Engine wires connector + SOME MORE QUESTIONS

yvre · Post by **yvre** » Tue Sep 22, 2009 7:48 am

Hi guys.

We are putting a MS1 Extra in a drag car, without using a relay board, as it was not needed.
(original thread is in the Forced Induction forum: http://www.shoptalkforums.com/viewtopic ... sc&start=0)

However, we would like to be able to remove the engine from the car easily, and also have a place where we can centralize all wires (injectors, TPS, sensors, etc…). So we are thinking of using some kind of plug/connector between the ECU and the engine.

Has anyone ever used something similar?
Any idea where we could find this kind of thing (audio equipment maybe)?
Also, do you see any potential problem/issue?

Thanks for the input.

Yves.

Post by **david58** » Tue Sep 22, 2009 8:59 am

http://www.whiteproducts.com/connectors.shtml
How many wires are you working with here. The only problem is the ALT wire.

Chip Birks · Post by **Chip Birks** » Tue Sep 22, 2009 1:52 pm

I did mine that way, though I didn't do it to any of the factory wiring, just all of the EFI. I put a plug on my firewall, it makes engine removal a snap, not to mention engine replacement. I just bought a simple plug that had 15 spots on it and used that. I initially bought a 15 and a 12 and mounted both in my firewall, but discovered that I really only needed the 15, for the sensors and such that I ended up using. So the 12 now just sits empty.

This is an older picture, but you can see the plug on the right side.
I just bought it from a computer store, it was like 7 bucks with wires precrimped into it. I just spliced mine onto those.
Chip

raygreenwood · Post by **raygreenwood** » Tue Sep 22, 2009 4:01 pm

This is a great method....having a sub-connector. Every EFI system should be done this way.

But....Do not use home or ...as I call them..."land" computer terminals and plugs for this. They do not work well long term in an automotive environment. All OEM's found out about this early on. This is why "most" serious automotive pin and receptacle designs are totally different from anything used in normal land based computer. Those do not have to hold up to water, oil, heat...and worst..vibration.
There are a jillion plugs out there in the automotive world available. Some better than others...but almost all are safer long term for an auto than what is used on office computers.

if you only drive your car a few thousand miles per year and rarely disconnect anything....then whatever. If this is even close to a daily driver...get the right thing or you can unexpectantly be walking when you least need to. Ray

miniman82 · Post by **miniman82** » Wed Sep 23, 2009 7:38 am

Do you have BMW's in Belgium? They have a nice bulkhead pass through connector that would work really well for something like that, and you could get it from the junkyard for next to nothing.

yvre · Post by **yvre** » Wed Sep 23, 2009 9:40 am

miniman82 wrote:Do you have BMW's in Belgium? They have a nice bulkhead pass through connector that would work really well for something like that, and you could get it from the junkyard for next to nothing.

Yes we do... We're neighbors counties you know...

Thanks everybody for the answers - shouldn't be difficult to find something that works.

raygreenwood · Post by **raygreenwood** » Wed Sep 23, 2009 12:01 pm

Great idea. I "think" some of the late 90's and early 00's WC VW's also have a firewall pass through plug for the ECU that may work. Ray

WickedWagens · Post by **WickedWagens** » Wed Sep 23, 2009 8:32 pm

try these

http://www.route66supply.com/store/page19.html
http://www.diyautotune.com/catalog/weat ... p-364.html

I found a few more before. Just search for "automotive bulkhead connector"

raygreenwood · Post by **raygreenwood** » Thu Sep 24, 2009 5:18 am

Those are sweet...but look carefully at the pin type, especially the female side. Some of those ...like the top 3 or so with round pins are not suitable for fuel injection. I can see enough detail on the eight pin models to know what the female connector looks like.
There is a reason that virtually every OEM uses a dual cantilever female connector. Ray

WickedWagens · Post by **WickedWagens** » Thu Sep 24, 2009 7:05 am

WickedWagens wrote:http://www.diyautotune.com/catalog/weat ... p-364.html

What about this one Ray?

raygreenwood · Post by **raygreenwood** » Thu Sep 24, 2009 12:30 pm

I can't see the pins on that one.
What you are looking for at best...is dual cantilever connectors. At worst...single cantilever connectors and then keep an eye on them.

Here is the difference. Round male pins like you see on molex plugs and square pins like you see on "home" computer stuff...have matching female connectors. Inside of these...on the round female plugs you usually see a single crimp midway down, or a circular slot...with a bent in or tabbed section that applies spring force to the male pin.
The problem found with those is that vibration and multiple plugging and unplugging...make the crimped-in grip tab areas...loose. Add heat expansion to that and you get a very unreliable system that has lots of nearly untraceable faults as it ages.

