My friends Audi runs sluggish sometimes. He had the oil replaced about two weeks ago and since then he has noticed the sluggishness.

New oil used was 5W-30 (Castrol Full Synthetic) and had added the BG synthetic oil based product to the oil.

I checked the DV (bypass valves and tested it and it was holding vacuum) followed procedures from this website http://www.vaglinks.com/Docs/Misc/VA...rter_Valve.pdf

Could it be the oil weight or something else? The Secondary air pump works fine as well. Any idea what to check for now?

Thanks for your help in advance.

 

You may also want to look at the fuel and air filters. They're cheap relatively to replace as starters.

 

We replaced the air filter with the K&N one and have new plugs also. The fuel filter is next to be changed but that shouldn't cause the sluggishness right?

It has been cold also so not sure if the oil has to anything with the sluggishness. is it possible to test the turboes and see if they work properly?



Thanks in advance!

 

It could. I noticed my Audi A6 was running pretty sluggish, like it was being fuel starved, so I replaced the fuel filter. That seemed to do the trick. Does the sluggishness occur when his car is first started up? If not, then my suspicion that it's fuel related.

 

He said it feel sluggish at different times. So you all suggest to change the fuel filter?

Also, we checked the turbos and we can hear it kick in.


Thanks.

 

Ordered new fuel filter and it'll be here tomorrow. Also, he said that the transmission shifts hard at the beginning then after that it's fine. Any clue on that issue or maybe needing a flush soon?

 

My 2.7T does not like very hot (> 90o) or cold (< 30o) weather and performance is less peppy and gas mileage noticeably reduced, especially in the colder weather. Your engine oil weight is appropriate. I suspect the tranny may shift a little rough until the fluid warms up. My MT6 is sticky at first for the same reasons.

 

Well we changed the fuel filter but didn't do any difference on the cold shift and still sluggish, it's hit and miss so not sure what's going on.


My buddy is going to get a transmission flush and hopefully that'll fix the cold shift issue.