rich since winter started

[TG Goose]

this has only been happening since the weather changed and the weather has been floating around 0 Celsius.

When the engine is cold, it will fire up no problem, but feels like one of the cylinders is misfiring. engine shakes a little, exhaust smells really rich. Once closed loop begins, its like there is no problem at all. The only closed loop issue is a constant rev wobble from 900-1100 rpm.

I've replaced plugs (bosch silvers) wires, cap and rotor. I replaced the line to the cold start valve as well as the cold start valve itself. none of his has changed a thing. The IAC has also been replaced.

The car also diesels for 1 or 2 seconds after it is turned off.

Any help would be appreciated

[TG Goose]

changed coolant temp sender (ecu) and still no difference.

[TG Goose]

swapped out the coolant temp sensor with another one just in case and it did make a difference. Car is now even harder to start, takes more cranks, once it catches, if you give it some gas it starts to run great. definitely runs better overall, but still has a hard starting issue.

[TG Goose]

I think I solved it, the previous owner must have swapped the coolant temp sensor and thermo switch plugs. I swapped them and it starts up just like it should. Car also runs a million times better.