C3 Vette Registry - The Best Resource on the Net for C3 Vettes! C3 Vette
Forums -> All Vettes Discussion
Not Logged In! Login or Register!  Users Online: 25 / Help 
Features  Find C3 Parts on ebay in only 2 or 3 clicks!  | Add YOUR C3 to the Registry

Supporting Vendors
CorvetteClothing.com
Bair's Corvettes
Mid America Motorworks
VetteBookStore.com
Volunteer Vette Products

C3 of the Month
None Current
Enter Yours Today!
Online C3 Show
13
C3s are Registered

Vanity Plates
C3 SHARK
sharkc3
Featured Links

Buy Now
The Corvette Dynasty (Hardcover)
The Corvette Dynasty (Hardcover)


Corvette Fifty Years (Hardcover)
Corvette Fifty Years (Hardcover)


Corvette Magazine - $19.99 for 8 issues
Corvette Magazine
Only $19.99 for 8 issues


The Corvette Factories: Building America's Sports Car (Hardcover)
The Corvette Factories: Building America's Sports Car (Hardcover)



| Hide Signatures and Profile Pics

 New Topic New Topic Post Reply Reply New Poll New Poll Search     Search Page [1] 2  
8/25/08 9:54pm - Original Message: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
anyone know if the 1995 corvette should generate a PCM Error code (such as DTC 16, 41 or 42) if the ICM or Ignition Coil is bad ???  My 95 will crank but not start - there is no spark from the ignition coil to the optispark.  I have run the diagnostic checks from the service manual and it indicates one of these two components are bad.  But before I replace (since I cannot return the parts) I am curious why I would not have one of the above PCM error codes.  All those codes relate to ignition or low voltage.

____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
 
Support C3VR!
Suport our advertisers
8/26/08 12:45am - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449


Not having a trouble code is common...it has to "see" a specific problem, for a specific amount of time, to set a code.
I'd say yer Opti-Spark is sparked out...

The ICM and the coil are one unit...if ya replace one, the other comes along for the ride!

The Opti-Spark sux...it's usually best to just replace the whole dang thing, and be done with it. The ones you can buy now have all the upgraded stuff in them, so they survive much better.
Stingrayjim had/has a hook-up on them, I think, as far as a good source to get them from.

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
8/26/08 4:28am - Reply: 'C4 Ignition Error Codes'
tuxblacray Lifetime Member
Lifetime Member
- Send Private Message


Greensburg, IN - USA

Vette(s):
Previous: 1984 Silver / Charcoal Coupe, 1988 Maroon Coupe / 1989 Artic White / Mod. Red Int. Coupe, Present:1976 Stingray Black / Black, Auto, 350 slightly modified (355 hp) Luxor Wires Redline Tires. / 2001 Speedway White Vert, Torch Red Int, LS1, Auto.

Joined: 9/24/2003
Posts: 5174
One thing I might add is to check your water pump while your there. It is very common for the water pump to begin leaking and cause the distributer to get wet and fail.

The distributer is also a booger to remove. Good Luck Kerry!

____________________________________
Tuxblacray: She's Back In Black! Check out my pics @ My Link


(Click on image to see a bigger version)


 Reply Reply  Quote Reply w/Quote
8/26/08 8:27pm - Reply: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
The water pump and optispark were new with the engine rebuild 10 months ago and since then, the engine has less than 500 miles.  If the optispark was gone, I should still have a spark from the coil into the optispark.....Right??

____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
8/26/08 10:41pm - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
What th heck d'ya mean?

If there is an issue within the distributor(the opti-spark unit), the coil will not fire at all, depending on the failure mode. The optical wheel inside the distributor has to "trip", or signal the the PCM to fire the coil . Then the PCM signals the ICM(ignition control module) thru the EST(electronic spark control) by grounding the primary circuit that supplies the voltage to the coil. This collapses the coil field, which causes the coil to sparkle.
If I am a-reading you correctly, yer coil ain't firin, right?
Since the opti-spark was just recently replaced(which don't mean diddly anyway), how about the ICM/coil assy? Was it replaced at the same time?
I'd want to check and see if the PCM was grounding the circuit for the ICM, and if it is, then you know the opti is working, and the problem is most likely the ICM/coil.

