When to replace Coil Packs?
Thread Starter
Instructor
Joined: Mar 2008
Posts: 112
Likes: 17
When to replace Coil Packs?
Hello all:
I'm looking for some advice. I have a 1999 FRC with 137k miles. The engine has a more aggressive cam, long tube headers & BB exhaust. Recently I've noticed that in 5th or 6th gear at cruising speed of say 70 mph, i.e. low rpm that i get some pinging when I give it a little bit more throttle. I'm using BP 93 octane fuel. I installed new NGK TR5 plugs gapped at .039" about 1500 miles ago and have relatively new Taylor 10.7mm racing plug wires (I will say that the Taylor 10.7 wires cause radio interference and so just ordered a set of GM red 8mm wires so that hopefully that will get rid of the radio interference). I pulled a couple of plugs to look at them and they still look like new... nice white insulator.
This was not something that I ever had occur before and am wondering if it might be time to replace the original coil packs. Do coil packs degrade over time and need to be replaced?
Also, I've heard that the TR5IX Iridium plugs can improve performance slightly. Would you recommend them vs the standard V Groove TR5 copper plugs?
Any suggestions for what might be causing the pinging issue would be appreciated. Thanks
I'm looking for some advice. I have a 1999 FRC with 137k miles. The engine has a more aggressive cam, long tube headers & BB exhaust. Recently I've noticed that in 5th or 6th gear at cruising speed of say 70 mph, i.e. low rpm that i get some pinging when I give it a little bit more throttle. I'm using BP 93 octane fuel. I installed new NGK TR5 plugs gapped at .039" about 1500 miles ago and have relatively new Taylor 10.7mm racing plug wires (I will say that the Taylor 10.7 wires cause radio interference and so just ordered a set of GM red 8mm wires so that hopefully that will get rid of the radio interference). I pulled a couple of plugs to look at them and they still look like new... nice white insulator.
This was not something that I ever had occur before and am wondering if it might be time to replace the original coil packs. Do coil packs degrade over time and need to be replaced?
Also, I've heard that the TR5IX Iridium plugs can improve performance slightly. Would you recommend them vs the standard V Groove TR5 copper plugs?
Any suggestions for what might be causing the pinging issue would be appreciated. Thanks
Melting Slicks
Joined: Sep 2021
Posts: 2,555
Likes: 1,213
I would try various brands of gas. Even different stations near me that carry the same brand give different pinging results. My suspicion is some of them are not pumping 93 octane gas but I don't know of any test I can perform to find that out for sure.
Tech Contributor
Joined: Jan 2007
Posts: 19,398
Likes: 1,139
From: Dyer, IN
Hello all:
I'm looking for some advice. I have a 1999 FRC with 137k miles. The engine has a more aggressive cam, long tube headers & BB exhaust. Recently I've noticed that in 5th or 6th gear at cruising speed of say 70 mph, i.e. low rpm that i get some pinging when I give it a little bit more throttle. I'm using BP 93 octane fuel. I installed new NGK TR5 plugs gapped at .039" about 1500 miles ago and have relatively new Taylor 10.7mm racing plug wires (I will say that the Taylor 10.7 wires cause radio interference and so just ordered a set of GM red 8mm wires so that hopefully that will get rid of the radio interference). I pulled a couple of plugs to look at them and they still look like new... nice white insulator.
This was not something that I ever had occur before and am wondering if it might be time to replace the original coil packs. Do coil packs degrade over time and need to be replaced?
Also, I've heard that the TR5IX Iridium plugs can improve performance slightly. Would you recommend them vs the standard V Groove TR5 copper plugs?
Any suggestions for what might be causing the pinging issue would be appreciated. Thanks
I'm looking for some advice. I have a 1999 FRC with 137k miles. The engine has a more aggressive cam, long tube headers & BB exhaust. Recently I've noticed that in 5th or 6th gear at cruising speed of say 70 mph, i.e. low rpm that i get some pinging when I give it a little bit more throttle. I'm using BP 93 octane fuel. I installed new NGK TR5 plugs gapped at .039" about 1500 miles ago and have relatively new Taylor 10.7mm racing plug wires (I will say that the Taylor 10.7 wires cause radio interference and so just ordered a set of GM red 8mm wires so that hopefully that will get rid of the radio interference). I pulled a couple of plugs to look at them and they still look like new... nice white insulator.
This was not something that I ever had occur before and am wondering if it might be time to replace the original coil packs. Do coil packs degrade over time and need to be replaced?
Also, I've heard that the TR5IX Iridium plugs can improve performance slightly. Would you recommend them vs the standard V Groove TR5 copper plugs?
Any suggestions for what might be causing the pinging issue would be appreciated. Thanks
Any H or C codes ?
