2003 Sohc miss fire

[2003GoldSporttra]

It misses very slightly when engine cold. It seems to get worse when it warms up. I was reading that the earlier models had a problem with the intake maniforld gaskets leaking and letting engine coolant down into the cylinders. Causing the miss fire. I'm trying to find out if the problem was corrected with the new generation 4.0L.

 

[IZwack]

If coolant is going into a cylinder:

1) you should be low on coolant
2) you should see some white smoke in the exhaust (although it might not be so obvious if the leak is small).

However, I dont believe coolant is the issue as the 4.0L SOHC has had a pretty good run since its introduction back in (I think) 1997. If the Check Engine Light isnt on, I would check for the obvious like a loose/cracked vaccum hose, loose wires, and then maybe clean the idle air control valve - IAC (search for this, its a popular item to cause problems).