KA24de struggles under 2k

[WithHonor037]

I have eveything squared away as far as the idle. The car idles great. But once it warms up then it sputters and runs excessively rich. I ordered new plugs, wires, and an oxygen sensor to see if this has any effect. I did discover that the IAC valve appears to be missing. I have an electrical connector that doesnt plug into anything near the coolant resivoir as well as a large vacuum line with no apparent connection. When I bought the vehicle It had no intake so I had to suppply my own. Could the IAC be why it struggles to accelerate and stalls on decel? Anyone have any suggestions? Ive searched around and havent found anything that gave me real solid information.

[gian52]

does it pass 2k or does it get stuck on it

[WithHonor037]

It will rev all the way to the limiter. Once over 2k rpms it seems to run better. Occasionally the throttle bogs while holding it open at a constant rpm. But it runs alot smoother.

[OutToWinPAHC]

If you have an open vacuum line and no IAC that is one big issue. I'd fix those ASAP, then try and pull codes if you have any.

[WithHonor037]

I have a pcv valve in the vacuum line currently to help maintain the negative crank pressure. Without it in there the car idles high. Around 1100 rpms. It seems like the car leans itself out without it in. Just a theory. But I saw that the IAC can be blocked off and I wanted to see if theres actually anything wrong with it before spending all that money on a part that may not even be bad. Any suggestions for testing the IAC. Im not even positive its missing but I dont see a connection for the vacuum line. Does anyone know how all of it is intended to work. All I know is the brief description the feild manual offers.

[OutToWinPAHC]

Factory service manuals.
the-ultimate-sticky-read-before-posting ... 41882.html

[WithHonor037]

The factory manuals are only good for technical definitions. Already read through all of them anyway. I was hoping someone had some experience with a similar problem.

[WithHonor037]

Alright so the IAC is intact and now reattached properly. New oxygen sensor is installed. Still no change though. Is there anything I may be overlooking? The previous mechanic changed the injectors and Im currently leaning towards that as a culprit. Any other suggestions anyone?

[raven2345]

Only a few random things come to mind for me, because my car is pretty much hacked up. Faulty TPS, or maybe a MAF or coolant temp sensor flat spot or something along those lines.

[WithHonor037]

I thought about the MAF too. Especially since I had to build an intake for the car myself.Maybe there is something with the airflow. But Im not sure how to test it.

[WithHonor037]

So now I discovered theres low vacuum pressure.