Have a used beetle that keeps throwing up code 16716. Car seems to run fine. Keep errasing the code and it comes back within a few miles.
At one time I also received codes 16684,16685 and 16687 misfires.
Any suggestions appreciated.
While, it will take more troubleshooting; to figure out what is wrong, coil pack failures are common on these cars. I have replaced some knock sensors; only to have the code come back (occasionally), so, it makes one wonder if it caused by the wiring or other factors unrelated to the sensors themselves. IF the code is persistant; even when you keep cleaning the codes, I would think it would be a hard failure (requiring replacement) or electrical issue.
Can you give us more history of the car; have the coil packs or plugs been changed recently or ever? Usually, when the coil packs are failing; the check engine light will blink, engine will idle rough and miss, then the check engine light will stay on.
Purchased car used so I don't know if coil packs are original.
Car does not run rough and idles fine.
I replaced the driver side knock sensor over the weekend and have put 50 miles on car. So far no dash lights. Hope to get another 50 on today before I take it back to get inspected.
I did replace the rubber boot that connects the 3 PCV pipes. This was torn and was blowing directly on the sensor.The new coupler is made with hardened plastic.Thanks
There was a recall on the coil packs; so, you might call your local VW dealers service dept. with you VIN # and see if there are any recall, whether the coil packs were done. You might get the coil packs; replaced for free.
You might scan for codes; after awhile, see if any codes come back. What scan tool are you using?
Most likely; bad coils; since you have VCDS, you could use the misfire counting feature, while the car is running (measuring blocks). You can swap the coil positions; if the misfires, follow the new position, replace the coils. DO NOT buy generic junk coils; from your local auto parts store, get them from the dealer or VW specific suppliers online (ecs tuning, 1stvwparts, vwparts2go) etc. If the misfires; remain the same, I would look at the wiring (plugs, wiring harness, wire insulation cracked etc.; many have to replace the whole wiring harness with a new replacement kit; from your vw dealer), injectors (use the same swap technique) or check compression in the cylinder for internal problems. 9 times out of 10; its a coil pack failure; this, unfortunately is a very common issue! The later revisions of the coil packs (Bremi); seem to last longer but they still fail, some think the Hitachi versions are better and last longer. Check out ECS Tuning; here they list a number of options, different coil pack kits for the 1.8T.