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1998 70 HP 4 stroke Check Engine warning light

iftia

Member
New to me motor. J70FTLEC.

Changed oil, LU oil, plugs and was running fine. Now the auto-check on startup finishes with the Check Engine warning light and 30 second buzzer. Light stays on. Disconnected the battery for an hour to attempt reset- no joy.

Any ideas?

Is this similar to the Suzuki 3 times engaging the safety switch interlock to reset an oil change warning? A little bit of internet can be a dangerous thing...
 
Check engine light should set a code.
Key ON, the check engine light should flash the code.
If you can get the code, I will look it up for you.
 
The code is 3 - 1.
I've also read that it may be possible to get a gross idea of hours the engine has on it via a tach reading. Any ideas how to get that? The guy I bought these motors from claimed there were only 65 hours on them. A little hard to believe...
 
The code is 3 - 1.
I've also read that it may be possible to get a gross idea of hours the engine has on it via a tach reading. Any ideas how to get that? The guy I bought these motors from claimed there were only 65 hours on them. A little hard to believe...
 
Been travelling.
OK check engine code 3-1 is the IAC valve fault.

Idle Air Control valve. It is located screwed to the side of the intake manifold just inside where the manifold makes it's 90* turn to head back the rear of the engine.

It is best seen if you take the plastic air silencer off the front and look low on the inside side of the intake manifold.
It has two wires, and is usually black, or army green in color. It is a high failure rate item.

Check the wiring first.
 
Thanks.
I see there are 2 ways to go about ordering this IAC- as a Johnson or Suzuki part. Guess I've got to find the part and then try to identify which one more closely matches the installed part on the engine. Or will it make a difference?
I'll get another crack at it this weekend.

Is it okay to run in alarm? It seems to idle fine. I haven't had it off the mooring since it went into alarm.
 
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It is IDLE air control. It will have no affect on any running characteristics except idle.
I am very surprised that it even starts. Has anyone messed with the idle air bleed screw? Located behind a rubber plug right next to the IAC solenoid.
That is a critical adjustment, and is meant to be adjusted ONLY with the Suzuki software. It sets the IAC duty cycle to roughly 25%,
which is spec.

Usually they don't start when the IAC is bad.

Something may be incorrect about the diagnostic count...you sure it is 3-1?

Also, the Suzuki part and the Evinrude part will be identical. This is a very expensive part...be sure you are correct in your diagnosis.
You will be getting it much quicker from Suzuki.

Forgot to answer the question about engine hours....no, I know of no way to get hours except with the software.
 
In post #5 you say "these motors"....implying two or more.
Swap the other motor's IAC onto the motor that has the code.

See if the code goes away.
 
I'll recheck the code and swap if confirmed.

These motors are on a 22' Twin Vee. I've been a little surprised that top speed is only 28 mph @5000 rpm WOT. Twin Vee claims the hull weighed 2008 lbs without CC, leaning post, T-Top or motors. Still seems a little slow to me. Running only one engine I get about 5 mph at 4000 rpm WOT. That sound about right?

The other thing this genius did when setting up the boat was to neglect to use counter-rotating props. this results in the craft wanting to pull to starboard all the time. Turns that way with one finger but takes both hands to turn to port. Tried adjusting trim tabs but hasn't had much effect. Any thoughts on a cure short of re-powering?
 
Swapped IAC but the alarm is still present. Is there a reset protocol? Other part of the IAC system that could cause the alarm?
 
iftia said:
[h=2]Thanks for your help last fall with this problem. It hasn't gone away or cured itself over the winter.[/h]
Swapped IAC but the alarm is still present. Is there a reset protocol? Is there another part of the IAC system that could cause the alarm? I still get a 3-1 alarm code with the swapped IAC.​

This is so old. I cannot remember the details. Does it run without problems?

But to answer your specific question, NO there is no reset protocol. Once the fault is fixed, and the engine is run successfully, the code resets.
This is NOT for all codes. I do not know specifically if it applies to IAC. I know CKP and CMP codes reset that way.

No other part to the IAC system. IAC solenoid opening and closing in pulse driven fashion supplies all idle air to the engine. If it runs (idles), then the IAC is OK.

Right now I am suspecting that the code 3-1 is not right.
 
Could it be 1-3? When I leave the key in the on/accessory position it starts with a 3 dash then 1 but who knows... Can't seem to find the codes in my downloaded manual. Can you direct me to them? Which section are they in? Could the ECU be outputting the wrong code?
 
DOES IT RUN RIGHT?????

I will look up 1-3. Codes will only be found in the OEM Evinrude or Suzuki manuals. Downloadable Clymers, Selocs, will not have any useful info.

EMM will not output the wrong codes.

Try this....disconnect the IAC valve at it's connector. Try start. It should NOT start.
If it does, then you are getting air into the intake from a source other than the IAC, allowing it to idle.
You might have a misadjusted throttle butterfly, cracked slightly open. It should be closed at idle position.
If you think about it, there is no way for the EMM to know if the throttle butterfly is slightly open....all it can sense is the EMM
trying to adjust idle mixture and speed by varying the IAC duty cycle. It may see that IAC duty cycle way out of whack.

See if the code blinks different with the IAC disconnected.
It might ADD a code, i.e. 3-1, 1-3....etc. I think it only stacks 3 different codes at a time.
 
DOES IT RUN RIGHT?????

I will look up 1-3. Codes will only be found in the OEM Evinrude or Suzuki manuals. Downloadable Clymers, Selocs, will not have any useful info.

EMM will not output the wrong codes.

Try this....disconnect the IAC valve at it's connector. Try start. It should NOT start.
If it does, then you are getting air into the intake from a source other than the IAC, allowing it to idle.
You might have a misadjusted throttle butterfly, cracked slightly open. It should be closed at idle position.
If you think about it, there is no way for the EMM to know if the throttle butterfly is slightly open....all it can sense is the EMM
trying to adjust idle mixture and speed by varying the IAC duty cycle. It may see that IAC duty cycle way out of whack.

See if the code blinks different with the IAC disconnected.
It might ADD a code, i.e. 3-1, 1-3....etc. I think it only stacks 3 different codes at a time.

Had it at a boatyard for 16 months with promises to get to it. Last October he claimed it was fixed and agreed to store it over the winter. When I called to pick it up this past spring he claimed it was not working again, the same code came up. Finally moved it to another marina. They had to put both motors back together, neither would run. Finally got the non-alarming motor back to running right.
The new yard has swapped IAC valves and computers. No improvement in the faulty motor. Will start but not idle unless throttle is advanced.
 
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