And why only one cylinder? Most likely plug, wire, cap, in that order.
No spark at plug
Thread Starter
Advanced
Joined: Jan 2018
Posts: 92
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From: Brisbane, Australia
No spark at plug
Hi all,
I just had my mechanic replace my carburetor and install a 750 CFM Holley on my 69 427 Corvette.
After the car was started up one of the cylinders has no spark on idle.
What is the diagnosis order? So far I will focus on:
1) cap and rotor
2) spark plugs
3) leads
Anything else that should be checked that I have missed. The car seemed fine before and didn't seem to misfire at idle or under load.
Any help is appreciated.
Thankyou,
NJ
I just had my mechanic replace my carburetor and install a 750 CFM Holley on my 69 427 Corvette.
After the car was started up one of the cylinders has no spark on idle.
What is the diagnosis order? So far I will focus on:
1) cap and rotor
2) spark plugs
3) leads
Anything else that should be checked that I have missed. The car seemed fine before and didn't seem to misfire at idle or under load.
Any help is appreciated.
Thankyou,
NJ
Last edited by NJey1985; Aug 29, 2018 at 02:33 AM.
Racer
Joined: May 2018
Posts: 297
Likes: 43
reverse that order, assuming all else is working properly, replace plug, check for spark at the new plug, then that wire then the cap/rotor. odds are that will locate if faulty plug or broken plug wire which is most likely as described above.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
If you got a timing light it's easy enough to see of the spark is getting down the wire.
Could swap plugs and see if the problem follows the plug or not.
swap wires if that plug swap doesn't find it, does the problem follow the wire?
if still no spark then it might be rotor and or cap replacement time.
of course you could take the cap off and look at both, if there is an issue with only one cylinder it should be easy to see.
Could swap plugs and see if the problem follows the plug or not.
swap wires if that plug swap doesn't find it, does the problem follow the wire?
if still no spark then it might be rotor and or cap replacement time.
of course you could take the cap off and look at both, if there is an issue with only one cylinder it should be easy to see.
Melting Slicks
Joined: Dec 2009
Posts: 3,212
Likes: 639
From: Thunder Bay
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