97 GT40 high idle?

[weknds]

Engine seems to idle high though nit consistently. Anywhere from 750- 1100 rpm. Changed fuel filter this season. Also checked to see that cable is returning to stop. Any thoughts ?

[newfoundskier]

I have a 97 GT-40 as well and when I put the boat in neutral the rpm's will surge to 1000 or so rpm before settling down to 700 or so RPM's. I've read about it before on this board and someone said there is a fix but I do not know what that would be.

Everything seemed normal to me until I changed my spark plugs and starter solenoid.

[jthooker]

97 GT-40 High Idle

I put up with that on my '97 SN GT-40 from the day it was new.
Finally solved the problem by trading it in on my new '04 SN.
The service rep at PCM always claimed that the behavior was
programmed into the engine control computer and couldn't be changed.
The most aggravating high idle time occurred immediately following
each start of the engine and required you to wait until the engine
slowed down from about 2000 RPM before shifting into gear.

[inboardsonly]

RE: 97 GT-40 High Idle

I believe what you are experiencing is the idle stabilization circuit.
Some are faster to react than others. Mine is ok, (95) but others of the same year that I have driven often take longer...

Mine goes up to maybe 1000 rpm, and then drops after 3 or 4 seconds.

Only aggravating when someone starts the engine and slams it into gear, but they usually only get away with doing it once.

[SGY]

RE: 97 GT-40 High Idle

It's called idle flare. I read somewhere that there was a fix. It was fixed by PCM for the 98 model year.

[weknds]

I agree with what your describe. Thats definately the problem. And yes some have been known to slam it into gear when the idle is still high. Before I throw this infrequent driver out of the boat for good I would like to find a fix. Anyone have further insight to the fix or what's different on a 98 GT40

[nms1991]

PCM and Ford changed the programing in the ecm to cure the idle problems and other issues they did not like in the programming. But the problem may be a sticking air bypass valve also.