Occassional backfire while starting impending doom?
Thread Starter
Burning Brakes
Joined: Nov 2017
Posts: 1,060
Likes: 80
From: Fort Mill, SC
Occassional backfire while starting impending doom?
2 x now I have had the car backfire on 1st crank while starting. Turn the key again (fear made me release the key when I heard the bang) and it starts fine.
Is this a characteristic or do I have a monster waiting to jump put and devour me slowly like a hawk eating a mouse?
Is this a characteristic or do I have a monster waiting to jump put and devour me slowly like a hawk eating a mouse?
Thread Starter
Burning Brakes
Joined: Nov 2017
Posts: 1,060
Likes: 80
From: Fort Mill, SC
What year?
Is the backfire in the exhaust or intake?
Is this the result after recent work, or did it develop on its own?
Does it run correctly once it has started?
Does it do it every time, most of the time, only once in awhile? (EDIT: I now see "occasional" in the header. Sorry).
If only once in awhile, is there any correlation between coolant temperature and likelihood of it to backfire?
EDIT: WAG: If a 92 or 93, I'd guess the optispark is wet.
Is the backfire in the exhaust or intake?
Is this the result after recent work, or did it develop on its own?
Does it run correctly once it has started?
Does it do it every time, most of the time, only once in awhile? (EDIT: I now see "occasional" in the header. Sorry).
If only once in awhile, is there any correlation between coolant temperature and likelihood of it to backfire?
EDIT: WAG: If a 92 or 93, I'd guess the optispark is wet.
Intake
Yes, runs fine.
Does it maybe every 5 starts? I dont drive too much.
I doubt the opti is wet. It doesnt see rain and no coolant leaks and since its a 96 it should be vented.
That being said, something is wrong it would seem.
I have been tuning the car.. (transmission only) which means lots of ignition on time without a start.. Leaky injector?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
Generally a backfire through the intake or carb...if it were older and had a carb... would indicate a valve or cam lobe problem.
Now preforming an injector balance test will let you see if you have a leaking injector and if they are all equal in what GM states in the manual.
Also...just because the opti-spark is vented does not mean that it is not susceptible to having problems.
DUB
Now preforming an injector balance test will let you see if you have a leaking injector and if they are all equal in what GM states in the manual.
Also...just because the opti-spark is vented does not mean that it is not susceptible to having problems.
DUB
Drifting
Joined: Jul 2004
Posts: 1,356
Likes: 291
From: MA
Just an FYI the opti could also have the rotor screws loose or they may have even fallen out. I lost one screw laying in the cap and the other screw was loose just barely holding the rotor on.
For my 96 this caused a miss and pinging under load.
For my 96 this caused a miss and pinging under load.
