Misfire at idle?!
05-20-2017, 05:24 PM
#11
Thread Starter
Join Date: Apr 2017
Location: Ohio
Posts: 8
I went through the same thing years ago - light intermittent miss at idle. Not present under load or elsewhere, no check engine light. And I went through all of the maintenance items you did as well, including turning off and disconnecting the EGR in case it was flowing excessively.
What finally cured it was closing the gap on the plugs. I went from the spec gap of .054" down to .046"-.048".
What finally cured it was closing the gap on the plugs. I went from the spec gap of .054" down to .046"-.048".
05-21-2017, 04:44 AM
#12
5th Gear Member
Join Date: Jul 2012
Location: ohio
Posts: 3,628
So once I got time, I tried what you suggested and closed the gap on the plugs to .048. It did not help in my case. .. I'm completely lost by this point since I've tried everything I can think of.. And it for sure makes it even more stressful since I have no check engine light.
If its a very noticeable dead miss you can pull single coil connectors off 1 by 1 untill you find a cylinder that does not change the idle at all.
If its just an audible sound in the exhaust note at idle , it could very well still have a small exhaust leak someplace. Even just a pin hole in a weld or joint is enough to create the sound. As the exhaust gasses expand the wave of pressure pulls some oxygen into the mix, if just the right conditions are met the extra 02 in the exaust can cause a little pop or sound similar to a slight miss.
Also check your coil connectors and fuel injector plugs are tight and not able to back off of the terminals. Sometimes the tabs break off and they tend to just kind of sit on there with the vibrations of the engine they can back off enough to cause a slight miss.
05-30-2017, 02:13 AM
#14
Thread Starter
Join Date: Apr 2017
Location: Ohio
Posts: 8
So do you have a dead miss at idle? As in a noticeable vibration or does it just sound like it has an intermittent miss?
If its a very noticeable dead miss you can pull single coil connectors off 1 by 1 untill you find a cylinder that does not change the idle at all.
If its just an audible sound in the exhaust note at idle , it could very well still have a small exhaust leak someplace. Even just a pin hole in a weld or joint is enough to create the sound. As the exhaust gasses expand the wave of pressure pulls some oxygen into the mix, if just the right conditions are met the extra 02 in the exaust can cause a little pop or sound similar to a slight miss.
Also check your coil connectors and fuel injector plugs are tight and not able to back off of the terminals. Sometimes the tabs break off and they tend to just kind of sit on there with the vibrations of the engine they can back off enough to cause a slight miss.
If its a very noticeable dead miss you can pull single coil connectors off 1 by 1 untill you find a cylinder that does not change the idle at all.
If its just an audible sound in the exhaust note at idle , it could very well still have a small exhaust leak someplace. Even just a pin hole in a weld or joint is enough to create the sound. As the exhaust gasses expand the wave of pressure pulls some oxygen into the mix, if just the right conditions are met the extra 02 in the exaust can cause a little pop or sound similar to a slight miss.
Also check your coil connectors and fuel injector plugs are tight and not able to back off of the terminals. Sometimes the tabs break off and they tend to just kind of sit on there with the vibrations of the engine they can back off enough to cause a slight miss.
I've checked all connections and all is fine. All new coils, I've even replaced pintle caps on the injectors, as some were cracked. Still no fix. What would be the best way to check for a tiny exhaust leak? I never hear anything hinting at a leak.
05-30-2017, 02:14 AM
#15
Thread Starter
Join Date: Apr 2017
Location: Ohio
Posts: 8
05-30-2017, 01:47 PM
#16
5th Gear Member
Join Date: Jul 2012
Location: ohio
Posts: 3,628
Sorry for the delay in answering. It's a little pop which has no rhythm to it, so it's not as though it is only on any specific cylinders.
I've checked all connections and all is fine. All new coils, I've even replaced pintle caps on the injectors, as some were cracked. Still no fix. What would be the best way to check for a tiny exhaust leak? I never hear anything hinting at a leak.
I've checked all connections and all is fine. All new coils, I've even replaced pintle caps on the injectors, as some were cracked. Still no fix. What would be the best way to check for a tiny exhaust leak? I never hear anything hinting at a leak.
Sometimes you just gotta get under there listen closely for the little pop sound and where its coming from under the car.
06-09-2017, 09:13 AM
#17
Thread Starter
Join Date: Apr 2017
Location: Ohio
Posts: 8
