IAC problems

[muc]

Yes it looks like the ECM is bad. But it also seems like you might be using the manual for an EGC engine and I'm guessing you have a MEFI engine. The best I can remember the IAC circuit works about the same between these two engines, but Like I said earlier "it's best not to guess on expensive no longer availible parts"

I would be interested in what the scan tool is showing for IAC counts when the engine is running.

If you have your hull identifcation number, I can sometimes get the engine serial number with that.

 

[bhamdale]

Yes it looks like the ECM is bad. But it also seems like you might be using the manual for an EGC engine and I'm guessing you have a MEFI engine. The best I can remember the IAC circuit works about the same between these two engines, but Like I said earlier "it's best not to guess on expensive no longer availible parts"

I would be interested in what the scan tool is showing for IAC counts when the engine is running.

If you have your hull identifcation number, I can sometimes get the engine serial number with that.

The hull # fgb43568g506. The boat mechanic at the marina where I keep the boat scanned it when the problem occurred and said there were no codes. He test drove it and confirmed the problem, but after a week he said he wasn't sure what the problem was and didn't exactly know which direction to go. Thats when I lost confidence in them and took over. I am an automotive mechanic and am familiar with this system on cars, but realize there are some differences on boats. I wish I had a scanner, because with that I'm confident I would know for sure the problem. All that said I wish I could see the counts and duty cycles.

Seems like these ECMs are prone to going bad, seen a few post where they have went bad several times in the course of a few years. I was hoping someone might have been familiar enough to let me know of possible alternatives.
sorry for long post

 

[Scott Danforth]

If you want the ability to see counts, etc. Buy the Rinda software

 

[muc]

The hull # fgb43568g506. The boat mechanic at the marina where I keep the boat scanned it when the problem occurred and said there were no codes. He test drove it and confirmed the problem, but after a week he said he wasn't sure what the problem was and didn't exactly know which direction to go. Thats when I lost confidence in them and took over. I am an automotive mechanic and am familiar with this system on cars, but realize there are some differences on boats. I wish I had a scanner, because with that I'm confident I would know for sure the problem. All that said I wish I could see the counts and duty cycles.

Seems like these ECMs are prone to going bad, seen a few post where they have went bad several times in the course of a few years. I was hoping someone might have been familiar enough to let me know of possible alternatives.
sorry for long post

I have lost the ability to search by HIN. Will need serial number to help further.

I spend a fair bit of time talking to someone who repairs ECMs. They tell me most die because of a problem with the engine. Low voltage, high voltage, voltage where it oughtn't be and a faulty component like a bad IAC. But some do die all on their own. This is why most marine techs are worried about replacing an ECM, because the chances of burning up a new one are pretty high.

 

[bhamdale]

I have lost the ability to search by HIN. Will need serial number to help further.

I spend a fair bit of time talking to someone who repairs ECMs. They tell me most die because of a problem with the engine. Low voltage, high voltage, voltage where it oughtn't be and a faulty component like a bad IAC. But some do die all on their own. This is why most marine techs are worried about replacing an ECM, because the chances of burning up a new one are pretty high.

Yes, I agree. I have replaced IAC and TPS as I thought that would be quick and easy. When that didn't work thats when I started testing wiring, grounds, etc. Good continuity no shorts.
I have spoke with a company that rebuilds this particular ECM, so am going to send it off. Their turn around is like 7-10 days. Hopefully when they test it and repair it, we can enjoy boating again.
I just hate not to have found a problem.
Thank you so much for sticking with me. I will reply with results.

 

[Chap235]

Yes, I agree. I have replaced IAC and TPS as I thought that would be quick and easy. When that didn't work thats when I started testing wiring, grounds, etc. Good continuity no shorts.
I have spoke with a company that rebuilds this particular ECM, so am going to send it off. Their turn around is like 7-10 days. Hopefully when they test it and repair it, we can enjoy boating again.
I just hate not to have found a problem.
Thank you so much for sticking with me. I will reply with results.

Hi, did you ever solve this issue? If so, what was the solution?

 

[Rw69123]

Yes, I agree. I have replaced IAC and TPS as I thought that would be quick and easy. When that didn't work thats when I started testing wiring, grounds, etc. Good continuity no shorts.
I have spoke with a company that rebuilds this particular ECM, so am going to send it off. Their turn around is like 7-10 days. Hopefully when they test it and repair it, we can enjoy boating again.
I just hate not to have found a problem.
Thank you so much for sticking with me. I will reply with results.

@bhamdale I have a very similar issue but I'm not getting power to terminals A (GN/SB) & D (BL/Y) on the IAC harness end. Test lamp doesn't blink on the other 2 that do have power, stays solid. Did replacing you ecm fix the issue? I just sent mine out for diagnostics and repair yesterday.

 

[bhamdale]

@bhamdale I have a very similar issue but I'm not getting power to terminals A (GN/SB) & D (BL/Y) on the IAC harness end. Test lamp doesn't blink on the other 2 that do have power, stays solid. Did replacing you ecm fix the issue? I just sent mine out for diagnostics and repair yesterday.

No. I have not found fix yet. I have had some family medical conditions arise and haven't had time to get back to it.
Where did you send your ecm?
I have used G7 on some auto ecms and they said they could test and repair this ecm. I'm going back to lake this weekend for some last testing then sending ecm off.