Update: Cold start/idle issues

[xFatcatx]

I had a few posts about hard cold start and poor idling issues with the 99' Sport, 4.0 SOHC with about 120k miles. The idle would surge a bit and rpm's jumping up and down, it ran very rough overall. Glad to say the problem seems to be fixed, all though will have to wait for a colder morning to 100% sure. List of what I did this morning, basically needed a tune up and glad it wasnt anything major:

-new upper/lower intake manifold gaskets
-cleaned IAC
-cleaned MAF
-cleaned TB
-new plugs/wires
-new PCV Valve
-new thermostat (since I had the manifold off)

I wish I knew exactly what the issue was, but the TB and PCV were filthy, and found a small tear in one of the old plug wires. I am not sure how dirty PCV valves should get, but I am thinking this one was stock as it read motocraft on it....

I highly suggest anyone doing manifold gaskets to change your PCV while your at it as its easily accessible then, along with the thermostat. I read about people having problems with the "T" connection on the PCV, but since I had the whole thing with hoses out of the truck it was easier I guess and the new PCV easily slid right into the "T" connection. I forgot how much fun plugs were in these but with the passenger tire and splash guard off it wasnt to bad I guess.

 

[Butler8196]

I have done all the above and still have a cold idle issue. The RPM's will fluctuate between 1800 and 900 for 3 or 4 times and when put into any gear(auto), it runs rough. This only happens when cold.
Any Ideas???

 

[xFatcatx]

Sorry man I dont have any ideas, hell I was ready to just start throwing parts and money at this thing if the tune up didnt work. Hopefully my issues do not come back.