Rich Lurz

idling down the lake last weekend and I got the dreaded two beep alarm. Took the boat home and scanned codes. only code was for the IAC output. Replaced the IAC and still have a no start situation.After clearing the code and cranking the motor [still no start] I get the IAC code back again. As I sat scratching my head, I cleared the code again and the alarm went off again with the ignition on and the boat not running and the code was back in the scanner. Scratching my head again I noticed my alarm is sounding every time I turn the ignition to the on position. When the ignition is turned to the on position I initially get three beeps then the intermittent two beeps?Thunderstorm just rolled in so I am typing instead of wrenching. Any ideas?

Sydwayz

iTrader: (1)

Check the IAC connector. They are also known to melt the pins, short, AND can fry the driver on the ECU. Dustin Whipple at www.whipplesuperchargers.com CAN fix this issue, but it requires sending in your ECU, or you buying another one.

Swap your ECU from one motor to the other, and see if the problem follows.

Other threads; same topic:

http://www.offshoreonly.com/forums/g...-what-now.html

http://www.offshoreonly.com/forums/d...elp-again.html

Rich Lurz

Thanks Sydwayz, I suspect the ECU also. Connector at the IAC does not look melted or shorted. plastic melted out of the solenoid at the connector but does not appear to be the connector itself. I will check wiring, connector at harness and swap ECU tonight. Unfortunately my money rides on the ECU.

sutphen 30

the 2 biggies for no start on those engine are the crank and cam sensor.I 'd start w/ the crank,plus its easy to switch from the other motor.

Sydwayz

iTrader: (1)

Strong point. I was focused on the IAC codes. See this thread of what I just went through:
http://www.offshoreonly.com/forums/g...0-400-rpm.html

My CPS was bad, and throwing no codes. It would start and run though, but things were not right.

BUP

iTrader: (9)

Bad crank PS you will not have a tach reading most of the times.. Possible cam PS or connection. The cam sensor is also a hall effect sensor with the same type circuits as the crank PS, the cam & crank sensor work together for input to the PCM. This allows the PCM to know which one of each of the pistons is at TDC on the compression stroke - 1/6 - 8/5 - 7/4 - 2/3. Any loss of the cam PS can result in longer cranking times or a no start issue since the PCM can not figure out which stroke the pistons are on. Anyways this is the a very short jist of the Cam PS.

Also try starting your engine at half throttle or above to see if it will at least pop off. If the IAC or it cavity is plugged - moving to half throttle or above always air into the motor. How dirty is the cavity the IAC muffler sits in ? Is the IAC muffler in place ?

You could have a bad IAC again right out of the box. Also bad connector or connection to IAC or even to the cam PS. If the connectors get any moisture internally they can cause a no start issue especially with Cam & Crank PS the same goes for corrosion. Not uncommon.

not knowing your year of engines or engine serial # - if you have 10 pin engine wire harness (mechanical - Non DTS) make sure the pin connection(s) for the PCM and harness plug in to it is in good shape plus no shorts / corrosion. The IAC / PCM location is B7 for it - If I recall Black / green wire and the red wire goes to wiring / harness splice 105.

Make sure your kill lanyard is working correctly so check for spark or no spark issues.

Next a bad IAC over time can hurt the PCM as well. possible bad computer / bad internal ground.

First try is to see if this engine will start at half throttle or above -be prepared to reduce your rpms ASAP if it does start.

Rich Lurz

Bup, thanks for input. Tried the half throttle - no start. Only code coming up is IAC and the code comes right back after I clear the code without even attempting to fire the engine.

Rich Lurz

04 serial # om693051

BUP

iTrader: (9)

99% of Sunny 32's have twin engines. Do U have twins. I would change your working IAC over first to see what happens. If not then swap over working PCM if your other side engine starts and runs very well.

Just asking do you have fuel pressure and spark on your no start engine. Oh do not mix them together or kaboom.

Also heads up when ever swapping ECM / PCM - always unhook battery power before touching & installing them and watch of for staticelectric discharge from yourself and any other source while handling them.

Next freaking thing is bad coils can knock out an computer right on the spot while cranking the engine over after the computer swap. I have seen it happen and heard from others that it has happen to. The older 496 coils sometimes go bad more often than the newer style on the 496.

Check all your grounds especially backside engine, make sure your battery is good (12.7v), make sure all your connections to computer and sensors are good / corrosion free / no moisture / tight and no shorts, Man hopefully you do not have a bad PCM.

Rich Lurz

BUP, twins. Already replaced IAC. My money rides on the PCM. Will swap tonight.