Distributor Cap - Cause or Symptom - Misfire ?
Thread Starter
Intermediate
Joined: Apr 2007
Posts: 31
Likes: 0
From: Farmington Hills MI
Distributor Cap - Cause or Symptom - Misfire ?
I have had my 85 for about 2 months now and have made some major improvements. I always noticed a slight hesitation, that I thought was a misfire. The car ran OK, and I thought it was normal for its age.
It pointed to the electrical system and I bought a new ignition coil. When I was in there, I noticed my distributor cap, one of the terminals was corroded. I changed this with the ignition coil, and my car runs MUCH better. In fact I am getting 26.5 MPG on the freeway, almost 3.5 MPG better than I have ever had with it before.
My question is , was this the cause of my problems, or a symptom, and how can I confirm that?
Thanks for everyone who posts useful info on this site, its a lifesaver!
It pointed to the electrical system and I bought a new ignition coil. When I was in there, I noticed my distributor cap, one of the terminals was corroded. I changed this with the ignition coil, and my car runs MUCH better. In fact I am getting 26.5 MPG on the freeway, almost 3.5 MPG better than I have ever had with it before.
My question is , was this the cause of my problems, or a symptom, and how can I confirm that?
Thanks for everyone who posts useful info on this site, its a lifesaver!
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Even though you are getting better gas mileage,I would consider changing the plug wires as well.
If you have that much corrosion on the cap, I'm sure the wire connection is just as corroded.
It might be just a short time before you have the same problem again if you don't change them.
At least the one wire anyway.
If you have that much corrosion on the cap, I'm sure the wire connection is just as corroded.
It might be just a short time before you have the same problem again if you don't change them.
At least the one wire anyway.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Perhaps. Put it back together the way it was. Then if you have a timing light, connect it to that wire and just point the timing gun to your palm and note the flashes. You'll be able to "see" what's going on. If it does not look the same as the rest of the wires, buy a new cap. Change the rotor while you're in there. Remember, for the coil, the plunger goes in the hole first, then the round rubber peice on top of that.
Last edited by 86PACER; Jul 18, 2007 at 04:40 PM.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
You're right. I read too fast. Then it should be obvious. If the car improved and smoothed out after he changed that, then yes that must have been what was wrong. Ignition coils usually just either work or die all together, so it's more likely the cap was what fixed it.
If he wants to "confirm" then just put the old coil back in and start it. If no change, then it was the old cap that must have been bad.
If he wants to "confirm" then just put the old coil back in and start it. If no change, then it was the old cap that must have been bad.
Last edited by 86PACER; Jul 18, 2007 at 04:46 PM.
Thread Starter
Intermediate
Joined: Apr 2007
Posts: 31
Likes: 0
From: Farmington Hills MI
If he wants to "confirm" then just put the old coil back in and start it. If no change, then it was the old cap that must have been bad.
I forgot to mention that some of the paperwork I have on the car says that the cap was changed about a year ago...Is this going to keep happening?
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
What does the bottom inside of that wire look like? You never said if you changed the wires or not. If it looks fine, just forget about it.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
7 Bolt-On Upgrades From Extreme Online Store to Level Up Your C6 Corvette
Pouria Savadkouei
Thread Starter
Intermediate
Joined: Apr 2007
Posts: 31
Likes: 0
From: Farmington Hills MI
Safety Car
Joined: Nov 2004
Posts: 4,991
Likes: 5
From: The Pines South Jersey
My question was more on the lines of...will the corrosion come back? Could there be an underlying electrical problem causing that much corrosion, or perhaps just a loose wire?
I forgot to mention that some of the paperwork I have on the car says that the cap was changed about a year ago...Is this going to keep happening?
I forgot to mention that some of the paperwork I have on the car says that the cap was changed about a year ago...Is this going to keep happening?
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
