Suddenly car is shaking and blinking check engine light
#11
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It was a defective spark plug it looks like
Moved it from CYL-1 to CYL-2, misfiring moved to CYL-2. Plug is only 4 months old. Wire resistance was 5.5 k-ohms, within spec.
#13
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The replacement spark plug bought from Audi/VW does the same thing!
It is all just happening on CYL-2 now!
Argh! Should have known better than to think an OEM part will work better! I'm going to try getting another spark plug tomorrow at a local auto parts store.
There is no way to check the gap on these plugs either, because they have 2 electrodes.
Argh! Should have known better than to think an OEM part will work better! I'm going to try getting another spark plug tomorrow at a local auto parts store.
There is no way to check the gap on these plugs either, because they have 2 electrodes.
#14
Hows the symptoms now? ....
Spark plugs, being fairly simple devices, are not often subject to malfunctions when new. It's possible of course, but the odds are extremely unlikely. Is there anything else that could be involved coincidently?
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Not sure what it is about these plugs...
My plugs are Denso but I put an Audi dealer plug into CYL-2. Same thing happens (always CYL-2 now). I have a new Denso and that will be the third plug. After that, I'm just going to have to forget about this oddity.
There is no good way to check the gap on these two terminal spark plugs. However, is there something else special that might have been done to the other plugs so that they don't display this problem? (repeatedly misfiring when revving at 2000 RPM in PARK/NEUTRAL only) We know it is not the CYL itself because this was CYL-1 until I swapped CYL-1 and CYL-2 plugs.
There is no good way to check the gap on these two terminal spark plugs. However, is there something else special that might have been done to the other plugs so that they don't display this problem? (repeatedly misfiring when revving at 2000 RPM in PARK/NEUTRAL only) We know it is not the CYL itself because this was CYL-1 until I swapped CYL-1 and CYL-2 plugs.
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Replaced that spark plug tonight, now it moves to CYL-6
Though not as bad and more distributed. I also used dielectric grease on the spark plug boot head (not the threads!) when installing the new plug.
Seems like the system is picking out the "weakest" plug among the group to misfire on. As I improve the plugs, it just picks another one. I'm going to add dielectric grease to the spark boot on CYL-6 now and see if it moves again; then I know it is just a spark plug contacts issue.
Seems like the system is picking out the "weakest" plug among the group to misfire on. As I improve the plugs, it just picks another one. I'm going to add dielectric grease to the spark boot on CYL-6 now and see if it moves again; then I know it is just a spark plug contacts issue.
#18
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The replacement coil also has failed already
Very frustrating when even new parts apparently aren't good out of the box.
I had to prove the coil was the cause of the misfires this time with an inline spark indicator.
I had to prove the coil was the cause of the misfires this time with an inline spark indicator.
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