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Re: hei cap orientation [message #328415 is a reply to message #328379] Sat, 20 January 2018 20:18 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Registered: June 2008
Location: S. Ontario, Canada
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Senior Member
Trevor,
The 4 wire module on the firewall is the knock sensor interface between the engine knock sensor and the engine control module.

The 7 wire module inside the distributor detects the trigger from reluctor and amplifies the signal for the ECM. It also takes the spark trigger from the ECM and drives the ignition coil.

These drawings for the EBL system might help. From the pin numbers, it looks like TurboCity system used the same GM 7747 ECM

http://www.dynamicefi.com/EBL_Drawings.php


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: hei cap orientation [message #328416 is a reply to message #328379] Sat, 20 January 2018 20:53 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2276
Registered: June 2008
Location: S. Ontario, Canada
Karma: 3
Senior Member
There is quite a bit of good GM EFI information in this write-up. It might help you understand your EFI and spark control system.

http://www.gmceast.com/technical/Swartzendruber_Generic_TBI_SlidesNotes.pdf


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: [GMCnet] hei cap orientation [message #328446 is a reply to message #328416] Sun, 21 January 2018 13:30 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Sorry you do have the Dist control
DJ Eberheart in Oregon should be able to assist you
Should you need his contact # call our office
I'm traveling to a RV Parts Show in Dallas, TX

On Sat, Jan 20, 2018 at 7:12 PM Bruce Hislop wrote:

> There is quite a bit of good GM EFI information in this write-up. It might
> help you understand your EFI and spark control system.
>
> http://www.gmceast.com/technical/Swartzendruber_Generic_TBI_SlidesNotes.pdf
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
> Hubler 1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: hei cap orientation [message #328524 is a reply to message #328379] Tue, 23 January 2018 01:19 Go to previous message
cadelec is currently offline  cadelec   Australia
Messages: 303
Registered: September 2011
Location: Brisbane Australia
Karma: 1
Senior Member
thanks for everyones input
today i solved the running rough .
i am rusty on working on engines and need to get up to speed, typically i bypasssed the critical first steps of look at the obvious instead i suspected the items i had no understanding on.
this coach has been here for 4 years and i would periodically go and start it up.
at one stage it started running rich
then the fuel pump then passed away so it sat for a little longer about 6 months
i finally got a new pump and it started but was running rough.
as it is not registered i cannot take it out for a test drive
6 months passes again and it is time to start the registration process
i need to get it weighed so i run the gauntlet and drive about 2 kilometres to the weighbridge
it backfires all the way but i get there and back
so i google backfiring and read that maybe a valve is stuck open
so istart to pull plugs to do a compression test and i noticed the wires on the cap problem
so i stop and post my original question on this site
this takes me on a tangent of trying to learn everthing about who the EFI works
this has been a good learning curve for me as i have a bit better knowledge as to which components are which
on sunday i was talking to a mechanic friend and he tells me to get an ALDL cable so i can see what is going on in the computer for in the future (i ordered one yesterday)
he also says that last time he saw me start it up it was running very rich and maybe the plugs are fouled
today finally i pull plug #7 and what do you know it is oiled up
get 8 new plugs now runs like a champ

whats the saying keep it simple stupid



Trevor Brisbane Australia Siesta Koala 76 Edgemont (old Bobby Moores) 71 Cadillac Eldo Convert 58 Cadillac Eldorado Brougham Project
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