Ignition problem
Race Director
Joined: Feb 2007
Posts: 15,413
Likes: 8,864
From: northern california
C2 of Year Finalist (track prepared) 2019
Jim
Very strange indeed.....I hope the solution shows up here cause I'll have learned something...
Thread Starter
Former Vendor
Joined: Mar 2011
Posts: 6,215
Likes: 152
From: spring branch Texas
Okay,
After changing every electrical component including the distributor, we have the same condition (only it is now always the left bank that does not fire---no more switching sides).
At 2500 RPM engine has steady 14" vacuum, and all cylinders firing.
At 1200 RPM, vacuum is steady 8", and only right bank firing.
If i manually apply vacuum to the main diaphragm, (at 1200 RPM) all cylinders fire.
I have two CSV's which I have tried; with 15" vacuum applied to either, one bleeds down in 15 sec., the other in 48 sec. Engine/fuel unit acts the same with either CSV installed.
It appears that the issue is vacuum, air flow, as it pertains to the operation of the mail diaphragm?
Oh, I did install new main diaphragm/gasket as insurance.
G.
210 748 4693
After changing every electrical component including the distributor, we have the same condition (only it is now always the left bank that does not fire---no more switching sides).
At 2500 RPM engine has steady 14" vacuum, and all cylinders firing.
At 1200 RPM, vacuum is steady 8", and only right bank firing.
If i manually apply vacuum to the main diaphragm, (at 1200 RPM) all cylinders fire.
I have two CSV's which I have tried; with 15" vacuum applied to either, one bleeds down in 15 sec., the other in 48 sec. Engine/fuel unit acts the same with either CSV installed.
It appears that the issue is vacuum, air flow, as it pertains to the operation of the mail diaphragm?
Oh, I did install new main diaphragm/gasket as insurance.
G.
210 748 4693
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Looks like you're on the right track.
If that was a '63/later unit, I'd be checking for a weak vacuum signal coming from the air meter at idle.
I can't see where the CSV would have anything to do with your problem.
I've never messed with a unit like yours. It may be different.
If that was a '63/later unit, I'd be checking for a weak vacuum signal coming from the air meter at idle.
I can't see where the CSV would have anything to do with your problem.
I've never messed with a unit like yours. It may be different.
