Help! I've done just about everything! Engine hesitation

[DatPurpleE30]

Hello there, long time listener, first time caller. My name is Tyler, I have 1990 325i That has a horrible habit of hesitating, mid throttle. I've replaced all my secondary ignition (spark plugs, spark plug wires, dis cap, rotor, coil, etc.). Also replaced my intake boot and hoses to make sure it wasn't a vaccum leak. Checked my injector harness too, I took the harness off and isolated each individual injector so that corrosion wouldn't happen anymore. replaced my flow meter and tuned my tps. I have no where else to go with this. I'm stuck. And extremely irritated.
Things to keep in mind
-only happens in colder weather
-engine cold or warm
-started after I did my 5 speed swap
-fuel pump and filter is new
-mid range throttle only, between 2-4K rpms mostly
-if I turn the car off in the middle of it doing it and turn it back on it will stop
-if it's happening and I give it full throttle it will stop asking as I'm giving it full throttle.

Somebody please help me before I drive the thing off a cliff with me in it.

[cirrusblue]

This prob. is not it, but I'd replace the ecu and fuel relays while I've done all of this. It's pretty cheap. Have you looked at your ECU too? Tried a new chip, something in case it's not sending the engine info. Does your OBC report the correct outside temperature?

[Cephas]

http://www.r3vlimited.com/board/showpost.php?p=4472783&postcount=27

Read that thread and do 2 things. Check your crankshaft position sensor first. Check the ohms and check the distance to the flywheel. In this thread, it ended up being the harness - he bought used and it didn't help, so he ended up buying a new one. Good luck!

[modernist]

When was your oxygen sensor last replaced?

[Kershaw]

Been there, done that. I replaced everything in my engine bay. The harness, injectors, cps, afm, tps, took like a week. Nothing changed, the car wasn't even driveable it stuttered so badly.

Then I replaced the harmonic balancer because I had nothing else and suddenly it was 99.99% fine. I get small misses here and there still. When I eventually get it back on the road the first thing I'll check is the CPS distance.

[audiquattrot]

btdt. My issue ended up being the ICV. Replaced it w/ a brand new one, and my hesitation issue went away. Cleaning the ICV didn't do anything, that's why I bit the bullet and bought a new one.

[Kershaw]

Even under load or wot? How would the icv affect that?