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Chrisw023
01-22-2018, 12:08 AM
So car has always run fine pulled it in the garage and changed coil packs and checked the spark splugs and everything seemed fine. Go to start the car and get what sounds like the starter not turning or something. Video is not mine but cars making the same exact sound if anyone has any ideas? Planning to look at it more tomorrow after work and pull codes. Car's a manual 1.8t


https://www.youtube.com/watch?v=20Fx7JZqd6Y

walky_talky20
01-22-2018, 05:23 AM
That car sounded fine. That is the sound of the starter cranking the engine (ie: rotating the engine successfully). It just didn't start. We call that a "Crank, no start".

Usually on a 1.8T the cause will be:
- Incorrect fuel mixture (ie: not enough fuel)
- Flooded or fouled plugs
- No spark/weak spark

If it were mine, I'd try the following, in this order:
- "Clear Flood Mode". Push the gas pedal to the floor and hold it, crank the starter for 5 full seconds at a time, 10 seconds rest. Repeat maybe 3 times. Then try to start as normal (don't touch pedals).
- Check for spark. Sometimes moving the coil packs around like you did, you can break the brittle wires or cause them to short out and blow the fuse. No more power to coil packs (fuse 32 blown).
- Checking for spark means unplug 1 coil (the front one is best), pop it out, plug it back into the harness, stick a screwdriver in the end and hold it by the handle 1/16" away from the valve cover. Crank starter. Observe spark.
- Alternatively you can do the same test using a spark plug instead of a screwdriver. Stick a spare spark plug in the end of the coil pack, hold the other end (the threads) against the valve cover. Crank Starter. Observe spark.

Sounds like your coil packs are new, but if they weren't, you would want to ascertain the strength of the spark. It should be strong and blue and able to jump a 1/8" gap easily. If it's weak and orange and will barely jump a 1/16" or less, the coil pack is shot.

If none of that led to any titillating discoveries, then you'll have to look into things in some more detail.

Chrisw023
01-22-2018, 10:31 PM
Thanks Walky ended up being cylinder washdown. plugs and cylinders were extremely wet with gas like you mentioned, cleaned them up and put a little oil down each cylinder and turned it a couple times with the injectors disconnected then put it all back together and it fired up with alot of smoke for a few minutes. now to change the oil.

walky_talky20
01-23-2018, 04:47 AM
Randomly flooding out does seem to be a thing on 1.8T's. Has happened to mine at least once. My only theory is either a momentary bad reading from the coolant temp sensor, or some sort of ECU software fault in the cold start routine.

I'd say if you are doing any work on the cooling system or rear coolant flange in the near future, pop in a new OEM sensor while you're there.