Sound Like An Optispark Issue?
Thread Starter
Burning Brakes
Joined: Nov 2009
Posts: 813
Likes: 0
From: Fort Worth TX
Sound Like An Optispark Issue?
Hey guys,
I've come to the conclusion that my "rattling sound" issue is directly linked to the ignition system in some way. My uncle believes that it's the ignition coil, whereas I believe it's the optispark. The car has exactly 61k miles. When it's having the issue (only on wet/humid days), it has a very rough idle, is not repsonsive at all, and when u give it a little more gas than normal, it makes this loud clicking noise that is most definitely the ignition missing. Should I replace both things? Is there a test I can run to see which I need to replace? If it is the optispark, is it worth the extra $250 for the MSD?
I've come to the conclusion that my "rattling sound" issue is directly linked to the ignition system in some way. My uncle believes that it's the ignition coil, whereas I believe it's the optispark. The car has exactly 61k miles. When it's having the issue (only on wet/humid days), it has a very rough idle, is not repsonsive at all, and when u give it a little more gas than normal, it makes this loud clicking noise that is most definitely the ignition missing. Should I replace both things? Is there a test I can run to see which I need to replace? If it is the optispark, is it worth the extra $250 for the MSD?
Melting Slicks
Joined: Feb 2010
Posts: 2,077
Likes: 72
From: Reno Nv
You can check for Opti trouble codes by jumping the #4 an #12 pins on the ALDL connector that's under the driver's side dash. Then you can read them on the dash display.
DTC # 16 and 36 are the codes displayed when the opti starts to go.
Since it's a humidity thing, you can run the car in a dark garage and use a spray bottle, set on fine mist, to spray around the wires, coil etc.
Look for the "light show". Pay close attention to the coil wire that lays on top of the waterpump.
If you plan to keep the car for a long time, the MSD is worth it (my opinion). It has a better bearing and much better cap sealing than the GM. My MSD has 20k on it, no problems.
DTC # 16 and 36 are the codes displayed when the opti starts to go.
Since it's a humidity thing, you can run the car in a dark garage and use a spray bottle, set on fine mist, to spray around the wires, coil etc.
Look for the "light show". Pay close attention to the coil wire that lays on top of the waterpump.
If you plan to keep the car for a long time, the MSD is worth it (my opinion). It has a better bearing and much better cap sealing than the GM. My MSD has 20k on it, no problems.
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
Take alook at thread. My opti failed and I got a new MSD to replace. It wouldnt start but would spudder sometimes. And I could keep it alive alitte if I hit the gas.
http://forums.corvetteforum.com/c4-t...h-the-le2.html
If you need a MSD I might be selling mine soon. It has about 60 miles on it. Im swaping to a LSx motor.
http://forums.corvetteforum.com/c4-t...h-the-le2.html
If you need a MSD I might be selling mine soon. It has about 60 miles on it. Im swaping to a LSx motor.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
You don’t have any symptoms that relates to an opti. I don’t think moisture would affect noise from the opti. And if the rotor broke, it's not going to run. And coils don’t make rattling sounds. They break down internally and cause poor or no spark.
It sounds like something is sparking or arking like perhaps a wire to ground especially since you say it happens when it's wet outside.
Open the hood when it's dark and look for something sparking, rev the engine a bit. Look closely at the coil wire where it feed thru the water pump to the top of the opti. Sometimes some a water atomizer bottle is used to spray some water lightly on the plug wires to find the problem easier.
It sounds like something is sparking or arking like perhaps a wire to ground especially since you say it happens when it's wet outside.
Open the hood when it's dark and look for something sparking, rev the engine a bit. Look closely at the coil wire where it feed thru the water pump to the top of the opti. Sometimes some a water atomizer bottle is used to spray some water lightly on the plug wires to find the problem easier.
Pro
Joined: Sep 2004
Posts: 505
Likes: 1
From: Guntersville Alabama
Keep this fact in back of your mind after you have eliminated everything else. The opti will arc and cause the engine to miss and sputter without throwing a code and moisture is the culprit. The reason is the position sensor is sending the correct signal back to the ECM. I have had two opti's fail without a single code.
93cruiser
93cruiser
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Sounds like a plug wire grounding out. Moisture will affect them in a bad way. Since it's running so bad I'd look at the coil wire itself. It may be grounding out on the block. That may make a rattle sound because the spark on it is so hot. Good luck!
Thread Starter
Burning Brakes
Joined: Nov 2009
Posts: 813
Likes: 0
From: Fort Worth TX
Keep this fact in back of your mind after you have eliminated everything else. The opti will arc and cause the engine to miss and sputter without throwing a code and moisture is the culprit. The reason is the position sensor is sending the correct signal back to the ECM. I have had two opti's fail without a single code.
93cruiser
93cruiser
This could be feasible as well. I'd really like to go MSD everything (plug wires and opti), but I just don't have that kind of cash now haha
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Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Before you make the leap and replace the opti, I would make sure it needs it before I did that work. I’m not saying the opti may not be the problem, but I think this thread is going too fast and assuming it's the opti.
Of all the symptoms I have seen and read on the Forum, I have never had anybody indicate a rattling noise. Is this noise at idle or just above. Or are you calling rattling being in drive pushing on the gas and really having pinging or pre-ignition. I would need your term of rattling defined as to exactly the conditions it happens. A lot of opti's act up and has poor running when engine reaches operating temperature. They can cause a wondering idle also.
