Yea. Whats up with the different color wires??
HEI coils- pickup coils
Thread Starter
Burning Brakes
Joined: Nov 2000
Posts: 810
Likes: 4
From: Austria
HEI coils- pickup coils
hi
maybe someone remember me, i still fight against my hunting idle
i read in my shop manual the following
if you have a ign coil with a yellow wire, you MUST use a pickup coil with a yellow connector...
if you have a ign coil with a different color, i think red (or maybe white)
any color of the pickup connector , EXCEPT yellow, is ok
can somebody explain this??
where are the differences in the combinations
thank you
maybe someone remember me, i still fight against my hunting idle
i read in my shop manual the following
if you have a ign coil with a yellow wire, you MUST use a pickup coil with a yellow connector...
if you have a ign coil with a different color, i think red (or maybe white)
any color of the pickup connector , EXCEPT yellow, is ok
can somebody explain this??
where are the differences in the combinations
thank you
Drifting
Joined: Apr 2003
Posts: 1,292
Likes: 2
Its all about polarity, the pickup coil is generating an AC signal all right, but the spark coil is doing the same in sync. The flux generated interferes.
(would explain further but it is 1.35 am- need to go to bed)
(would explain further but it is 1.35 am- need to go to bed)
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by britvette
Its all about polarity, the pickup coil is generating an AC signal all right, but the spark coil is doing the same in sync. The flux generated interferes.
(would explain further but it is 1.35 am- need to go to bed)
(would explain further but it is 1.35 am- need to go to bed)
TTT
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Originally Posted by corvette90
hi
maybe someone remember me, i still fight against my hunting idle
i read in my shop manual the following
if you have a ign coil with a yellow wire, you MUST use a pickup coil with a yellow connector...
if you have a ign coil with a different color, i think red (or maybe white)
any color of the pickup connector , EXCEPT yellow, is ok
can somebody explain this??
where are the differences in the combinations
thank you
maybe someone remember me, i still fight against my hunting idle
i read in my shop manual the following
if you have a ign coil with a yellow wire, you MUST use a pickup coil with a yellow connector...
if you have a ign coil with a different color, i think red (or maybe white)
any color of the pickup connector , EXCEPT yellow, is ok
can somebody explain this??
where are the differences in the combinations
thank you
Also the PU coil does produce a sine wave with an amplitude of about 2.5 to 3 volts depending on RPM. That signal fires the HEI ignition module which in turn toggles the ignition coil to fire it. I don't see how the sine wave signal from the PU coil can have any interference with the coil firing or with the magnetic flux that is created by the coil when it saturates and then discharges. At least I can't remember any of that from my EE classes
damn I am getting old 
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Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
[QUOTE=tjwong]In all my years working for GM and replacing lots of defective pick up coils I have never seen a pick up coil with a yellow wire. All of the ones I replaced used a green and white wire in the large and small cap distributors. I don't recall seeing something in the manual about a yellow wire but I will certainly check it now. Can you state what year manual and the page that you are looking in. I have most of the C4 GM manuals here.
[QUOTE]
The Corvette Shop Manual for the 86 makes a point of using the correct coil for the pick-up coil installed. The coil and pick-up coil wire colors must be correct for each other, according to GM.
From what I've been able to learn it is a polarity issue and it may be specific for the 85-89 Vette. I wonder, too, if mis-matched colors can effect module life.
Jake
[QUOTE]
The Corvette Shop Manual for the 86 makes a point of using the correct coil for the pick-up coil installed. The coil and pick-up coil wire colors must be correct for each other, according to GM.
From what I've been able to learn it is a polarity issue and it may be specific for the 85-89 Vette. I wonder, too, if mis-matched colors can effect module life.
Jake
Thread Starter
Burning Brakes
Joined: Nov 2000
Posts: 810
Likes: 4
From: Austria
thanks everyone for chiming in
at tjwong..heres the page;: its in my 1990 shop manual, 6E3-C4-4 and the following page....at the bottom...
another thing, its stated on page 6E3-B-3, on top of the page
if engine starts, but then immediatly stalls, open distributor, set timing connector..if engine the starts and runs ok, replace pickup coil
this is a bit my situation..if car sat overnight, i start, engine fires short, than stalls..then i start again coax a bit with the gas, the engine runs with rough idle....if i open the EST conn, the engine starts , dont stall and idle much smoother...
could this lead to a defective pickup coil???
many thanks
at tjwong..heres the page;: its in my 1990 shop manual, 6E3-C4-4 and the following page....at the bottom...
another thing, its stated on page 6E3-B-3, on top of the page
if engine starts, but then immediatly stalls, open distributor, set timing connector..if engine the starts and runs ok, replace pickup coil
this is a bit my situation..if car sat overnight, i start, engine fires short, than stalls..then i start again coax a bit with the gas, the engine runs with rough idle....if i open the EST conn, the engine starts , dont stall and idle much smoother...
could this lead to a defective pickup coil???
many thanks
Thread Starter
Burning Brakes
Joined: Nov 2000
Posts: 810
Likes: 4
From: Austria
Originally Posted by corvette90
thanks everyone for chiming in
at tjwong..heres the page;: its in my 1990 shop manual, 6E3-C4-4 and the following page....at the bottom...
another thing, its stated on page 6E3-B-3, on top of the page
if engine starts, but then immediatly stalls, open distributor, set timing connector..if engine the starts and runs ok, replace pickup coil
this is a bit my situation..if car sat overnight, i start, engine fires short, than stalls..then i start again coax a bit with the gas, the engine runs with rough idle....if i open the EST conn, the engine starts , dont stall and idle much smoother...
could this lead to a defective pickup coil???
many thanks
at tjwong..heres the page;: its in my 1990 shop manual, 6E3-C4-4 and the following page....at the bottom...
another thing, its stated on page 6E3-B-3, on top of the page
if engine starts, but then immediatly stalls, open distributor, set timing connector..if engine the starts and runs ok, replace pickup coil
this is a bit my situation..if car sat overnight, i start, engine fires short, than stalls..then i start again coax a bit with the gas, the engine runs with rough idle....if i open the EST conn, the engine starts , dont stall and idle much smoother...
could this lead to a defective pickup coil???
many thanks
nobody? dont leave me in the dark
