V12 ECU

Talk about the E-Type Series 3
User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#1 V12 ECU

Post by Fspp369 » Sat Aug 24, 2019 2:17 pm

Hi everyone ,
I have an S3 with an HE efi engine.
The problem is the ECU came with yards of wire from the donor XJS. This is now folded and wound about the floor of the car.
I want to shorten the loom to place the ECU in a more sensible position rather than in the rear of the seat compartment. Has anyone removed the plug from the loom to the ECU and resoldered it, or achieved a result by any other method?
All/any I nformation gratefully received .
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

hazzardv12
Posts: 14
Joined: Fri Nov 09, 2018 4:55 pm
Location: Langport, Somerset
Great Britain

#2 Re: V12 ECU

Post by hazzardv12 » Mon Aug 26, 2019 6:56 am

I'm about to fit injection to my E. Surely, the easy way will be to select a position for the ecu and then shorten the loom at any convenient position (not at the plug) .Cut one wire at a time,solder joint and shinkwrap
John Hazzard, Series3 2+2 , import but RHD Conversion with modern pas,5 speed conversion and fuel injection, plus DB7 Vantage and turbocharged Jensen Healey !

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#3 Re: V12 ECU

Post by Fspp369 » Mon Aug 26, 2019 7:37 am

Hi,
Yes that is an option but you end up with a rather fat collection of wires.
I would normally do that with heat shrink tubing over each joint but that makes things fatter!
My desire to redo the plug was based on the idea of no extra joints and neatness. I can see that in the end I may have to use the cut and joint technique.
I’m holding fire at the moment, but thanks. As they say ....watch this space!!
Peter
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

jagwit
Posts: 537
Joined: Thu Oct 18, 2012 6:52 am
Location: Pretoria
South Africa

#4 Re: V12 ECU

Post by jagwit » Mon Aug 26, 2019 6:01 pm

Without a doubt, re-terminating the wires right on the connector pins is 1st prize. I have never looked at the connector with that in mind and can not advise on the feasibility of doing so. I would want to have a second connector on hand in case replacement pins are needed.

A safer option is simply to cut the wires, splice, solder and cover with heat shrink. Stagger the joints so that the heat shrink don't all sit in one place making the cable very thick there.

Another option would be to find a large "feed through" / "pass through" bulkhead connector (with enough pins), where you can mount the bulkhead connector into the steering collumn cover plate and terminate the wires (now cut to length) to connectors that plug into the bulkhead connector on either side. Then it won't even look like the wires were "cut" to length.
Best Regards
Philip
Jag: 72 E-type V12, 80 XJS (Megasquirt + 5sp manual O/D)
Jensen: 74 Interceptor (EFI by Megasquirt + O/D 4sp auto)
Chev: 59 Apache std, 70 C10 (350V8, 700R4)

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

jagwit
Posts: 537
Joined: Thu Oct 18, 2012 6:52 am
Location: Pretoria
South Africa

#5 Re: V12 ECU

Post by jagwit » Mon Aug 26, 2019 6:18 pm

Found some nice Amphenol connectors from a catalog here: http://www.amphenol-industrial.com/literature/catalogs
Amphenol connectors.png
Amphenol connectors.png (99.63 KiB) Viewed 5909 times
Best Regards
Philip
Jag: 72 E-type V12, 80 XJS (Megasquirt + 5sp manual O/D)
Jensen: 74 Interceptor (EFI by Megasquirt + O/D 4sp auto)
Chev: 59 Apache std, 70 C10 (350V8, 700R4)

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

jagwit
Posts: 537
Joined: Thu Oct 18, 2012 6:52 am
Location: Pretoria
South Africa

#6 Re: V12 ECU

Post by jagwit » Mon Aug 26, 2019 6:24 pm

When I converted my S3 to EFI, I mounted the ECU (Megasquirt in my case) to the "ceiling" of the passenger footwell. Fit an easily removeable cover over it to prevent passengers from kicking the connector to the ECU.
Best Regards
Philip
Jag: 72 E-type V12, 80 XJS (Megasquirt + 5sp manual O/D)
Jensen: 74 Interceptor (EFI by Megasquirt + O/D 4sp auto)
Chev: 59 Apache std, 70 C10 (350V8, 700R4)