GM had that problem all the way through the 80's and 90's with the weatherpack system.

The answer to this, was the "dual cantilever female spring terminal. This is used from L-jet on in 1974 to present in almost all injection. It uses a finger or leaf on each side of a flat or square male pin...with each finger pressing inward with equal spring pressure. Instead of using a crimp in each finger to produce that spring rpessure it uses a real leaf spring installed on the female terminal. In this manner....no amount of vibration or heat will cause poor connectivity.

Mind you...plug and seal wise....and quality of build wise, weatherpack is second to none.
GM refused to pay the patents to AMP like all other manufacturers and embarked on a decade long process of making dozens or more variations of female connector...most with a single cantilever female terminal.

Now...the single cantilever terminal is pretty good. Not nearly as good as a dual cantilever...but much better than crimped tubular male and female terminals. The wear and heat expansion problems only really start to affect the single cantilever terminal when it has been plugged and unplugged alot, has high milage and long vibration periods or see's excessive heat or all combined. This is because the un sprung side of a single cantilever terminal eventually loses enough tension or wears enough that the single spring leaf on the other side cannot take up the slack.
This is why GM had tons of problems through the 80's and 90's with cars in the 70k+ mileage ranging....arriving at the dealer with reports of mysterious running problems....and they just cannot sem to reproduce the glitch.

That being said....either weatherpack has taken advantage of AMP patents that have expired...or finally started working well with others. Weatherpack is making terminals in the past few years that are even found on some new VW and Audi products injection systems.
My 2006 Jetta has injector plugs that are weather pack. They are also dual cantilever. Don't know if they are manufacturing under license or not.

Should this matter? If your car is just a toy that sees a few races and occasional driving...probably not. Though eventually older style weatherpack terminals will start causing issues that are hard to trace.
But....if its a daily driver and you use it to get to work...or carry the family in...or drive through areas you would not want to have break downs in....I would look to make sure I get what is considered the world wide standard. Just use what is used on any TUV certified European car (and most Japanese cars)...and you will be sure.

Also many newere cars can get away with some issues with terminals. On segments of the system where equality of resistance is critical...like injectors....you can't get away with sloppy connections. On single point sensors like CHT, water temp ambient air...sure...as long as its not broken connectivity and just an oddity of resistance....the down stream multiple 02 sensors and hot-wire mass air systems and plenty of logic control can work aropund a few cheap plugs.
If yoru system does not use all of that....get the most reliable plugs you can. I say this because I watch people busting their humps tuning around odd variances that could easily be caused by poor connectors. Ray

yvre · Post by **yvre** » Thu Sep 24, 2009 2:39 pm

Well that's a detailed answer - thanks.
OEM Double cantilever for best performance and reliability then.

Now... we are trying to finish the wiring on the car, but still have a bunch of questions... (remember, we're both useless at electrics/electronics

)

1) We are using an LM1 instead of an LC1, so we need to use the the 3 wire stereo aux plug. According to the LM manual, there are 2 analog outputs and 1 ground. Which output do we need to connect to MS , what do we do with the 2nd one and how/where do we ground?

2) We lost the CD (yeah I know

) we received when we bought the MSExtra kit from Philip Ringwood/ExtraEfi.co.uk, so I downloaded it again from his site. But he had already burned a base setting to the ECU. Can I just fetch all the data from the ECU in order to get a new base msq file?

3) I created a new msq file anyway while reading the manual and working offline (I set the constants, codebase and output functions, etc etc.)
I saved it on my PC yesterday, but when I tried to open it today nothing happens in Megatune=; why doesn't it want to open my saved settings?

I'm sure I'll post more dumb questions later so please bear with me...

yvre · Post by **yvre** » Thu Sep 24, 2009 2:41 pm

double post

yvre · Post by **yvre** » Thu Sep 24, 2009 2:45 pm

Everybody loves a pic...

yvre · Post by **yvre** » Fri Sep 25, 2009 1:17 am

Been surfing the MS forums all morning (shhh, don't tell my boss) and found this:
"Before starting to enter settings it is essential that you connect your computer to the Megasquirt to fetch the standard settings (or load in a default .msq)"

Edit: BUT!!! Will I be able to read the msq loaded in the ECU (which is 2 years old) with the 029y4 version that is available for download???