Charging problems and misfire.
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Charging problems and misfire.
A few days ago I changed my spark plug wires to AC Delco red wires also installed autolite copper spark plugs, before I was suspecting a slight misfire which is why I changed the plugs and wires now I'm almost certain there's a misfire because the car seems to run a lot rougher and is lacking quite a bit of power
The strange thing about the charging problem is that at idle when you start the car the gauge shows 14.4 V so it's charging is normal however as soon as you hit the throttle and get the car over 1500 rpm's the voltage drop to below 12 V which I can tell it's not charging the car I got the service charging system message on the DIC however it has not come back again
I have read that it could be spark plug wires plugs orinterfering with the alternator signal and I've also read that after hitting the Rev limiter some alternators are blown
I went to a local auto store and have them test the alternator at idle the alternator tested fine however when we gave it a little bit of gas over 1500 RPMs the man said that the test showed the voltage regulator was a bad inside of the alternator so does this sound like something that could be related to interference
The car has uncoated long tube headers they get pretty hot so if there's anything I should check for melting please let me know all of my starter wires have be shrouded and appear ok
please help!
The strange thing about the charging problem is that at idle when you start the car the gauge shows 14.4 V so it's charging is normal however as soon as you hit the throttle and get the car over 1500 rpm's the voltage drop to below 12 V which I can tell it's not charging the car I got the service charging system message on the DIC however it has not come back again
I have read that it could be spark plug wires plugs orinterfering with the alternator signal and I've also read that after hitting the Rev limiter some alternators are blown
I went to a local auto store and have them test the alternator at idle the alternator tested fine however when we gave it a little bit of gas over 1500 RPMs the man said that the test showed the voltage regulator was a bad inside of the alternator so does this sound like something that could be related to interference
The car has uncoated long tube headers they get pretty hot so if there's anything I should check for melting please let me know all of my starter wires have be shrouded and appear ok
please help!
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First off, copper spark plugs? Where did you get that info from? I thought it took an iridium tipped plug. And about the wires, are they tightly clicked on the tops of each spark plug?
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Unless you have 100K on the car, all you had to do was pull the plugs, clean then, check the gaps to make sure that they are .040", then put them back in with antiseaze grease on the plug threads. The plugs are good for 100K, and really need to remove the replacement plugs since they are the wrong type for the car.
Also to point out, do not remove or install the spark plugs until the motor/heads at room temperature and the plugs only get torqued to 11ftbs. Removing or installing the plugs to a hot engine will end up with your stripping the spark plug channel threads out of the heads.
Now on the wires, since they can be a pain to remove, once you have them off for the first time, put a multimeter to them to make sure that you have not killed one of the ends?the wires still have a continuity through them. When they check out, tweak the metal ends on the coil side so it will get a good bite to the inside of the coil, break out some dielectric grease and a Q tip and put a light coat of grease on the inside of the boots and electrical ends in the wired. When putting the wires back on, make sure that you can feel both ends snap into place. Hence without the dielectric grease on the inside of the rubber boots, very possible to not get the plugs correctly snapped into place.
While you have the fuel rail covers off, also a good time to check the connectors to coils as well. Since you are having mis-fires, pop each coil connector, hit both the connector and coil sockets with electrical contact cleaner (comes in a spray can), dab some dielectric grease on the contacts and reset the connectors to the coils.
As for your charging problem, one of your brushes is either about worn out, or dust bound to the brush carrier in the alternator and loosing contact to the armature as the alternator spins faster.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
Also to point out, do not remove or install the spark plugs until the motor/heads at room temperature and the plugs only get torqued to 11ftbs. Removing or installing the plugs to a hot engine will end up with your stripping the spark plug channel threads out of the heads.
Now on the wires, since they can be a pain to remove, once you have them off for the first time, put a multimeter to them to make sure that you have not killed one of the ends?the wires still have a continuity through them. When they check out, tweak the metal ends on the coil side so it will get a good bite to the inside of the coil, break out some dielectric grease and a Q tip and put a light coat of grease on the inside of the boots and electrical ends in the wired. When putting the wires back on, make sure that you can feel both ends snap into place. Hence without the dielectric grease on the inside of the rubber boots, very possible to not get the plugs correctly snapped into place.
