Before i got my 940t, it was running on regular, i put premium into it asap once i got the car. The oil was changed, but to 5w30 and the idles un steady. I put a fuel line cleaner in but later learned that it can clog up the fuel filter. I jus bought some Engine Restore and Seafoam. Has anyone used either on their cars? Or know any good or bad things about it. Engine Restore should take away the knock, and then the seafoam will help clean up the intake and fuel system problems before i bring it to the garage again to do some other work. ANy thoughts!?

 

I just used a bottle of seafoam in my tank and had no issue. It comes highly recommended amongst the people I know. Whether it will cure a knock i guess is just a trial and error thing, but even if it clogs a filter (which it shouldn't) you should consider doing the filter anyways.

P.S. an unsteady idle can be a lot of things though, from timing problems to vacuum pressure etc.

 

Epic Fail. I did the whole seafoam deal, in crankcase, vacuum hoses, gas. it was tough to keep the car running while putting it in, but did it, and then shut it off, let it rest for 15 min, turned it on and no smoke. Idle the smallest amount better, and had a small amount of pep to it over normal. But overall, nothing. Wat could be the issue? And it still knocks now, im thinking i need thicker oil. Any other suggestions to fix the knocking and rough idle?