Hello,
I have a 2003 A4 1.8t.

I changed my head gasket and in the process I broke one of the bolts that hold the exhaust manifold to the back of the turbo. (not sure what its called) Only 2 of the bolts are attached there. Do you thing thats what's causing my car to start misfiring after accelerating above 2500rpm? or do you think there is a bigger issue here?


Thanks

 

Is the broken bolt stuck in the block or is it just a matter of getting a replacement bolt to secure the exhaust manifold?

I would start with the obvious and get all the bolts properly installed first before looking at anything else that could cause misfiring.

Just my 2cents

 

Yea only the head of the bolt broke off and the other half is still stuck so I cannot put a new bolt in there. I would get a new bolt in there if I could. I'm thinking about drilling out the other bolt but I am risking screwing up the thread.
Also, the ignition coils have not been changed for 60k miles now. Do you think I should change them? They are not the regular ones, I bought the stage 1 ones on ECStuning back when car had 100k miles and now its at 166k.

 

I put some Marvel mystery oil into my gas tank and it stopped doing that. I guess it was probably something with the injectors?

 

Could be. Drive it and see if the problem comes back. Glad to see it stopped doing it though.