How important is a strong ignition spark for FE

[Cd]

My '93 Civic fires right up every single time - sometimes the instant i turn the key.
Most of the time i don't even hear the starter.
However, the car has always had a very weak spark in several ( if not all ) cylinders .
Power seems weak, but this is an old car with a lot of miles. The car I'd also an automatic.
the distributor is new, the wires and plugs as well.

Will i see a big FE Improvement by fixing the issue ?

[pgfpro]

Originally Posted by Cd

My '93 Civic fires right up every single time - sometimes the instant i turn the key.
Most of the time i don't even hear the starter.
However, the car has always had a very weak spark in several ( if not all ) cylinders .
Power seems weak, but this is an old car with a lot of miles. The car I'd also an automatic.
the distributor is new, the wires and plugs as well.

Will i see a big FE Improvement by fixing the issue ?

What is the condition of the ground wire on the cylinder head. You can a simple test by taking some jumper cables and making four extra temporary grounds then recheck spark.

[Cd]

The ground wire is in great shape, and I even added another ( very small ) ground wire.
Old Mech had suggested looking at the grounds some time ago as well.

What puzzles me is that the car fires right up. If there was a grounding problem, or a problem with the distributor, wouldn't there be some problems starting the car ?

[Daox]

How do you know it has a weak spark?

[Cd]

Originally Posted by Daox

How do you know it has a weak spark?

Well it felt pretty weak when i touched it.


....
....what

( Not being a jerk, just my lame attempt at humor )


I tested the spark plugs and when the car is cranked, there is a pale orange spark. Quite weak.
Ideally, it should be a bright blue.

Commercials for Splitfire type plugs would have you believe that some of your fuel is wasted if you have poor spark.
Is there any truth to that ?

If the fuel ignites, then it is on fire...no matter if the spark was weak or not.... right ?

[UFO]

That's what I'd think, unless it was weak enough to cause an occasional misfire.

[ksa8907]

Originally Posted by Cd

Well it felt pretty weak when i touched it.


....
....what

( Not being a jerk, just my lame attempt at humor )


I tested the spark plugs and when the car is cranked, there is a pale orange spark. Quite weak.
Ideally, it should be a bright blue.

Commercials for Splitfire type plugs would have you believe that some of your fuel is wasted if you have poor spark.
Is there any truth to that ?

If the fuel ignites, then it is on fire...no matter if the spark was weak or not.... right ?

What is the gap set to? You mentioned that you have good grounds but what about a good supply voltage?

[markweatherill]

Originally Posted by Cd

when the car is cranked, there is a pale orange spark. Quite weak.
Ideally, it should be a bright blue.

Try it with the engine running. You may see a difference!

[Cd]

Originally Posted by ksa8907

What is the gap set to? You mentioned that you have good grounds but what about a good supply voltage?

Gap is set to factory specs. Supply voltage ....hmmm...well I need to test that.
The distributor ( which has a coil built in ) / plugs and wires are all new.

I'll recheck the grounds again this weekend. I just looked it up, and there are a lot more than I thought :

[Cd]

Originally Posted by markweatherill

Try it with the engine running. You may see a difference!

How do you do that ?