So I spent the better part of my free time this week installing my new big bore runners. What a pain in the A$$! If I had known what it was going to take to get these things in I would have paid someone else alot of money to do it. Well, I start it up tonight and it starts to stall out unless I rev it up to around 2500-3000. I also hear a good amount of air being sucked in. I assume this is caused by a vacuum leak. I can't get the thing to run long enough to spary TB cleaner to see where the leak is. Well, after a couple starts, it won't start at all now. Turns over but doesn't catch. Anyone else have any ideas or suggestions? I have searched around already too..to no avail

 

Get a good light and look at the install, there is a chance that the tubes are on the wrong side or that the cold start hole is not plugged.

I would look for a big vacuum leak.

 

I put the runner with the cold start injector on the driver's side. These runners came with a block off for the cold start injector. Also, I just noticed that the plug under the plenum, in the back, that is like a pigtail connector is undone. Could that be causing any problems?

 

Probably not, but you should fix it anyway. That's the MAT sensor (Manifold Air Temp).