Not fast, engine rough.


Active Member
So we have almost everything hooked up and were driving. There are a couple vacuum lines still hanging but the engine running nice, that is, until we plug in the maf sensor. Also it runs ok but also has no boost, but we can hear the turbo is working minimally, maybe 1 or 2 lbs. The guy that used to own the car did some work putting a new block, upgrading to an oil cooled borgwarner turbo and he said he's had the same problem before. His recommendation? Let the car idle for 25 minutes and see if that fixes it. I told him it starts to idle real bad once we plug in the MAF and dies but he mentioned trying to give it just enough gas to keep it going.
Any engine guys have any ideas on if this sound right or what we might check? I'm pretty sure we have the maf sensor in a good long section of pipe and its facing the right direction.

Thanks for the help!


Goblin Guru
While this probably isn't your problem, I'd plug the vacuum lines. Those lines will suck additional unmetered air at idle which might cause problems.

Make sure the MAF is clean and facing the right direction. I have a spare that I could send you.

And yes, determining what codes you have will be a big help. Air flow codes will disable boost.


Staff member
Post images of your complete turbo setup. Yours is not stock so to get it working properly we will need to see all of your components.


Make sure the Maf is facing the right direction. There s an arrow on top that indicates air flow direction. And the pipe cannot be a different diameter than stock, or you’ll need to program the difference.