Thread Starter
Instructor
Joined: Mar 2008
Posts: 112
Likes: 17
Hello all:
Thanks for the feedback. Re the gas octane, I've tried both 92 octane (Costco) and the BP 93. We get pretty good fuel here in Minneapolis and I've never had a problem with either in the past... except I can say that my 2000 Jaguar XJR did not like the 92 Costco... switching to the 93 BP cured that issue immediately so I'm pretty confident in my local BP station.
Re tuning, I bought the car with the most of the mods. I did have upgraded rockers (Trunion bearing kit) and a new TPIS cam put in a few years ago but it always ran fine since then. This is an issue that just appeared recently.
I didn't think the coils were a maintenance item since they're a solid state electronic component.
I'll run a check of the codes to see what comes up.
Thanks for the feedback. Re the gas octane, I've tried both 92 octane (Costco) and the BP 93. We get pretty good fuel here in Minneapolis and I've never had a problem with either in the past... except I can say that my 2000 Jaguar XJR did not like the 92 Costco... switching to the 93 BP cured that issue immediately so I'm pretty confident in my local BP station.
Re tuning, I bought the car with the most of the mods. I did have upgraded rockers (Trunion bearing kit) and a new TPIS cam put in a few years ago but it always ran fine since then. This is an issue that just appeared recently.
I didn't think the coils were a maintenance item since they're a solid state electronic component.
I'll run a check of the codes to see what comes up.
Instructor
Joined: Oct 2021
Posts: 184
Likes: 43
From: Raleigh
If an O2 sensor is out of calibration and causing the motor to go lean, would that contribute to pinging?
What about a vacuum leak, which might lead to a lean condition and cause pinging.
When do you observe the pinging? Full throttle at low RPM? Full throttle at high RPM? All the time while under load?
If you're not getting spark due to a bad coil, the PCM should report misfires. You would get a check engine light. This would also lead to a rich condition, not lean (at least in the cylinder that's misfiring). But there is only one O2 sensor on each bank of 4 cylinders. So if one cylinder was dead, it would dump fuel into the exhaust and the computer would respond by leaning out the other 3 working cylinders on that bank. But again, you would see a check engine light under these conditions.
Maybe your check engine light bulb is burnt out. Put a code reader on the OBD port an confirm you don't have any codes being thrown.
What about a vacuum leak, which might lead to a lean condition and cause pinging.
When do you observe the pinging? Full throttle at low RPM? Full throttle at high RPM? All the time while under load?
If you're not getting spark due to a bad coil, the PCM should report misfires. You would get a check engine light. This would also lead to a rich condition, not lean (at least in the cylinder that's misfiring). But there is only one O2 sensor on each bank of 4 cylinders. So if one cylinder was dead, it would dump fuel into the exhaust and the computer would respond by leaning out the other 3 working cylinders on that bank. But again, you would see a check engine light under these conditions.
Maybe your check engine light bulb is burnt out. Put a code reader on the OBD port an confirm you don't have any codes being thrown.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,498
Likes: 3,999
From: Cape Coral, Florida
If an O2 sensor is out of calibration and causing the motor to go lean, would that contribute to pinging?
What about a vacuum leak, which might lead to a lean condition and cause pinging.
When do you observe the pinging? Full throttle at low RPM? Full throttle at high RPM? All the time while under load?
If you're not getting spark due to a bad coil, the PCM should report misfires. You would get a check engine light. This would also lead to a rich condition, not lean (at least in the cylinder that's misfiring). But there is only one O2 sensor on each bank of 4 cylinders. So if one cylinder was dead, it would dump fuel into the exhaust and the computer would respond by leaning out the other 3 working cylinders on that bank. But again, you would see a check engine light under these conditions.
Maybe your check engine light bulb is burnt out. Put a code reader on the OBD port an confirm you don't have any codes being thrown.
What about a vacuum leak, which might lead to a lean condition and cause pinging.
When do you observe the pinging? Full throttle at low RPM? Full throttle at high RPM? All the time while under load?
If you're not getting spark due to a bad coil, the PCM should report misfires. You would get a check engine light. This would also lead to a rich condition, not lean (at least in the cylinder that's misfiring). But there is only one O2 sensor on each bank of 4 cylinders. So if one cylinder was dead, it would dump fuel into the exhaust and the computer would respond by leaning out the other 3 working cylinders on that bank. But again, you would see a check engine light under these conditions.
Maybe your check engine light bulb is burnt out. Put a code reader on the OBD port an confirm you don't have any codes being thrown.
Actually the misfiring cylinder will run LEAN and not rich as one may think !!…the unburned fuel will just occupy space within the combustion chamber and the O2 sensor detects oxygen and not this unburned fuel…video to verify !!
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Actually the misfiring cylinder will run LEAN and not rich as one may think !!…the unburned fuel will just occupy space within the combustion chamber and the O2 sensor detects oxygen and not this unburned fuel…video to verify !!
https://youtu.be/G_89r12vZFw?si=k7u6HIDm08VYalQp
https://youtu.be/G_89r12vZFw?si=k7u6HIDm08VYalQp