DF200TXK5 only starts on ether

[cajunmech]

Looking for some help here..... I am brand new to this site.
I am working on a DF200 TXK5. The engine runs fine once it is started. However, when it is shut off it will not re-start. The only way I can get it to start is on ether...... Here is the history, boat was at a shop and sat there for a long time. The guy(who I am helping )went to pick it up because they were not getting the job done or letting him know what was going on. The Boat was in for seasonal maintenance. He saw his boat there and a bunch of stuff was missing off his boat. Radio,speakers, throttle control, control cables, prop, starter motor, wire harness, as far as I know. After working with that shop.... they put it back together with used parts minus a starter, and he took the boat. This is the point where I came in..... I got him a starter, installed it, then checked over the engine did basic stuff, oil and filter change, primer bulb, fuel filter, water separator filter, water pump change, and a trim switch(that was not working) Drained the old fuel added fresh fuel along with some star-tron. New spark plugs and also did a compression test. Which was okay. Repaired a bunch of cut wires under the console but all that was boat related. Test ran the engine, started and ran fine in the water. He used the boat for about a week no issues, then Ran the engine out of fuel. He put 10 gallons back in, could not get to start. I got it started after pulling off the primer bulb pumped some fuel through the bulb, hooked it back, also put on a fuel/water separator thinking, maybe.....water? Dumped the fuel filter catch bowl(had a little sediment in it, filter looked good. Engine started up and ran for about an hour no issues, parked boat would not restart the next day. Pulled off the primer bulb again, bulb was pumped up, pumped fuel through it again, hooked it back up, primed up bulb, engine started. Ran about 1 hour fine. Shut off, would not restart again. Now If I give it a shot of ether starts right up continues to run and idle however only way to restart is ether.
I removed the VST. thinking maybe foat was sticking, VST did have some junk in it.
Just looking at advice where to go from here. Any suggestions would be appreciated. Thank You.

[redlowrey]

With the key on check the voltage on the two temp sensors and the exhaust temp sensor.
There are three wires on the map sensor, red,white, And black with a white stripe.
note the voltages and come back on the forum.

You would think that it was fuel related with the primer, but if you turned the engine off each time that would have left fuel in the vst so it should have started on its own

Don’t disconnect them key on connected.

[cajunmech]

Just getting back to this........ Since I had the VST off it needed a new seal ring(old one rotten). Replaced that and also the float valve and cleaned the internals of the VST. Put that back on. Also was thinking low voltage and I tested the battery. Fully charged it tested on the verge of bad, so I replaced the battery according to Suzuki specs. It was a lot larger battery than the boat had. So new battery in and VST cleaned tried to start it. Engine would fire for a second and then shut off. So like a VVVVroom...then stop. Best I can think of for description. Before the new battery and VST clean it would only turn over.....
Next I tested the sensors you listed. EX temp sensor port side, 2.106V. EX temp sensor Starboard 2.091V. Clylinder temp sensor 2.060V. Map sensor Red 4.95,black .007 and white 3.95.
I have not looked at the service manual for the specs on this, so I will be trying to figure this out as I am also seeing what your thoughts are. Thanks.

[redlowrey]

When I read your first post it sounded like the computer not injecting enough fuel on start up, looking at that temp sensor voltage to me it is a volt too low. The map sensor signal seems right for key on engine off, the exhaust temp seem just a bit low, but the main input is temp sensor voltage. What is the ambient temp where you are if it is around 25c that temp voltage should be closer to 3 volts.

I also need to know the voltage of the iat sensor, and what the throttle signal voltage is, closed throttle should be under 1 volt, before you replace anything if you want to cheat, get a half watt 2kohm resistor remove the temp sensor plug and bridge it, turn the key on and check what the voltage is, if under 4 volts crank the engine and it should start.

If it don't start come back on the forum let me know what you have done, I don't know what the temp is where you are so put it this way if you were in the arctic the computer would want to see 4 volts on the temp sensor, if you were in the Bahamas maybe just under 3 volts do you get the drift. It sounds like it is injecting for a hot start not a cold start.

[cajunmech]

Question.... Is the throttle plate on the throttle bodies supposed to be completely closed on start? I am not understanding this in the service manual. It almost is written that the plate is supposed to open when the key is turned on....? Then adjust itself? When the key is turned on now the plate is completely closed. Operation is normal with the throttle lever/linkages are okay. I did test the IAC and it is testing within spec.
I'll get back with you on the other voltage tests. Ambient temp. is between 80-90F.

[cajunmech]

Also, I hope I just didn't make a mistake...... I thought I would check spark, hooked up my spark tester. It is a snap-on brand tester. It plugs into the cap and has a screw adjuster to check spark gap. Other end goes to a ground. I tried that and it did not spark. I then took one of the old spark plugs and grounded that to the engine. It had a flash of spark, not a spark to the electrode tip, just a bright flash..... It worked like this on a few of the cylinders I tested port side, then third cylinder had nothing. I went back and checked one and 2 and is no longer sparking.......

[cajunmech]

Here are the tests, All seem to be good, however I left the key on and tested all these at once. I just happened to put my hand on the IAC and it was hot! Put my laser temp reader on it and the top of it read 140 degrees. The key was on the whole time I was testing these. It was probably about 10-15 min. IAC failure?
Tests:
1.Temp sensor V 2.196V
2. EX temp sensor volts (port)2.24V (star)2.22V
3.IAT 2.31
4. Throttle signal voltage .714 FCT 3.307WOT

[cajunmech]

GOT IT!!!!! It was the IAC. Took the old one off and it looked to be fully extended. It did not do anything when the key was turned on or off. I picked up a new one, installed it and it fired right up. Going to run it on the hose now....... Then take it for a lake test.
Thanks for the help, knock on wood......Think i'm in the clear!

[redlowrey]

I am a bit confused if you had no spark spraying ether would not help. With the throttle it has a base idle setting, and depending on information from the temp sensor will depend on how much air the iac will bypass for a cold start.
Usually with an extended pintle, having no extra air bypassing the throttle plate on a cold start, spraying any hydrocarbon makes it worse, good to see you fixed it.
.

[cajunmech]

I looked at the spark initially and it had spark, I did not think it was a spark issue since the engine would run okay once started. I was thinking maybe.....there was an issue with all cylinders sparking during start up an possible that could be an issue...... So I just went back and started to check each cylinder for spark after I was doing all of the other checks. That is when I noticed after checking 2 of the cylinders I did not have spark on the #3. I went back and checked #1 and #2 and it did not have spark again. I am not exactly sure what happened there. It is obviously sparking okay now, since I installed the new IAC it started right up. No hesitation, starts as soon as the key is turned, I did not water test yet, had a big storm roll through yesterday. Hopefully I can get out today.
I will get back with the water test results. Also I am still wondering why it would not start do to bad IAC. I need to look into that concerning how that was causing a non start and it would start with the ether..... Thanks again!