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Barry
Posts: 463
Joined: Thu Jul 05, 2012 1:11 pm
Location: United Kingdom
Great Britain

#7 Re: V12 ECU

Post by Barry » Tue Aug 27, 2019 7:41 am

My Series 3 Roadster has a factory 6.0 litre engine fitted when it was restored in 2005. It has fuel injection with Roger Bywater’s TT Torque Plus kit with larger throttle bodies. The ECU is fitted under the panel on the off-side at the back edge of the boot in front of the bulkhead. That ECU is made by Roger Bywater’s AJ6 Engineering company. A call to Roger will answer any query on that and any wiring loom query.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#8 Re: V12 ECU

Post by Fspp369 » Wed Aug 28, 2019 4:57 pm

Thanks all.
I quite like the idea of using a bulkhead plug but that creates another break in the chain, which whilst making life easier has its downside.
Can we still get new ECU plugs from anywhere? It’s still my gold standard.
Because I’ve changed my seats to modified XjS type I do have a reasonable space under the seats to put the ECU so that’s most likely the site for it. In the passenger footwell gives me the worry that the usable space is then a but small, especially if I’m the passenger with my size 12’s kicking 3 bells out of the thing!?

I’m going to have to get a defunct ECU and loom and try and desolder/re-solder the pins, to practice on.
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#9 Re: V12 ECU

Post by Fspp369 » Wed Aug 28, 2019 5:02 pm

Barry,
I had a brief word with Roger some weeks ago and was left in the quandary that raised the posting.
I also had a chat with Brian Reed about the same...his opinion was leave it and find a home for the cables!
Has anyone got a very good condition plug available?
Peter.
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Barry
Posts: 463
Joined: Thu Jul 05, 2012 1:11 pm
Location: United Kingdom
Great Britain

#10 Re: V12 ECU

Post by Barry » Wed Aug 28, 2019 10:31 pm

It might be worth a chat to E-type UK as they are into installing fuel injection and ECU’s to V12. They have quite a lot of knowledge on the subject and are very helpful. I am sorry if Roger Bywater left you in a quandry. I get the impression AJ6 Engineering is possibly winding down, with many of his bits no longer available. I have to say, if you can get it sorted, you won’t regret it.......

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#11 Re: V12 ECU

Post by Fspp369 » Thu Aug 29, 2019 12:00 pm

Thanks Barry
Never thought of them for this :drinkingcheers:
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links


johnetype
Posts: 389
Joined: Sun Feb 26, 2012 11:54 pm
Location: Worcestershire
Great Britain

#12 Re: V12 ECU

Post by johnetype » Thu Aug 29, 2019 1:19 pm

Fspp369 wrote:
Wed Aug 28, 2019 5:02 pm
I also had a chat with Brian Reed about the same...his opinion was leave it and find a home for the cables!
And that seems like very good advice. If you've got room for the ECU under a seat then the spare cable can live there too. Wiring faults in an ECU loom are notoriously difficult to diagnose and can cause the engine to die in embarrassing places so what is the benefit of introducing more joints/resolders that could fail?

At the time ECU technology was in it's infancy and Jaguar located the ECU in the boot to keep it cool and away from electrical noise despite it costing them a long wiring loom. Something to think about.
John

1969 Series 2 FHC

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#13 Re: V12 ECU

Post by Fspp369 » Thu Aug 29, 2019 4:40 pm

John,
This is precisely why I am thinking of using a new plug and not joining cables unless I really have to,....there is a lot of loom spare when the donor is an XJS believe me!
As for keeping cool, the open environment of an OTS vs the enclosed boot space of said beasty seems to me a more pleasant life?
The electrical noise issue is interesting as effectively the ECU is a faraday cage and as such the spurious signals should not infiltrate the electronics other than along the input wires, the shorter these are the lower potential for induced emf, unless of course one happens to trim them down to the exact wave length of random signals.
As a radio amateur I used to spend a lot of time testing cable runs for resonance and in some cases trying to generate stronger signals, the interesting investigation one might do, I s use a time of flight reflectometer to determine the potential nodal pints along the wiring and avoid them.......mmmmI wandered a bit I'm sorry.