While you have the fuel rail covers off, also a good time to check the connectors to coils as well. Since you are having mis-fires, pop each coil connector, hit both the connector and coil sockets with electrical contact cleaner (comes in a spray can), dab some dielectric grease on the contacts and reset the connectors to the coils.
As for your charging problem, one of your brushes is either about worn out, or dust bound to the brush carrier in the alternator and loosing contact to the armature as the alternator spins faster.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
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Unless you have 100K on the car, all you had to do was pull the plugs, clean then, check the gaps to make sure that they are .040", then put them back in with antiseaze grease on the plug threads. The plugs are good for 100K, and really need to remove the replacement plugs since they are the wrong type for the car.
Also to point out, do not remove or install the spark plugs until the motor/heads at room temperature and the plugs only get torqued to 11ftbs. Removing or installing the plugs to a hot engine will end up with your stripping the spark plug channel threads out of the heads.
Now on the wires, since they can be a pain to remove, once you have them off for the first time, put a multimeter to them to make sure that you have not killed one of the ends?the wires still have a continuity through them. When they check out, tweak the metal ends on the coil side so it will get a good bite to the inside of the coil, break out some dielectric grease and a Q tip and put a light coat of grease on the inside of the boots and electrical ends in the wired. When putting the wires back on, make sure that you can feel both ends snap into place. Hence without the dielectric grease on the inside of the rubber boots, very possible to not get the plugs correctly snapped into place.
While you have the fuel rail covers off, also a good time to check the connectors to coils as well. Since you are having mis-fires, pop each coil connector, hit both the connector and coil sockets with electrical contact cleaner (comes in a spray can), dab some dielectric grease on the contacts and reset the connectors to the coils.
As for your charging problem, one of your brushes is either about worn out, or dust bound to the brush carrier in the alternator and loosing contact to the armature as the alternator spins faster.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
Also to point out, do not remove or install the spark plugs until the motor/heads at room temperature and the plugs only get torqued to 11ftbs. Removing or installing the plugs to a hot engine will end up with your stripping the spark plug channel threads out of the heads.
Now on the wires, since they can be a pain to remove, once you have them off for the first time, put a multimeter to them to make sure that you have not killed one of the ends?the wires still have a continuity through them. When they check out, tweak the metal ends on the coil side so it will get a good bite to the inside of the coil, break out some dielectric grease and a Q tip and put a light coat of grease on the inside of the boots and electrical ends in the wired. When putting the wires back on, make sure that you can feel both ends snap into place. Hence without the dielectric grease on the inside of the rubber boots, very possible to not get the plugs correctly snapped into place.
While you have the fuel rail covers off, also a good time to check the connectors to coils as well. Since you are having mis-fires, pop each coil connector, hit both the connector and coil sockets with electrical contact cleaner (comes in a spray can), dab some dielectric grease on the contacts and reset the connectors to the coils.
As for your charging problem, one of your brushes is either about worn out, or dust bound to the brush carrier in the alternator and loosing contact to the armature as the alternator spins faster.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
Oreillys told me they didn't have the iridiums anyways I kept the original plugs when I was chasing down a strange misfire. Problem isthe misfire is still there and I'm suspecting a broken (dual spring style) valve spring or bent pushrod. I will replace the plugs back. And hope and pray the springs are the problem
Last edited by That_White_C6; Mar 10, 2015 at 12:33 AM.
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Sent you are link on changing the brushes, so that should have you covered there.
Also, with uncoated headers, get a heat shield over the starter solenoid.
The backlite plastic on the end of the solenoid (where the cables bolt up) is not going to last long with the heat off the headers.
https://www.corvetteforum.com/forums...headers-2.html
Also, with uncoated headers, get a heat shield over the starter solenoid.
