Erratic idle when warm

[jpearce]

I have a 2010 180 challenger 255hp. I noticed recently that in neutral when the engine is warm the rpms surge between 1800 and 2100. Only 43 hrs on the boat. Just changed the oil. Spark plugs replaced @ 20hrs, maybe i'll put a new set in to see if there is a difference. Any suggestions or ideas?

 

[johnathanrn]

Hmmm I'd say spark plugs but you changed them...maybe a problem with fuel line/pump? I no mechanic but I dabble here and there...does anyone know if these boats have fuel pumps? Maybe they need to be jetted?

 

[ruby]

seriously, somebody out there thinks you can jet your boat. its EFI and computer controled and yes it has a fuel pump but that is not your problem. it may have some trash wound up in the impeller and chances are lf you drive it more the problem will go away. it happened to me more than once, hope this helps. make sure oil level is not overfull.

 

[thor7000]

300 rpm isn't a big deal...as long as RPM's are nice and steady when wide open without any surging (up or down) then I wouldn't worry about it.

 

[jpearce]

Yeah I'm not to worried about it. just dont know why it didnt happen before. It was pretty smooth at idle. No problems at any speed, RPMs remain steady.