EFI Wiring Question

Lynmac · #1 (**permalink**) 02-27-2004, 04:56 AM

Hi,

I am new to this forum, so I hope you all don't mind if I jump in and ask some questions?
My hubby and I are up to the stage of connecting up the EFI system, but have little luck in finding whether we will need bypass bits and pieces connected to the ECU. Its a 1996 XR8 ECU and harness ex police vehicle - apparently it comes with the smart lock etc and other management systems that we are not going to need in a Cobra.
Various companies I have talked to all say they are not interested or its too hard....fustrating.

It is hard to do the wiring yourself or can you just buy a shelf item and connect it up using their instructions?
We have heard that a Holden Camera wiring loom would do the job because it didn't come with all the smart locks, central locking etc.
Our car has all the other wiring completed and was working like a treat until....

Sadly (I think my hubby is still crying) our 351 W carbi motor blew up as it was finishing the steering, brake etc test - our car was so close to getting its VIN.
To cut a long story short we have decided to go for a 5.0L EFI instead as the original 351W can now only be used as a boat anchor.

Any suggestions or advice would be great thanks

Regards
Lyn

Bruce Edwards · #2 (**permalink**) 02-27-2004, 05:18 AM

Lyn,

You are going to have trouble. The 96 Mustang came with PASS system that will not let you start the car with out the correct key. It shuts down the ignition and fuel system. You could use an earlier computer with out the PASS system.
We ran into the same problem with our car using the Mustang computer that comes with the supercharger system we got from Ford for our 4.6 set up.
We ended up having a chip burned for the computer to bypass the lock out. They only got half of it correct and we had to run a wire to turn on the fuel pump.
It can be done but you may wish to get an earlier computer to bypass all the trouble.

tonyvda · #3 (**permalink**) 02-27-2004, 06:47 AM

Lyn,

Dont give up hope. I had the same problem with a BMW engine and they use a similar complex system.

Go to a breakers yard and ask for key set that will spark up your motor. They will be able to supply you with an ignition barrel and key and the computer, (you may also need a little cigarette packet sized EWS box,) to match.

All you need to do is identify which wires into the computer carry the signal from the Key, if you buy the donor cars wiring loom they will easily be identifiable, connect up the wires from the antennea on the ignition barrel ( it may have a matchbox sized amplifier also) into the EWS or into the computer, insert the key, and away you go....

The computer and key (and EWS box if you have it) are a "suited" set so all you really have to make sure is that all the components came from the same car. They dont have to come from the same car your engine did.

I didnt have the computer and key and EWS box from my engine donor car but I simply bought a replacement set of these electronics from a different car and it all works lovely...

Cheers,

Tony

ledge · #4 (**permalink**) 02-27-2004, 04:23 PM

I am putting a ls1 out of a vx commodore in my car and also have similar problems with th built in security on modern cars . At the moment i now of two ways you can fix it . One is to trow away you wiring ang computer and get an aftermarket kit fitted such as a Motec or Wolf 3d and the other is to contact the link bellow and they should be able to make you a new loom and reprogram your ecu to ignore the security part as they can do it for my ls1 at a cost of about 1g . Hope this helps.

http://www.castleauto.com.au/

Bryan Wilson · #5 (**permalink**) 02-28-2004, 05:05 AM

Lyn,
With only four wires going to the engine (ignition, tacho, water temp and oil pressure) I would have got another 351W.
I'll shore be keeping my boat anchor

Cheers,
Bryan

Bruce Edwards · #6 (**permalink**) 02-28-2004, 08:21 AM

Lyn,

It can be done as I said in my first post. It will just take a bit of work and you will need a complete wiring diagram to do it. Have you ask your local Ford dealer if they can give you a copy of the EFI and computer harness lay out for the car you took it from? The best thing to do is get that info and see if you really wish to try it.
Of course you could put it on a boat and send it over I would be happy to sort it out! Think the shipping would be a bit much though!!!

Shelby400 · #7 (**permalink**) 02-28-2004, 02:40 PM

There is a company in Sydney called Quickfit Motor Sport.

www.quickfitmotorsport.com.au

The guys name is Steve and he is a EFI guru. Contact him, I am sure he can help you out.