If you have a test light, try this...
At the ICM connector, you should have a white wire, a white/black stripe wire, a pink/black stripe wire, and a solid black wire. The solid black is the ground for the module, so it should be grounded on the engine block.
The wire we want to check is the solid white wire. Remove the coil wire from the distributor, and place it close to something that will be a ground, like the block, or a bolt on the water pump. With the key "On", and your test light connected to a good ground, probe the white wire quickly...just a touch and release. IF the ICM is good, the coil should fire as you touch/release the test light to the white wire. If it does not, do it a few more times, just to be sure. If ya really want to be sure, grab the coil wire with your hand...you'll KNOW if the coil is firing...
If the coil does fire like that, then the problem is gonna be in the opti=spark unit, or the PCM. OR...the dang ground wire. Remember, it's STILL a Corvette, and grounds are important...

If you have a good voltmeter/digital multi-meter, you can monitor the white wire for a ground from the PCM while cranking the engine. Just set the meter for DC volts, and connect it to the white wire, and crank the engine. The meter should fluctuate from high to low voltage if the PCM is grounding the circuit as it should.

Did this just happen all of a sudden, or did it start runnin like crap, and then die?

another thought just floated into me haid...the tach filter could cause a no-spark, too, if it was grounded out...might see if you can unplug that, and give it a try...


oh yeah...one more thing....it's prolly a silly question, but has ya checked the fuses? A blown INJ fuse would also dis-able the ignition system...Adams' Apple2008-08-27 06:41:32

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
8/27/08 10:59pm - Reply: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
Well, no loose wires, Clap forced the ICM to ground with the good old paper clip trick .... and no spark Thumbs%20Down,  test light indicated a good ground on the ICM pigtail Thumbs%20Up, also have a good ohm test of the wire from the PCM to the ICM Thumbs%20Up.....The coil metal casing has rust on it and Joel says thats a good indication the coil has started to magnetize which prevents it from storing a charge ...... so, off to the parts store to get a new ICM and Coil $$$$ (well, not really, going to cheat and have my son get it from the Hummer dealer where he works....should save us a few coins at dealer cost Big%20smile).  Will get the new parts in on the weekend and let y'all know how it works out.
Now while I wait, time to move over to the weatherstripping on the C3 back window.....then back to finishing the C4 interior.....always something


____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
8/30/08 11:16am - Reply: 'C4 Ignition Error Codes'
jimiam
Former Member
- Send Private Message


Memphis, TN - USA

Vette(s):
1981 Red 1993 Black Rose

Joined: 2/16/2007
Posts: 134
 I'd keep in mind, the coil isn't going to fire if the opti IS NOT getting a signal to the ECM, which in turn signals the ICM to fire.
 Joel is really sharp on this stuff, but on my '93 each time I cleared the error codes and tried to start the engine, the error codes would set again regardless of how long I let the engine turn. He's also right on about how long that opti has been in service not meaning diddly. I replaced one at about 62k miles and then again 3k miles later. (as well as one that was bad out of the box) Here's hoping your problem lies elsewhere, but I'm not optimistic.
 


____________________________________

(click to see a bigger image)
 Reply Reply  Quote Reply w/Quote
8/30/08 1:13pm - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
Kerry's car isn't setting any codes, tho...it just won't fire. The "scratch test" showed the ICM/Coil isn't firing, pretty much eliminating the Opti as the source of the problem. IF the coil was firing during the scratch test, then we'd be looking at a PCM, wiring, or Opti issue. He tested the wire from the PCM to the ICM/coil already, and it was OK.
Opti issues will normally set codes, but a bad coil won't, in most cases, as the PCM doesn't monitor whether or not the plugs are firing. Adams' Apple2008-08-30 14:20:36

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
8/30/08 3:14pm - Reply: 'C4 Ignition Error Codes'
jimiam
Former Member
- Send Private Message


Memphis, TN - USA

Vette(s):
1981 Red 1993 Black Rose

Joined: 2/16/2007
Posts: 134
 I'll file that away for the future too Joel. That's why I enjoy reading your posts. Thumbs%20Up 

____________________________________

(click to see a bigger image)
 Reply Reply  Quote Reply w/Quote
8/31/08 8:10am - Reply: 'C4 Ignition Error Codes'
tuxblacray Lifetime Member
Lifetime Member
- Send Private Message


Greensburg, IN - USA

Vette(s):
Previous: 1984 Silver / Charcoal Coupe, 1988 Maroon Coupe / 1989 Artic White / Mod. Red Int. Coupe, Present:1976 Stingray Black / Black, Auto, 350 slightly modified (355 hp) Luxor Wires Redline Tires. / 2001 Speedway White Vert, Torch Red Int, LS1, Auto.

