Hi , my 2000 accord with a 2.3 vtec was overheating and had oil in the radiator so I changed the head gasket ( head and block checked out ok ). Now when I start the car cold it idles fine for a minute or two then it starts to idle surge up and down between 1000 rpm and 1300. Once the check engine light comes on it surge idles between 1000 rpm and 1100. Engine code p0505 and p1519 come up. If I spray starter fluid around the engine idle stays the same. If I spray a lot into the throttle body intake hose the idle goes up and smooths out some. If I disconnect the iac valve there is no change. I checked all my connections and vacuum lines one at a time and they are all good. If I create a vacuum leak it amplifies the idle surging. I bled the coolant system out and have coolant running through the fitv under the throttle body. Motor revs above idle fine and drives fine too . Any ideas ? Thanks , Matt .

 

P1519 is for the IACV circuit.
P0505 is general idle-control system problem (probably caused by the P1519 problem).

Unplugging the IACV should cause it to almost stall, so that's not OK. But a 2000 Accord isn't supposed to have an FITV...?? There IS a coolant hose connected under the throttlebody, but it's not an FITV.

You should probably go over the whole idle control system, I suspect that with a non-working IACV someone may have compensated by adjusting the idle screw or something.

 

Thanks for the reply Jim . I ended up cleaning the throttle body and pulled the coolant line going to the throttle body and checked it for coolant which was present . The other thing that came to mind was that I power washed the hell out of the rad and engine coolant system to get all the oil out of it , so the wiring all got soaked . The car sat in the sun for two days before I clean the throttle body and checked the coolant hose , but when I started it up it ran fine again , so I am not postive which thing I did that fixed it or didn't do . But it works great now . So all set .

 

Good to hear it works now.

The way I look at it, general cleaning isn't a waste of time, no matter what actually caused the problem.