Replaced IAC Valve and it worked a little....

[04select2000]

I have a 2004 Sea Ray Select 200 with a 5.0 MPI. I posted last weekend that our boat wouldn't idle and and start without pumping the throttle. I was also getting an under dash alarm.

I replaced the IAC valve this weekend and it seemed to be the fix. It started right up and ran well most of the day, until about 6 PM we untied and I went to start it and it wouldn't start. It was doing the same thing. I finally got it started after about 15 minutes and than it ran fine (idling and at high RPM's). Plus there was no alarm.

What could this possibly be? Maybe a fuel pump issue?

 

[Bondo]

Re: Replaced IAC Valve and it worked a little....

Ayuh,... When was it last given a Full,+ Complete Tune Up,+ Service,..??

 

[fossill]

Re: Replaced IAC Valve and it worked a little....

With electronic fuel injection you really need a strong grasp of mechanics along with the electronic injection system itself to properly troubleshoot. If you're so inclined, you need the merc manual, a scan tool, and a high impedance multimeter.....very important or you risk frying the ecu, and take it from there. All the diagnostic/troubleshooting steps are in the manual and if you follow them to a T, it should lead you to the problem.

 

[fossill]

Re: Replaced IAC Valve and it worked a little....

oh, and start with the basics as per Bond- O before you get carried away with the electronic stuff.

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

Its an 04 with 223 hours, I never have had tuned up, I have done all of the oil changes and maitenence stuff myself. I guess I just need to take it to get it looked at. Darn it, I thought the IAC replacement would fix it.

 

[Bondo]

Re: Replaced IAC Valve and it worked a little....

I guess I just need to take it to get it looked at. Darn it,

Ayuh,... At 6 Years,+ 250 Hours, it might just be the simple Cap, Rotor,+ Sparkplugs....
Test the plug wires, etc....

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

Gotcha, would something like cap or rottor be a problem that comes and goes?

 

[NHGuy]

Re: Replaced IAC Valve and it worked a little....

I'd look up the normal service and do whatever isn't up to date. Or at least inspect where those items may have a need.
What is the service interval for spark plugs? Does it have ignition wires or coil on plug? Does it have a distributor cap? Rotor? Does it use a regular air filter or a flame arrestor? Flame arrestors can clog up and cause a little restriction. You clean them off the motor with carb cleaner then blow dry. Does it have a PCV valve? PCV shouldn't matter much unless the EFI uses engine vacuum as a control value. But if it has one change it, they are cheap.
Does it have a check engine light? If it's on you will want to find out the trouble code.

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

No check engine light, but alarm did go off last weekend before I changed the IAC Valve, but there was no alarm this weekend. It is a 5.0 MPI, I think it has a distributor cap and rotor. It has a flame arrestor, I will try changing it.

It just gets me that the issue comes and goes. It happend once last year, but I thought it was bad gas. We use our boat every weekend and it didn't rear its ugly face until Memorial day weekend. Everyone I talked to thought it was the IAC valve. I changed it Saturday and the boat ran great for the first half of the day, and then the symptoms returned. Once I got it stated, it ran great again. Weird, Weird, Weird.

 

[fossill]

Re: Replaced IAC Valve and it worked a little....

As mentioned above start by giving it a thorough major tune up. Also, make sure the battery is up to snuff and all connections super clean. Might sound goofy, but thats the first thing we always checked when I worked on efi. You can get a scan tool and fuel pressure gage from a local auto parts shop and take it with you next time you're out along with the manual in case it acts up. Thats the time to troubleshoot it when it has a "hard fault", but to do that everything else needs to be up to par.

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

Appreciate at it. I guess I will give it a tune up next weekend. I have changed spark plugs and wires before, does a EFI motor have a rotor??? How big of a deal is it to change a rotor, cap, and time it?

 

[fossill]

Re: Replaced IAC Valve and it worked a little....

If its got a distributor its got a rotor. Newer efi has individual coil packs. Grab the manual and read up on it. It's very easy.

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

OK, manuall is down the lake with the boat about 190 miles away, I will have to get after it next weekend. Appreciate the help

 

[Bondo]

Re: Replaced IAC Valve and it worked a little....

OK, manuall is down the lake with the boat about 190 miles away,

Ayuh,... I'm pretty sure that manual is available up in the Adults Only section at the top of this forum...

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

Perfect, thanks

 

[NHGuy]

Re: Replaced IAC Valve and it worked a little....

And, if it actually did kill 2 IAC's look up that in troubleshooting. You may have found a symptom, now you want to fix the problem.
Most manuals will give you a diagnostic process, follow it to save extra steps and time.

 

[04select2000]

Re: Replaced IAC Valve and it worked a little....

Man I hope thats not the case