 ignitor plugs (either near the AFM or near the firewall) then its an early loom.
If the TPS plug is near the side its early, if its at the front, its late.
If it has a CSI plug its early, if not it may be late.

There are many ways to tell the difference.

 

[Matty Dog]

Thanks for the responses.
A pic is attached.

 

[Jake Breyck]

that doesn't look like my early 1uz harness, i dont see the part that goes under the intake for the idle air valve, diag port and cold start injector.
although other parts do look like mine, also i only see 4 injector plugs?

is there more to it that is out of frame?

 

[Matty Dog]

I've asked the seller about it, and he has come back and said yes, it is a 3UZ loom, and apologised. He reckons he can swap it for the 1UZ type, so I guess I'll do that.

 

[cjsupra90]

That is deffinitly a VVTi harness.

Just make sure that he is aware that there is a differance between early and late (pre and post 98) harness's (I.e. VVTi and Non VVTi)... 1uz VVTi and 3uz harness's should be interchangable and thus he assumed that it would work for you.... So make sure that he supplies you with a harness that is pre 98 and you should be golden.....

 

[gloverman]

Did you get it off a Guy called Les or a guy called Paul in auckland? Les was selling one recently which showed 3UZ in the auction and it looked different to what I have seen. I have a full soarer loom and ecu which we were going to wire for sale on behalf of a customer as he is now going for individual throttle bodies and a link. Cheers

 

[sideshow]

that lookslike a loom i recently wired up

if u can post a pic of the ecu plugs ill tell u if tis 1uz

but it also looks like a 96 1uz ls400 or celsior

as most 1uzs after 95 96 have whit ecu plugs
but without a closer pic i cant tell

someitmes there is also a part number on them

so check for it then ring toyota

as peewee said 99% of importers are dumfuks

have u got the ecu

one work of advice which is abit late for u now

never ever buy cheap 1uzs if the loom is cut cause this **** happens

so who ever does this always has this problem if runnign std ecu so only yrslef to blame

but make sur eu get the ecu to math yr engine and loom to match

i have wired up up to 6 diff 1uz looms and ther emight even be 8 or 10 diff ones if u look from 89 to 2000

and ive had early soarer looms that can plug into late model 96 ecus

but none are compatible

emailme pics of the engine and plugs on the gbox

or the ecu u have and i can see what u have

anyway get the ecu witht he loom or u will be in strife again

when stuff liek this happens i usually tell customer to sell the engnien they have and buy a full kit from someone good

this sounds harsh but if u dont have airflow or ignitoers or loom or ecu from same car then u can take decades to get the right parts

heheheheh