Lars, engine miss help.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 203
From: Loveland, CO
Lars, engine miss help.
Lars, I took the '69 out for a drive on Sunday and it didn't seem to run right. Came home and investigated cause of miss. Used infrared temp. gun on exhaust ports to identify problem cylinder. No. 5 was cooler than the rest and seemed to be the culprit.
See photo below. Could this be my problem?
Your neighbor, Ralph
PS: can I have my "Tuned by Lars" sticker now?
See photo below. Could this be my problem?
Your neighbor, Ralph
PS: can I have my "Tuned by Lars" sticker now?
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Ralph -
Be careful about jumping to rash conclusions: Automotive engine troubleshooting is a science best left to trained automotive technicians, and it's not something you should be doing yourself. I would first recommend you take your Vette to a real mechanic who is professionally trained to work on fine cars, such as the Corvette.
That being said, a Corvette has 8 cylinders for a reason: We all know that cars only need 6 or 4 cylinders for a perfectly satisfactory level of performance. A Corvette has 8 so that you have 2 spares. If one drops off, there is no need to be alarmed or to take any action: You still have at least one more than you really need. The spare cylinders are like lifeboats on a ship: You don't really need them or use them unless there is a need, and your lifeboat cylinder has now been used. Just leave it.
If you really feel a need to get the cylinder running again, there is really no need to go to the trouble of repairing or replacing that plug wire. All you need is more voltage to make the spark jump the gap to the plug. Install a very large aftermarket coil along with an expensive Capacitive Discharge system. This will bump your secondary voltage up from 18,000 to at least 40,000, and will be adequate to overcome any minor wiring problems such as you have shown.
Finally, if you really need to fix something, I'd suggest you blame the carburetor: The carb is ALWAYS the source of any engine miss, and is the culprit in all drivability and performance issues. Replace the carb. In your case, replace all 3 of them.
Lars
Be careful about jumping to rash conclusions: Automotive engine troubleshooting is a science best left to trained automotive technicians, and it's not something you should be doing yourself. I would first recommend you take your Vette to a real mechanic who is professionally trained to work on fine cars, such as the Corvette.
That being said, a Corvette has 8 cylinders for a reason: We all know that cars only need 6 or 4 cylinders for a perfectly satisfactory level of performance. A Corvette has 8 so that you have 2 spares. If one drops off, there is no need to be alarmed or to take any action: You still have at least one more than you really need. The spare cylinders are like lifeboats on a ship: You don't really need them or use them unless there is a need, and your lifeboat cylinder has now been used. Just leave it.
If you really feel a need to get the cylinder running again, there is really no need to go to the trouble of repairing or replacing that plug wire. All you need is more voltage to make the spark jump the gap to the plug. Install a very large aftermarket coil along with an expensive Capacitive Discharge system. This will bump your secondary voltage up from 18,000 to at least 40,000, and will be adequate to overcome any minor wiring problems such as you have shown.
Finally, if you really need to fix something, I'd suggest you blame the carburetor: The carb is ALWAYS the source of any engine miss, and is the culprit in all drivability and performance issues. Replace the carb. In your case, replace all 3 of them.
Lars
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Ralph -
Be careful about jumping to rash conclusions: Automotive engine troubleshooting is a science best left to trained automotive technicians, and it's not something you should be doing yourself. I would first recommend you take your Vette to a real mechanic who is professionally trained to work on fine cars, such as the Corvette.
That being said, a Corvette has 8 cylinders for a reason: We all know that cars only need 6 or 4 cylinders for a perfectly satisfactory level of performance. A Corvette has 8 so that you have 2 spares. If one drops off, there is no need to be alarmed or to take any action: You still have at least one more than you really need. The spare cylinders are like lifeboats on a ship: You don't really need them or use them unless there is a need, and your lifeboat cylinder has now been used. Just leave it.
If you really feel a need to get the cylinder running again, there is really no need to go to the trouble of repairing or replacing that plug wire. All you need is more voltage to make the spark jump the gap to the plug. Install a very large aftermarket coil along with an expensive Capacitive Discharge system. This will bump your secondary voltage up from 18,000 to at least 40,000, and will be adequate to overcome any minor wiring problems such as you have shown.
Finally, if you really need to fix something, I'd suggest you blame the carburetor: The carb is ALWAYS the source of any engine miss, and is the culprit in all drivability and performance issues. Replace the carb. In your case, replace all 3 of them.
Lars
Be careful about jumping to rash conclusions: Automotive engine troubleshooting is a science best left to trained automotive technicians, and it's not something you should be doing yourself. I would first recommend you take your Vette to a real mechanic who is professionally trained to work on fine cars, such as the Corvette.
That being said, a Corvette has 8 cylinders for a reason: We all know that cars only need 6 or 4 cylinders for a perfectly satisfactory level of performance. A Corvette has 8 so that you have 2 spares. If one drops off, there is no need to be alarmed or to take any action: You still have at least one more than you really need. The spare cylinders are like lifeboats on a ship: You don't really need them or use them unless there is a need, and your lifeboat cylinder has now been used. Just leave it.
If you really feel a need to get the cylinder running again, there is really no need to go to the trouble of repairing or replacing that plug wire. All you need is more voltage to make the spark jump the gap to the plug. Install a very large aftermarket coil along with an expensive Capacitive Discharge system. This will bump your secondary voltage up from 18,000 to at least 40,000, and will be adequate to overcome any minor wiring problems such as you have shown.
Finally, if you really need to fix something, I'd suggest you blame the carburetor: The carb is ALWAYS the source of any engine miss, and is the culprit in all drivability and performance issues. Replace the carb. In your case, replace all 3 of them.
Lars
