CoffeeAndJam
Registered User
Hey all,
Sorry for a bit of a long post. Want to give as much info as possible.
I’m having random cold start misfires in my 2017 S3 that’s setting off the CEL. It has 30k miles on it. Stock except for tinted windows. This issue has been going on for over two months between the dealer and I. They haven’t been able to find the cause (they thought they did).
It started with me changing all the coils and plugs myself and inspecting the PCV valve after my first CEL was thrown for random misfires on multiple cylinders (also got misfire codes for cylinder 3&4). PCV valve was good. Changing coils and plugs didn’t solve the problem.
I brought it to the dealer next. They’ve done compression tests, leakdown tests, checked the camshaft adjuster (exhaust side), ran a fuel additive through it, change plugs again (said that was the problem at first along with bad fuel), and did a software update to fix the cold start issues (apparently there’s an update just for that). All the tests came back great, no leakage and compression is 180psi on all cylinders.
After all that testing (see attached service report) they said the next step was to replace the injectors for $1300 (my car is TD1, long story). They said they’re possibly causing fuel to leak into the cylinders over time when sitting, causing misfires during start. So I OK’ed the repair. Got the car today, and the car is experiencing the same problems as before (coldstart misfires) and it’s a matter of time before the CEL comes back on.
Needless to say, I’m very frustrated and don’t want to blindly throw money at it anymore. Anyone have suggestions? Someone told me to have them pull the valve cover and check the springs, since a VW tech sees a number of cars come through for bad springs.
Sorry for a bit of a long post. Want to give as much info as possible.
I’m having random cold start misfires in my 2017 S3 that’s setting off the CEL. It has 30k miles on it. Stock except for tinted windows. This issue has been going on for over two months between the dealer and I. They haven’t been able to find the cause (they thought they did).
It started with me changing all the coils and plugs myself and inspecting the PCV valve after my first CEL was thrown for random misfires on multiple cylinders (also got misfire codes for cylinder 3&4). PCV valve was good. Changing coils and plugs didn’t solve the problem.
I brought it to the dealer next. They’ve done compression tests, leakdown tests, checked the camshaft adjuster (exhaust side), ran a fuel additive through it, change plugs again (said that was the problem at first along with bad fuel), and did a software update to fix the cold start issues (apparently there’s an update just for that). All the tests came back great, no leakage and compression is 180psi on all cylinders.
After all that testing (see attached service report) they said the next step was to replace the injectors for $1300 (my car is TD1, long story). They said they’re possibly causing fuel to leak into the cylinders over time when sitting, causing misfires during start. So I OK’ed the repair. Got the car today, and the car is experiencing the same problems as before (coldstart misfires) and it’s a matter of time before the CEL comes back on.
Needless to say, I’m very frustrated and don’t want to blindly throw money at it anymore. Anyone have suggestions? Someone told me to have them pull the valve cover and check the springs, since a VW tech sees a number of cars come through for bad springs.