Using a '93 3SGTE ECU on a '91 3SGTE Engine and Harness Options

[Dr_Tweak]

Some weeks back I had a customer doing a 3SGTE swap into a '91 Celica that I did a wiring conversion for. After he got it back and installed, I asked him for the part number on his ECU since I've seen many situations where the importers send the wrong ECU for the year of the harness. Sure enough, he had a '91 Harness but a '93 ECU. I advised him to get a '91 ECU, but he was having a hard time locating one.

About the same time, I started gathering parts and doing research for making jumper harnesses for various Toyota applications. I located the supplier for the female ECU plugs for a few different Toyota harnesses. When I got one in that matched the 3SGTE harnesses, I though, why not make a jumper harness that goes from a '91 harness to a '93 ECU, or a '93 harness to a '91 ECU? Then customers who run into this situation don't have to find another ECU or repin the whole harness.

Since I had this customer, Bryant, who had this very situation at hand, and since I happened to be going near where he lived on a recent road trip, I decided to whip up a prototype and give it a try.







There it is plugged into a 3SGE ECU as an example. This first one came out a little rough, the production model will be cleaner.

And here it is plugged into the car:



The jumper harness worked PERFECTLY. It fired up the first try and is running great, no codes and no problems at all

If anyone wants one of these jumper harnesses let me know, I'm currently building them to order.

Other applications for this setup include plug and play jumper harnesses for standalone units that don't already have a plug and play setup, like perhaps 3SGTE/Autronic, and so on.

-Doc

[lagos]

I get someone like you or Lagos saying, "Oh well, I guess Tweak is making a mint off of selling these/doing these swaps/wiring that engine...., you guys shouldn't buy this, or have him do your swap, you should just do the swap yourself or find some crappy used parts and solder them together and it'll be just as good..."

Hang on there for a minute...
I actually HAVE recommended your wiring services to more people then you might realize. You seem to do a good job at it (no complaints that i know of), and it saves the typical swapper a headache.

As far as you (or any shop for that matter) doing a swap for someone... No, I normally don't recommend it. Why? Because I feel that you shouldn't own a swapped car, if you don't know whats under the hood. I've gotten PMs from almost everyone of your 6gc swap customers. As soon as their car is starting to have some kind of issue, Im usually the one the run to for help. Most of these guys missed the learning experience of doing their own swap, and then don't know what to do once a vac line comes loose, or they need to change their spark plugs. Thats why my recommendation to future swappers will always be to ....do your own work, learn about your car, save money on laybor, and mail your harness out.


As far as these adapter harnesses go, I think the idea is really cool. I actually thought about doing something similar in the past for a plug and play swap harness a few years ago. There is a company that specializes in making these for honda guys that I contacted about doing this before. Im guessing thats probably who you are using to do these for you.

The only problem I see with them is that there are not a whole lot of people who would have a 93 ecu with a 91 harness. And for 200bucks, you could track yourself down the correct ecu, or repin your harness, if you happened to get stuck with the wrong one.

[Dr_Tweak]

I get someone like you or Lagos saying, "Oh well, I guess Tweak is making a mint off of selling these/doing these swaps/wiring that engine...., you guys shouldn't buy this, or have him do your swap, you should just do the swap yourself or find some crappy used parts and solder them together and it'll be just as good..."

Hang on there for a minute...
I actually HAVE recommended your wiring services to more people then you might realize. You seem to do a good job at it (no complaints that i know of), and it saves the typical swapper a headache.

As far as you (or any shop for that matter) doing a swap for someone... No, I normally don't recommend it. Why? Because I feel that you shouldn't own a swapped car, if you don't know whats under the hood. I've gotten PMs from almost everyone of your 6gc swap customers. As soon as their car is starting to have some kind of issue, Im usually the one the run to for help. Most of these guys missed the learning experience of doing their own swap, and then don't know what to do once a vac line comes loose, or they need to change their spark plugs. Thats why my recommendation to future swappers will always be to ....do your own work, learn about your car, save money on laybor, and mail your harness out.


As far as these adapter harnesses go, I think the idea is really cool. I actually thought about doing something similar in the past for a plug and play swap harness a few years ago. There is a company that specializes in making these for honda guys that I contacted about doing this before. Im guessing thats probably who you are using to do these for you.

The only problem I see with them is that there are not a whole lot of people who would have a 93 ecu with a 91 harness. And for 200bucks, you could track yourself down the correct ecu, or repin your harness, if you happened to get stuck with the wrong one.

Don't take it the wrong way Lagos, we're cool. I don't know what you do for work, but just imagine for a minute that you work a commission-only job, you have just about sealed a good "sale", and then the buyer calls you up and says that someone talked them out of it. (Brian Forster comes to mind). That's happened a few times and that's the only reason I brought it up. I don't know why, but some of you guys think that I'm rolling in dough and I'm not, I'm a regular guy just like you with a family at home who's counting on me to put some food on the table.

Honestly, you have a good point about people learning about their cars by doing their own swaps, and I totally agree it's a good idea. In fact, now that wiring is now my main focus, it doesn't matter to me either way because I LOOSE MONEY every time I do a swap for someone. They are just so involved and you can't possibly charge what they actually cost. (This is why so few shops out there will touch a Toyota swap).

And I have seen your recommendations on the wiring and I do appreciate that.

Actually, you would be surprised. I would say that fully 50% of my wiring customers have the wrong ECU (one way or the other). I know what you would have told them (get a clip!) But yes, there are plenty of people out there that will just cut/solder/repin their harness, and that's FINE! But if they want to save the headache, they can just pick up a patch harness and call it a day. For some people, $199 is a lot of money, and for some people, it's not.

-Doc