jonnynh

Hi Audi world, this is my first time posting but I have been reading here for years. I have a question about my turbo and I'm wondering if I can get some explanation from someone who knows more about this than I.

Turbo Symptoms: During hard acceleration the turbo boost will fade toward the upper rpm's and I will see a thick blue cloud of smoke engulf the road behind me. This does not happen on every hard acceleration. when it's not happening the car accelerates like nothing is wrong through the whole rpm range.

I called up my local dealership and they said from the symptoms that the turbo should be replaced ($2500) as the wastegate valve seemed to be bad. Does that make sense?

Does anyone think these symptoms could be the $50 N75 wastgate frequency control valve?

Thanks for any help - Jon

jonnynh

Summary of resolution:

It turns out that the seals along the turbo shaft went causing oil to leak into the exhaust as well as into the compressor side of turbo leading into the engine air intake. when i took apart the engine intake tubes below the compressor about a quart of oil poured out. that's when i knew it was not a simple N75 valve.

I took it to the dealership and they found the same symptoms and replaced the turbo with a re-manufactured turbo. total cost with labor was $2,150 and its running well again. my car is a 2007 a4 2.0t with 97k on it. the dealership said a bunch of turbos on these cars were going around 90k. fun stuff