Thread: Ok to go from a Synthetic oil, to a synthetic blend??

Originally Posted by GTPpower

You are correct about ac delco. I didn't realize they were so bad.

Here is a decent description as to why mobil 1 isn't fully synthetic.http://www.bobistheoilguy.com/forums...Number=2548209

So basically all full synthetic motor oils aren't "that great" then? Like pennzoil, castrol, mobil 1, valvoline.

Originally Posted by comatoast

Just a random thought... Do you guys think my overkill PCM might be causing issues with the cold weather with the fuel changes he makes in his PCM? Bad o2 sensor , ??

I just find it weird that it almost fires. It will crank , fire, crank, fire, but just not start. So close most of the time.. Then it floods from not starting... Maybe just swap back the original PCM, to see if it helps?

Any other suggestions?

It's definitely possible. If you still have the old one swap them and see.