The backlite plastic on the end of the solenoid (where the cables bolt up) is not going to last long with the heat off the headers.
https://www.corvetteforum.com/forums...headers-2.html
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From: Hudson WI
NCM Sinkhole Donor
Wow excellent post Can you give me info about rebuilding the alternator and where you find one for $100? Reman local is $170 thanks!
Oreillys told me they didn't have the iridiums anyways I kept the original plugs when I was chasing down a strange misfire. Problem isthe misfire is still there and I'm suspecting a broken (dual spring style) valve spring or bent pushrod. I will replace the plugs back. And hope and pray the springs are the problem
Oreillys told me they didn't have the iridiums anyways I kept the original plugs when I was chasing down a strange misfire. Problem isthe misfire is still there and I'm suspecting a broken (dual spring style) valve spring or bent pushrod. I will replace the plugs back. And hope and pray the springs are the problem
Last edited by timd38; Mar 10, 2015 at 02:28 PM.
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NCM Sinkhole Donor
http://www.harborfreight.com/non-con...ing-61894.html
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OBDII scanner will pull the code for a misfire and tell you what cylinder is having the problem.
From there, pull the coil from that cylinder and the one next to it, swap the coil locations and see if the misfire moves to the new location as the coil was moved to.
If no misfires, the problem was solved when you moved the coils (connector problems).
If the misfire stays at the same cylinder with the other coil in that position, then you know that the problem is with the wiring before the coil.
If the misfire moved to the new cylinder, then the coil is bad instead.
From there, pull the coil from that cylinder and the one next to it, swap the coil locations and see if the misfire moves to the new location as the coil was moved to.
If no misfires, the problem was solved when you moved the coils (connector problems).
If the misfire stays at the same cylinder with the other coil in that position, then you know that the problem is with the wiring before the coil.
If the misfire moved to the new cylinder, then the coil is bad instead.
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Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
OBDII scanner will pull the code for a misfire and tell you what cylinder is having the problem.
From there, pull the coil from that cylinder and the one next to it, swap the coil locations and see if the misfire moves to the new location as the coil was moved to.
If no misfires, the problem was solved when you moved the coils (connector problems).
If the misfire stays at the same cylinder with the other coil in that position, then you know that the problem is with the wiring before the coil.
If the misfire moved to the new cylinder, then the coil is bad instead.
From there, pull the coil from that cylinder and the one next to it, swap the coil locations and see if the misfire moves to the new location as the coil was moved to.
If no misfires, the problem was solved when you moved the coils (connector problems).
If the misfire stays at the same cylinder with the other coil in that position, then you know that the problem is with the wiring before the coil.
If the misfire moved to the new cylinder, then the coil is bad instead.
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From: katy tx
As for your charging problem, one of your brushes is either about worn out, or dust bound to the brush carrier in the alternator and loosing contact to the armature as the alternator spins faster.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
The fix is around $4, or you can replace the alternator instead for around a C note.
Note here, check your battery cable where they come down the back passenger side rear of the engine. The cables can rub against the back of the motor to wear off the cable shield and cause a short against the aluminum engine block. If you find this, then use a Zip tie to pull the cable off from against engine to hold it to a cable off the motor instead.
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I talking about something like Elm Scan 5 or ScanMaster-Elm to check the mis-fire counts (Mode $06 data) for the last 10 run cycles instead, since this will list which cylinder(s) had any misfires to begin with (below the threshold to trigger a DIC fault code).
Last edited by Dano523; Mar 11, 2015 at 08:29 PM.
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Your thinking code reader where when problem is so bad/the misfire count get high enough, that the DIC will light up with a problem code.
I talking about something like Elm Scan 5 or ScanMaster-Elm to check the mis-fire counts (Mode $06 data) for the last 10 run cycles instead, since this will list which cylinder(s) had any misfires to begin with (below the threshold to trigger a DIC fault code).
I talking about something like Elm Scan 5 or ScanMaster-Elm to check the mis-fire counts (Mode $06 data) for the last 10 run cycles instead, since this will list which cylinder(s) had any misfires to begin with (below the threshold to trigger a DIC fault code).
http://m.harborfreight.com/can-obd-i...0693-9479.html