1.8 TFSI BZB timing chain jumped

Hello everyone,

Yesterday, I had a 1.8 TFSI from a friend in my circle. Very nice A3 S Line Cabrio, first owner, with only 118,000 km.

It didn't start when I tried to turn it on. While troubleshooting, I initially groped around in the dark because there were no error messages logged.

Upon closer inspection of the engine, it was evident that the ignition system and fuel pump were seized, and the camshaft was misaligned by 8° from the maximum tolerance value. "I removed the cover, and it quickly became clear that it had jumped two teeth."

Okay, here are the two questions:

1.) If the message server (MSG) detects this, why doesn't it throw an error? Is that really possible?

2.) Is the engine salvageable? So, are 2 valves sufficient for a valve-piston collision in the engine?

Best regards,

Bo.

Hi,

Quote:

It didn't start when I tried to turn it on.

Does that mean it was running perfectly normally until I stopped the engine? Were there any rattling noises beforehand?
If the timing chain was so severely stretched that it jumped teeth even during startup, there might not be any error codes recorded.

Quote:

Can the engine still be saved? Okay, so, are 2 teeth enough for a valve and piston collision in that engine?

It's hard to say, can it still be turned by hand?

I would like to check the valve timing the old-fashioned way!

Best regards, Richard.

Hello Richard,

E30_V8 wrote:

That means it was running perfectly fine until the engine was turned off? No rattling noises beforehand?

Okay. No abnormalities. Also, no unusual mechanical noises when attempting to start it. Because the starter motor was making a "strange noise," the owner didn't try to start it again and called me.

E30_V8 wrote:

It's hard to say, but can it still be turned manually?

When I got there, I first tried rocking the bike back and forth in second gear to see if the engine was turning over. Once I confirmed that the chain wasn't broken, I tried to start it. The starter motor is spinning too easily, there's no compression, but also no knocking or rattling sounds.

Quote:

I would like to check the valve timing the old-fashioned way!

On Saturday, I'll do that, and we'll perform an endoscopy. Then we'll decide whether or not to remove the head.

Thank you.

Bo.

There were 5 teeth. Engine is scrap!

Hello,

Was if the engine happened to be facing downhill, and the reverse gear was engaged?
I've experienced this exact issue twice before, and each time it was accompanied by the situation described above.
Unfortunately, the motor absolutely cannot rotate in reverse, and the chain immediately jumps when you try.

Best regards,

klahaui wrote:

Hello, Was if the engine happened to be facing downhill, and the reverse gear was engaged? I've experienced this exact issue twice before, and each time it was accompanied by the situation described above. Unfortunately, the motor absolutely cannot rotate in reverse, and the chain immediately jumps when you try. Best regards

The parking garage floor was perfectly level.

You don't have to understand it. According to the mechanic, this seems to be a fairly common issue with this type of engine.

Regards,

Bo.