Joined: 9/24/2003
Posts: 5174
During Kerry's wait on the ICM module for kicks and giggles I would be taking each grounding points loose and inspecting, cleaning and replacing them.There are many and they should be better named as corrosion points rather than grounding points.

My last C4 opti / codes issues were like a witch hunt chasing through the codes / firing issues.
Each time I would clean some of the grounded areas it seemed to get better. (and I believe it was)

I finally traced the issue to an after-market security system that had been installed under the dash. I had not noticed it until on day I just happened to notice the light on the top of the dash was slightly different than others I had seen..... What if...? I disconnected it and found everything to be in working order afterwards. (then and now) Sooo, Bubba had struck in his quite undetected manner. Although I believe that it was no fault of his own that the after-market security system had died.

But what I did find that most likely had prompted the change in system I believe was the drivers door lock harness had been severed by the window track coming loose. Once I repaired the harness everything was back to normal working OEM condition. (OEM security system included)

Becuase in reality what I thought was an ECM then BCM problem was really something relative instead. I had a door lock keyfob problem that I had never considered to be relative.... but I was WRONG!

Moral of this story..... Every Freakin Thing in these cars is connected electronically to each other. Sooo if you may have to hunt deeper that the obvious to find the root cause. (Hence the saying "Thingz are not always as they seem!")

Hang in there Kerry my friend I lit a candle and placed it on my Corvette Alter for you my friend!

____________________________________
Tuxblacray: She's Back In Black! Check out my pics @ My Link


(Click on image to see a bigger version)


 Reply Reply  Quote Reply w/Quote
8/31/08 12:59pm - Reply: 'C4 Ignition Error Codes'
spielman5 Lifetime Member
Lifetime Member
- Send Private Message


ANCHORAGE, AK - USA

Vette(s):
1965-327 coupe, 1968-small block coupe, 1969-427, 1971-454 coupe and currently a 1976-ZZ4 coupe reborn again,and hotter than ever.. Add a 1996 CE LT-4 for backup

Joined: 10/12/2004
Posts: 2193
Me too Kerry, I ll open that beer and wish ya luck..

____________________________________


   "I Love all Corvettes! LifeTime Member #60..Terry"
 Reply Reply  Quote Reply w/Quote
8/31/08 7:52pm - Reply: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
Well, another long afternoon and no success.....changed out the ICM and Coil with new GM Delco..... but still have the same "Crank no start" problem.  From the look of the old coil and ICM, they were original and needed replacing.  The coil was rusted and the ICM heat sink silicon gel was all dried up to a powder.

Anyways....following the SM diagnostics, the ICM connector has 12 volts in on two wires, solid ground on the third and the fourth wire has good continuity to the PCM. 
Did the same checks on the Opti connector and everything is what the SM indicates. 
Also pulled the ignition coil wire and inspected -- it was new last year and still looks new....also tests out with 5300 ohms. 
Also did the SM test to jump the two "B" wires for the coil and test the "A" with the test light while cranking the engine.....this is suppose to cause the test light to flash, but NO FLASH....so guess what, the SM says either the ICM is bad or the ICM connector is bad -- no way all their tests said everything was good......HMMMMMMMMMMMM

Also cranked the engine and did Stingray Jims wire jiggle dance......no start.

Also rechecked every fuse with the DVM (just in case I had a sneaky non-visible break)....they all tested good

Here is the last thought.......the ONLY thing I did after the last start (Yah, I know, I just remembered it today as I was thinking through all the possible causes) was I got a keyless entry fob from Corvettes of Dallas.  (it was free as they did not have a working one when my son bought the car).  anyways, we tested it at the dealer and it programmed their 95.  When I tried to program my 95, I could not get the computer to enter into programming mode (light on the diagnostic center never came on).  I tried it several times but gave up thinking it needed the power door lock connectors plugged in (have all the door panels off to redo the weather stripping).

So my question is, could I have somehow disabled the start programming because I could not get into the keyless entry program???? I am grasping for anything now.

Tux, tomorrow I plan to connect the power door locks (power windows and rear hatch were always connected because I needed those) JUST TO SEE WHAT HAPPENS......NO WAY it should matter because I was driving it before with the door panels and power locks disconnectd.....but hey...its a vette with an attitude.

