Offshoreonly.com - 525 suddenly runs rough. Help.

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Had a similiar problem but on a 700. Had SmartCraft and it said IAC output failure. I changed the IAC and the motor ran the same. Turnes out that something took out the IAC driver in the ECU. Had Dustin remap the driver and it ran fine. Just something to check..

Did a code read out. Nothing conclusive. Leak down is next, and since there is a "noise", whistling, houwling sound that goes away with valve cover plug removed, seems like valve issues. F'ing CMI's again. GGGRRRRrrr

Quote:

Originally Posted by PARADOX (Post 3736960)

Not about to use a blow torch, but thanks. No heating issues, how do I know if I got some gasket parts in the engine? and where would it go? BTW no O ring, typ. head gaskets on 525's. Oil is is ok.

not a lit torch:whistle:........you just use the gas from it with a hose attached to the tip,,with the engine running the gas is heavier then air and it will seep into the vacume leak..or you could use carb or brake cleaner and phuck up the color of the blue paint..this is why i use the gas from a propane torch,,,it dont phuck anything up..when it seeps into the leak the engine will smooth out and thats how you can tell if its a vacume leak..the whistle from the valve cover could just be coming from the pcv hose whistleing and when you take the oil cover off it goes away..