2004 Mercury 225 Optimax

Hello,

I have a problem when starting my engine, it revs up to like 1200 rpm for a second, or sometimes actually stalls when starting. It kind of reminds me of a choke sticking on a carburated engine.

After a few seconds, the RPMs drop back to normal.

Most of the time if I am idling around, it idles fine. At some times, it seems to be missing.

The engine is running great when going all out.

I have recently replaced the plugs, plug wires and Fuel Filter.

I have a hotfoot peddle installed. At first I thought this may be sticking but I verified it is not. I put a new throttle cable in about 6 months ago.

From what I have read, it appears to be the Throttle Position Sensor.

About to find out after spending 180 bucks to order one. Hopefully, they will take it back if this is not the issue.

Any other thoughts?

I had a similar problem about a year ago where the Tracker valve was bad but the symptom was a bit different. The speed at idle constantly changed from around 600 to 1200 and back over and over again.

Re: 2004 Mercury 225 Optimax

bump

Re: 2004 Mercury 225 Optimax

Well after paying 194 dollars for the Throttle Position Indicator and putting it in, I still have the issue.

I was excited at first since the TPI had some electronic type of sealant leaking out of it, so I thought for sure this would be the problem, but it wasn't. My guess is it would have went bad soon anyhow since the sealant was leaking out of it.

Any other ideas before I take to my mechanic and blow another grand on the engine?

Re: 2004 Mercury 225 Optimax

I can't say that I have any experience with an Optimax, but you may have a dirty filter, such as item #49 in this diagram?
http://www.boats.net/parts/search/M...0T801000 THRU 1B417701/Air Handler/parts.html

This is just a guess, but worth investigating

Re: 2004 Mercury 225 Optimax

Thanks I'll give that a try next. I had already replaced my fuel water separator(filter).