TUX....GET BUBBA OUT OF HERE.....I found his after market security under my dash also a few months ago.   A key in a cylinder with two wires going somewhere.  anyways, the car worked with it but who knows now.

Thanks everyone for your continued suggestions  (and no, I am not frustrated enough to pull the Opti or replace the PCM .... yet)
Reds82CE2008-08-31 16:57:16

____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
9/1/08 12:14am - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
Uh oh....you may have a CCM that took a doo-doo.
I just thought of that, since you mentioned the key thing. The Central Control Module, if bad, WILL give you a no start, AND, it will not let you program the key/fob for the security system. But then...it would also keep it from cranking, too...
You may have disabled the starting thingy when you attempted the re-program for the key...might as well go ahead and plug all that crap back in, and give it another shot.
I had a '96 at the shop that had pretty much the same issue, and testing on it showed the CCM was shot. We got a new CCM and installed it, but STILL had to send it to the dealer to get the danged key programed.
Hopefully yours is not like that...

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
9/1/08 3:34am - Reply: 'C4 Ignition Error Codes'
spielman5 Lifetime Member
Lifetime Member
- Send Private Message


ANCHORAGE, AK - USA

Vette(s):
1965-327 coupe, 1968-small block coupe, 1969-427, 1971-454 coupe and currently a 1976-ZZ4 coupe reborn again,and hotter than ever.. Add a 1996 CE LT-4 for backup

Joined: 10/12/2004
Posts: 2193
Would a bad battery in the key fob do this??

____________________________________


   "I Love all Corvettes! LifeTime Member #60..Terry"
 Reply Reply  Quote Reply w/Quote
9/1/08 2:42pm - Reply: 'C4 Ignition Error Codes'
tuxblacray Lifetime Member
Lifetime Member
- Send Private Message


Greensburg, IN - USA

Vette(s):
Previous: 1984 Silver / Charcoal Coupe, 1988 Maroon Coupe / 1989 Artic White / Mod. Red Int. Coupe, Present:1976 Stingray Black / Black, Auto, 350 slightly modified (355 hp) Luxor Wires Redline Tires. / 2001 Speedway White Vert, Torch Red Int, LS1, Auto.

Joined: 9/24/2003
Posts: 5174
Kerry, your skeerin me... I had tried to put this C4 episode outta me lil pea brain an now it's s-l-o-w-l-y coming back (OUCH).

Okay did your car every so often happen to lock itself? That is the one thing I fergot to mention. All of your symptoms are the same as whut mine were (cept that one).

I also borrowed a friend keyfob to program the car to see if it was gonna werk prior to buying a keyfob. Primarily because I I was struggling with the "other" electrical issues simultaneously. Like yours it wouldn't work. That is how I found the severed harness. I couldn't figure out why is wasn't working until I removed the door panel and said " Oh my God..... ain't that just grand!"

I can tell you that in 94 they made the harness specific for that car. Finding a used one was impossible so I painstakingly repaired the old one 1st rather than donating $150.00 to the stealership to see if it worked. Fortunite for me it worked fine afterwards.

I believe that you will be able to locate a used harness coil for your car with success if you find that yours happens to be damaged as well. I might note here that I had no window problems (up / down) to indicate something had gone wrong. It did appear though that the root cause of the harness coil having been severed was it had came loose and manage to slide over into the tract.

Candle still burning Bro......


____________________________________
Tuxblacray: She's Back In Black! Check out my pics @ My Link


(Click on image to see a bigger version)


 Reply Reply  Quote Reply w/Quote
9/1/08 3:57pm - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
If I remember right, when programing the key/fob, it will cycle the door locks, so ya might need all the stuff connected.
Does your key have the little resistor pellet in it?

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
9/1/08 5:10pm - Reply: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
Yes, the key has the pellet, but both sets of keys give the same "Crank-no-start".

Reconnected all the door electrical connections....still no change.

So, I checked all the codes in the computers again, CCM 1.2, 1.3, 1.4.  all these settings are normal and indicate the CCM is communicating to all the sensors correctly.  In 1.3 mode, I could see the CCM turning on/off sensors/lights.  So this tells me the CCM GROUNDS ARE GOOD.  Also verified again there are no stored DTC codes in the PCM/ECM/ABS/TCS/DERM. 