Have you actually done what has been suggested and looked for any sparking off of the plug and coil wires. I guess I’m having trouble being sold on a bad opti because the rattling condition is throwing me off a bit and not sure how to take it.
An opti job is not cheap to do and even if doing it your self is a weekend of work. I would just make sure that’s where I need to go.
Of all the symptoms I have seen and read on the Forum, I have never had anybody indicate a rattling noise. Is this noise at idle or just above. Or are you calling rattling being in drive pushing on the gas and really having pinging or pre-ignition. I would need your term of rattling defined as to exactly the conditions it happens. A lot of opti's act up and has poor running when engine reaches operating temperature. They can cause a wondering idle also.
Have you actually done what has been suggested and looked for any sparking off of the plug and coil wires. I guess I’m having trouble being sold on a bad opti because the rattling condition is throwing me off a bit and not sure how to take it.
An opti job is not cheap to do and even if doing it your self is a weekend of work. I would just make sure that’s where I need to go.
Thread Starter
Burning Brakes
Joined: Nov 2009
Posts: 813
Likes: 0
From: Fort Worth TX
Here's what's going on:
(This only happens on occassion) When the car is idling, it starts loping and shakes pretty roughly. When I go from a stop, it shakes and then smooths once the rpms rise above 1200rpm. If I put the pedal down a bit, it makes this nasty sparking noise at a rate of roughly 10 clicks every 4 seconds, and the car becomes sluggish. The revs go up, but the car doesn't increase in acceleration at all. She runs flawlessly most of the time, but in these strange instances where this happens, it runs like crap
(This only happens on occassion) When the car is idling, it starts loping and shakes pretty roughly. When I go from a stop, it shakes and then smooths once the rpms rise above 1200rpm. If I put the pedal down a bit, it makes this nasty sparking noise at a rate of roughly 10 clicks every 4 seconds, and the car becomes sluggish. The revs go up, but the car doesn't increase in acceleration at all. She runs flawlessly most of the time, but in these strange instances where this happens, it runs like crap
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
OK
Not trying to sound like a broken record or be difficult, but have you checked for the wires for sparking. This would be the first step. One or even two plug wires probably would not cause the problem. But if the coil wire is grounding out by the water pump it most definitely can. It is very close quarters to metal.
I only dwell on this because I have had the coil wire go bad on me and had a similar effect. It is not that un-common of probelm.
If the wires check out OK, then we can get into the more complex suggestions.
Not trying to sound like a broken record or be difficult, but have you checked for the wires for sparking. This would be the first step. One or even two plug wires probably would not cause the problem. But if the coil wire is grounding out by the water pump it most definitely can. It is very close quarters to metal.
I only dwell on this because I have had the coil wire go bad on me and had a similar effect. It is not that un-common of probelm.
If the wires check out OK, then we can get into the more complex suggestions.
Thread Starter
Burning Brakes
Joined: Nov 2009
Posts: 813
Likes: 0
From: Fort Worth TX
OK
Not trying to sound like a broken record or be difficult, but have you checked for the wires for sparking. This would be the first step. One or even two plug wires probably would not cause the problem. But if the coil wire is grounding out by the water pump it most definitely can. It is very close quarters to metal.
I only dwell on this because I have had the coil wire go bad on me and had a similar effect. It is not that un-common of probelm.
If the wires check out OK, then we can get into the more complex suggestions.
Not trying to sound like a broken record or be difficult, but have you checked for the wires for sparking. This would be the first step. One or even two plug wires probably would not cause the problem. But if the coil wire is grounding out by the water pump it most definitely can. It is very close quarters to metal.
I only dwell on this because I have had the coil wire go bad on me and had a similar effect. It is not that un-common of probelm.
If the wires check out OK, then we can get into the more complex suggestions.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
But I have never read or heard of the coil or ICM cause a wondering idle. Most of the time they cause a no start, sudden quitting or no start when hot and some other related symptoms. I suppose anything is possible but IMO would put it low on the list of probabilities.
A lot of ICMs are changed and a good deal of them do fix problems because a higher failure rate.
I would also say that of all the coils changed don’t fix the problem because they have a much lower rate and are usually changed on a guess (and hope).
Thread Starter
Burning Brakes
Joined: Nov 2009
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From: Fort Worth TX
Team Owner
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From: Fort Knox, KY
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So is it bad wires? Sure kinda' sounds like it. These HEI ignition cars are very sensitive to bad wiring issues.
If you open the hood, pull the hood lamp fuse, start the engine in the dark (or in a darkened garage) you'll see the electrical gremlins and creepy-crawlies arcing along your coil and plug wires.
If you open the hood, pull the hood lamp fuse, start the engine in the dark (or in a darkened garage) you'll see the electrical gremlins and creepy-crawlies arcing along your coil and plug wires.
Thread Starter
Burning Brakes
Joined: Nov 2009
Posts: 813
Likes: 0
From: Fort Worth TX
So is it bad wires? Sure kinda' sounds like it. These HEI ignition cars are very sensitive to bad wiring issues.
If you open the hood, pull the hood lamp fuse, start the engine in the dark (or in a darkened garage) you'll see the electrical gremlins and creepy-crawlies arcing along your coil and plug wires.
If you open the hood, pull the hood lamp fuse, start the engine in the dark (or in a darkened garage) you'll see the electrical gremlins and creepy-crawlies arcing along your coil and plug wires.
We could be on to something...
It ran SO poorly yesterday, thought it was going to die on me