96 Corsica 2.2 cold start fuel problem HELP!!

[sixwillwin]

1996 2.2L Corsica troubles
- NEW in last month - fuel pump and FP regulator
- NEW in last 3 months - plugs, wires, water pump
- NEW - O2 sensor and coolant temp sensor last week

Car starts and runs great EXCEPT---------

When its below 15 or 20* it starts but barely and then struggles to run like its too rich - then leans out? and runs normal

When its below 0 or 5* - it will not start - pops like it wants too- seems too rich again - wont start

3 times now I have put it in my shop, removed the FUEL soaked plugs - dried them and reinstalled - then car starts normal - 3 times I have done this - while plugs are out, I have someone crank engine and all fuel injectors seem to be pulsing noramlly and evenly

SO-------------------to me it seems it is getting way too much fuel in cold weather condition (or maybe too weak of a spark???) I checked plug spark visually and they seem fine.

Code that I keep getting is PO172 - "fuel bank trim condition"

UPDATE - seems to be getting worse, now temps in the 30s cause the same rich type starting problems - Some guys have mentioned replacing the ECM unit?

[forextrader]

Hi,

First thing I would do is check the fuel pressure. Even though you say you changed the pump already I have gotten pumps and they quit a month later. Did you change the fuel filter? If not this can restrict your pressure a great deal if its partially plugged. If its popping like a backfire it would more than likely be a lean condition, hence not enough fuel, which is what it sounds like to me especially since you said the plugs look normal. If it were running rich they would be soot colored (black). Also I would check for vacuum leaks as well, particularly at the back part of the TBI unit where the vacuum lines are.

[sixwillwin]

Fuel filter was changed when the fuel pump was changed. Fuel pump was changed after this problem started (it was only 6 months old and under warranty). Problem remained the same after the swap. I guess I am assuming it is way too rich, plugs get FUEL soaked and when they get pulled out and dried, it immediately starts right up.

What about this, this problem all started this fall/winter AFTER i changed the plugs out when I was doing the water pump/serp. belt. What are the chances a plug or 2 is bad or weak? I checked the spark visually and they are all firing but I dont know, just trying to pin down when this started. I may just get another set of plugs anyway, these stupid ones were $6+ each though ---AC's. I could try a regular cheaper plug......If I do, would one step hotter plug hurt anything?