Random starting problem

[rem_pss308]

1999 X-star LTR motor
This past weekend I had a random problem. it did it a couple of times during the day.
Motor turns over and starts but idles rough and shuts off. after a few trys, let it sit. then it starts and idles up like its supposed to and runs smooth. motor runs great after it stays running.
buddy said it might be a mass air flow senser.

anyone have any ideas?

thanks

[JimN]

1999 X-star LTR motor
This past weekend I had a random problem. it did it a couple of times during the day.
Motor turns over and starts but idles rough and shuts off. after a few trys, let it sit. then it starts and idles up like its supposed to and runs smooth. motor runs great after it stays running.
buddy said it might be a mass air flow senser.

anyone have any ideas?

thanks

You don't have a mass air flow sensor.

If it happens again, open the throttle and see if it starts immediately. If it does, scan for codes and look for 14 or 15 (most likely will see 15). If the exhaust smelled strongly of gasoline, I would suspect this- it means the ECT (Engine Coolant Temperature) sensor may be bad. If you have a muti-meter, set it to read resistance and measure the sensor- it should be around 240 Ohms @ 194°F. If it's much higher, the ECM thinks the engine is very cold and will deliver too much fuel, which requires more air to burn efficiently.

This sensor has two wires- one yellow, one black. It won't show up on the gauge because this sensor is only for engine management.

[Cumminscj]

Jim is a smart guy, do what he says. And maybe look for corrosion on the pins of the sensor while you are at it

[rem_pss308]

Thanks for the reply JimN

I hope to get it back on the river next week. When you say open the throttle, are you talking about open it, then back to neutral, then try to start it. or am I able to crank it with throttle opened some, by pulling out the button, and giving it throttle with out putting in gear?

I cant scan for code. my check engine light doesn't work. ( found this out when ECM went bad a few years back )

Unless there is another way to scan...

where is this sensor located on the engine?


Yes Cumminscj JimN is very smart when it comes to these boat problems. I'm very glad he responded. his answers are always calculated responses. not guesses. I'm guessing he worked somewhere as a technician.

[JimN]

Thanks for the reply JimN

I hope to get it back on the river next week. When you say open the throttle, are you talking about open it, then back to neutral, then try to start it. or am I able to crank it with throttle opened some, by pulling out the button, and giving it throttle with out putting in gear?

I cant scan for code. my check engine light doesn't work. ( found this out when ECM went bad a few years back )

Unless there is another way to scan...

where is this sensor located on the engine?


Yes Cumminscj JimN is very smart when it comes to these boat problems. I'm very glad he responded. his answers are always calculated responses. not guesses. I'm guessing he worked somewhere as a technician.

The ECT is mounted in one of the heads- I think it's the left one as you look from the rear of the engine.

You can test the bulb- leave the ground wire and connect the other to 12V. The problem wasn't the bulb, it was the harness supplier, dealers who didn't fix it and the original boat owners who didn't do anything if they got a notice. IIRC, you would need to unplug the boat harness and find the wire that's conected to the light (briwn/white)Then, you need to find the corresponding wire in the DLC at the rear of the engine (terminal E, brown/white). Cut the wire on both sides of the plug and install a weatherproof connector. The light should now work properly.

If you don't want to splice the wires (I don't know why you wouldn't- it IS a warning light, after all), you can scan for codes by inserting a pper clip into terminals A and B while a lest light is connected to terminals E and F.

[Cumminscj]

Ect is mounted in the intake by the thermostat. In attached pic of course the thermostat isn't installed. See right side of the pic