SR20 Fresh rebuild, delayed throttle, rough idle

[MrSlappy]

So I just rebuilt my S13 blacktop SR20 and on start up it had the following problems: extremely rough idle, slow throttle response, and light gray smoke coming from what would seem to be where the turbo meets the manifold. The car has stock fuel system, ecu, maf, etc. On the rebuild I used: same rods & pistons, reman crank, oem piston rings, clevite bearings, oem oil pump, Tomei 256 poncams. I may have missed something, but I caught myself searching pretty extensively (both google, and zilvia). I found people with similar problems, but only caused by the installation and/or changes to maf, injectors, ecu, and so forth. Timing seemed right, and I played with the cas. That made it better, but not how it should be. I'm really at ends here. Hopefully an SR guru can help. This is my first installation & while I have done more than enough research, I do lack experience. Also, it's not a vacuum leak. This is much worse than a vacuum leak. Thanks in advance - Alex

[ShadowMan]

You say it was a complete OEM rebuild EXCEPT for the
-cams
-bearings
-reman(ufactured) crank, as in how? what did you have done to it?
Aside from this list, it's all OEM, right?

You typed "Timing seemed right, and I played with the cas. That made it better, but not how it should be."
Narrow it down for us by eliminating what it's not. You plenty capable to:
-compression test it
-check your spark
-check fuel pressure
-see what your afr's are telling you
-check timing
Sounds like a timing issue. Double and Triple check that. Make sure you did not skip a tooth.
Also sounds like you need a timing light. Grey smoke coming off exhaust manifold is probably
all the residue from you touching it with oily hands. Make sure all your harness clips are fully seated as well. Maybe your maf took a shit. Unplug it and see if the idle changes. Right now it could be a few different things causing your problems.

[Danger_Dorn]

Could be many things...we need these things: compression test, afr, verified spark and injection, unplug maf what happens, unplug tps what happens. This sounds kinda like a TPS, maf, or boost leak. The gray coming from your turbo is probably exhaust. Replace the gasket and bolt it up (make sure they are strong bolts) otherwise they will break or shear off...which is terrible

[Danger_Dorn]

Also that leak between the turbo and dp will KILL your turbo. :ddog: Fix that soon

[ultimateirving]

You can start also by checking base settings.

What is timing at with a timing gun?
what is TPS voltage closed and open?
what is maf voltage while idling?
What codes are showing up on the ECU?
What happens under load?

If you did the swap its possible there could be some grounds you might have overlooked.