On another point I'm also looking at is making a fuel cooler from the guts of a large portable ice box, the sort that use the Peltier effect to achieve cooling, as I do believe fuel temperature is a significant potential problem in an EFI engined car, it might just be something that keeps me awake at nights during the winter.... :scratchheadyellow:

Peter?
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

MLBS3V12
Posts: 444
Joined: Thu May 19, 2011 6:57 pm
Location: France
France

#14 Re: V12 ECU

Post by MLBS3V12 » Tue Sep 24, 2019 3:59 am

Have you finally decided where you are going to place the ECU and how you will do with the long xjs loom ?
As E Type UK, under the seat sounds to be a good place.
Le chemin sera long!...

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Barry
Posts: 463
Joined: Thu Jul 05, 2012 1:11 pm
Location: United Kingdom
Great Britain

#15 Re: V12 ECU

Post by Barry » Tue Sep 24, 2019 10:03 pm

Safest place is in the boot, under the rear panel. That’s where mine is. Why put it under the seat. Less room, less accessibility, and not really convenient for the loom.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#16 Re: V12 ECU

Post by Fspp369 » Wed Sep 25, 2019 7:39 am

Barry,
Surely the way to the boot for the loom is via the seat area!
It's cooler, remember it's an OTS, and to get to the boot it has to pass through a couple more panels, so that's another bulkhead rubber or similar "gasket", another potential problem area if the loom rubs and gets the edge of the panel. The use of the boot and its stuffing with objects may jiggle the loom and its connector.
Peter.
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Barry
Posts: 463
Joined: Thu Jul 05, 2012 1:11 pm
Location: United Kingdom
Great Britain

#17 Re: V12 ECU

Post by Barry » Wed Sep 25, 2019 1:12 pm

Yes, but don’t stop at the seats, put the blessed thing in the boot! Out of the way, and accessible when you need it. Sorry, another flaw with the E type UK V12’s. They are really trying hard to get their cars right, but they have a way to go yet.....

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Topic author
Fspp369
Posts: 100
Joined: Thu Feb 28, 2019 11:23 am
Location: Coventry
Great Britain

#18 Re: V12 ECU

Post by Fspp369 » Wed Sep 25, 2019 6:16 pm

So do you have any comment about the length of the loom, the passage through panels and the heat situation?
The only thing I'm convinced of, is that it's not going to crowd the passenger footwell.
:scratchheadyellow:
Peter {XKE V12HE efi}

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Barry
Posts: 463
Joined: Thu Jul 05, 2012 1:11 pm
Location: United Kingdom
Great Britain

#19 Re: V12 ECU

Post by Barry » Thu Sep 26, 2019 11:09 pm

My loom was specially made by C & M Wilkinson. Sorry, perhaps I should have explained that.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

MLBS3V12
Posts: 444
Joined: Thu May 19, 2011 6:57 pm
Location: France
France

#20 Re: V12 ECU

Post by MLBS3V12 » Sat Dec 21, 2019 9:04 am

Hi all,
I've finally decided to place the EFI ECU on the passenger side in the car:

Image

I've then shorten the wiring loom to get it fit to the car


Image

Reduction of the wiring loom :hammerdrill:

Image


Because my XJS engine is a "Marelli" one, I've also another ECU to place somewhere.... I do place it on the left side into the car:

Image

I've to shorten the ignition wiring loom now.
Le chemin sera long!...

Link:
BBcode:
HTML:
Hide post links
Show post links

Post Reply Previous topicNext topic