Back to looking for bad connectors by doing a continuity test on all the wires....someone tell me there is an easier way
Reds82CE2008-09-01 14:18:04

____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
9/1/08 8:01pm - Reply: 'C4 Ignition Error Codes'
Reds82CE Lifetime Member
Lifetime Member
- Send Private Message


McKinney, TX - USA

Vette(s):
1982 Collector Edition, Silver-Beige metallic, 40000 miles and counting. 2015 Z51 Red Convertible

Joined: 4/8/2005
Posts: 182
All my grounds from the PCM are good.  Pulled the PCM connectors off, connected the test light to each ground pin and light came on.

Also did a continuity test on the Opti 4 wire connector back to the PCM:
B2 - Low Resolution Signal Input was 3.4 ohms
B3 - Distributor Reference Low Signal was 2.0 ohms
B14 - Distributor Ignition Feed was 0.6 ohms
B20 - High Resolution Signal Input was 0.8 ohms

I can't find anywhere in the SM that tells me if B2 and B3 should be that high....ANYONE KNOW????

According to the SM, I still need to test the following which causes a crank no start:
B2 - Low Resolution Signal (but this should set DTC 16)
B3 - Distributor Reference low signal (No DTC set)
B5 - Ignition Control (should set DTC 41 or 42 and I installed a new coil an d ICM so can rule this one out)
B14 - Distributor Feed (No DTC set)
B15 - PCM Battery Feed (No DTC set and has something to do with the Oil pressure switch)
B30 - PCM Ignition Feed (No DTC set)

The  test for B2 is "TEST CONNECTOR 'A' DISTRIBUTOR 'A' " and B3 uses "D"..............IS THIS JUST A CONTINUITY TEST??? Same as I did above?


____________________________________
Lifetime Member #58
Our 82CE

(Click to see a larger version)






 Reply Reply  Quote Reply w/Quote
9/1/08 9:39pm - Reply: 'C4 Ignition Error Codes'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
B2 & B3 appear to have high resistance. As far as I know, they should read the same as the other two wires, UNLESS there is a "filter" in-line on them. I don't have diagrams here for the '95, but I can get what I have at the shop tomorrow...

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
9/1/08 11:16pm - Reply: 'C4 Ignition Error Codes'
Gale Banks 80 Lifetime Member
Lifetime Member
- Send Private Message



Vette(s):
1980 with a Banks Twin Turbo 1969 Convert Big Block 1996 Grand Sport Convert

Joined: 9/8/2005
Posts: 241
 As the owner of an Lt4 with 50k and starting ton leave a small Puddle of Antifreeze I have been fowwoling this one with great Interest. The big Waterpump-Optispark-Plugwire Replacement is just around the corner. All the advice given above is way above my Head so all I can do is agree as it all makes sence to me. The only thing I can add is to give Gordon Killebrew a Call I assume If you guys know as much as you do you know who He is. For those here that don't He Teach's Troubleshooting Class for C4's. He is the Guy who rewrote the Shop Manuels for GM. If a 95 won't fire cause the left Rear Tire is low and the passenger Seatbelt is undone wile the Hood is open He is the Guy who will know. www.gordonkillebrew.com 

____________________________________
My Car...PIC 1     PIC 2
 Reply Reply  Quote Reply w/Quote
 New Topic New Topic Post Reply Reply New Poll New Poll Search     Search Page [1] 2  
 Forums -> All Vettes Discussion
(Moderator: Adam Wartell, Norsky, Adams' Apple)
 

 
Official C3 Vette Registry Community:
Home | Forums | Email | Who's Online | Clubs | Events | Member Stats

Other Official C3 Vette Registry Areas:
Members | Research | Shop | My Account | About C3VR
 

Corvette is a registered trademark of the General Motors Corporation(GM) & Chevrolet Motor Division. Vette Registries, LLC is responsible for all site content (except for member submitted content or where otherwise noted) and does not claim or imply that Chevrolet or GM is responsible for Official C3 Vette Registry content. Vette Registries, LLC is independent from GM and is not affiliated with, sponsored or supported by GM.  Copyright/trademark/sales mark infringements are not intended, or implied and are in fact used to support GM, Chevrolet and Corvette

Official C3 Vette Registry content is Copyright 2001-2017, Vette Registries, LLC. Content may not be reused without written consent. All Rights Reserved. NS

Corvette (Vette) Model Years on this site: 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 30