750hp · #8 (**permalink**) 02-28-2004, 03:27 PM

Lyn, changing from carb to EFI will mean that the cars entire fuel system will need replacing. You'll need to buy a different fuel pump, fuel lines, fabricate a return line, etc. Lots of $$$ to change an almost complete car.

To change from a 351 to a 5.0L motor will require new exhaust headers, as the existing ones won't fit the smaller motor. More $$$$

Wiring changes to wire a 5.0L over and above what you already have in place will also cost more $$$$$$$$

Buying a replacement 351W will most likely be thousands of dollars cheaper than converting back to the EFI 5.0L, and you'll have more power with the bigger engine anyway

Lynmac · #9 (**permalink**) 02-29-2004, 05:52 AM

Thank you all for your tips and ideas.

Ledge we contacted castle auto a couple of weeks ago and they quoted us a similar price - we send the loom etc over and they convert and label everything and send it back. We have a guy coming this week who is a real EFI guru and has done alot of mods and conversions - so hopefully he will do our job, apparently he is a busy man. I like to shop local if I can but I guess sometimes you just can't.

750hp - you may be right about the $$$ for change over - however we weighted up our options of getting another 351W block and getting the car passed through our motor rego authority and it all worked out to be alot less head aches to convert over to EFI. We picked up the XR8 motor for a steal and it has all of the things that you mentioned intack. The only thing that is holding us up now is bypassing the smartlock system in the computer.

It seems like the best solution is as Bruce said throw out the original ECU and harness and go for an after market management system.

Will let you know how we get on this week - hopefully we will be on the road again..............with a permit at least!

Regards
Lyn

Bruce Edwards · #10 (**permalink**) 02-29-2004, 08:33 AM

Lyn,

You do not need to get rid of the harness. In the states the earlier cars did not have the PASS system. Just get an earlier ECM with out the PASS system. Then have some one burn a chip that matches the newer program. The whole thing should only cost you around $300 US. You should be able to pick up a rebuilt computer at a parts store but keep your old one. Call your local speed shop and see if they can burn you a chip that plugs in to the computer to match the other ECM or even make it better. The chip just plugs in the computer on the other side from the harness hook up.
If you get a diagram you will see that not much needs to be moved around on your Cobra to make it work. It is the PASS system that makes it a pain and if you bypass it with an earlier computer you do not have to worry about cutting it out or hooking it up.
The computer needs a direct power hook up to the battery, a switch feed from the switch and you then only need to sort out the gauge feed wires, tach, speedo, and the like that are feeds from the computer.
Trust me you and your husband can do it if you get a diagram.

cameron02 · #11 (**permalink**) 03-01-2004, 03:53 AM

Hi Lyn,

I may be stating the bleeding obvious but have you contacted your local Ford dealer.

I thought/hoped all you had to do was get a new ignition barrel and key and the new key matched itself to the system or something like that.

Hmmm, If not then I'm probably going to be in the same boat.

Regards

Cameron

Lynmac · #12 (**permalink**) 03-11-2004, 05:02 AM

Hello All,

We have made progress with our wiring harness and ecu. Have found a guy here in Adelaide that will wire the car up for us -deals mainly in EFI hot rods and drag cars.
Finding someone that knows what to do was a real run around but have found someone at last!

Doing it our selves would have made for a quick devorce - much easier to let someone else do it.

I have spoken to the ford dealers and when you mention anything about a smartlock or PATS bypass module they all say "Huh what, never heard of one".
As it turns out there is a company in QLD that sell the complete PATS-smartlock bypass module that is wired directly into the harness using the pinouts from the female plug end. Three wires connect into the loom: ground/power/pinout number 4. The web link is
http://www.autoemf.com.au they have a load of information on EFI tech problems as well as pinout diagrams for various parts.

Hopefully next week we can truck our car down to this guy and drive it out under permit the following week!

Thanks for all the previous posts, will keep you in the loop as to what happens next.

Regards
Lyn McArthur