tomcat

Seeing this thread pop up again reminded me to report the final result on our little problem of stalling when put into gear. After trying everything else obvious and not so obvious, we sent the ECU back to Precision Marine and increased the IAC opening rate. This solved the problem without any apparent side effects. Now you can put it into gear with Mercury five blade props and it idles perfectly. Mark set this IAC rate at a reasonable and typical value in the first place so it's not his fault, we just had to learn the hard way what our particular setup requires.

BillR

I am having very same stalling when shifting problem on my 575SCi's.
Would those in the know, please check this thread
http://www.offshoreonly.com/forums/s...07#post1723307

and chime in please.
Thanks in advance for your thoughts.

migpilot

Dave N that is correct on mefi 3 and 4. The ecm does not know the iac position other then calibration at key up and then subsequent counting. PCM 555, on the other hand has a follow up channel and does not use a stepper motor thus the ecm knows the absolute position of the pintle valve at all times.

4waterdog

Could anyone tell me how to set the TPS? It has been removed and reinstalled when I had the throttle body bored out and now the boat has a high, iritic idle now. I called the company that did the work on my throttle body and they said to set the TPS at .55 - .58 volts. Can this be done with a multi meter or do I need to take it to a shop that has a scan tool? And if it can be done with a multi meter... how do I do it??
Thanks in advance fellow boaters!

Beercan

I understand those above mentioned idle adjustment procedrures, with the stock twin blade throttle body. Talking about 500EFI. But how i should adjust the idle with the TPIS Monoblade throttle body? IAC shows 140 to 150 counts on idle, engine at the operating temperature (about 140F) with the Diacom. If i open blade more, the TPS sensor moves too and starts to show 7-12% opening at idle.
Is it the easiest way to file the TPS sensor bolt holes, so i can turn it backwards and compensate it to 0% at idle? IAC should show about 40+- counts at idle?

Cap'm Kurt

I turned on the key switch with the IAC removed from the throttle body to clean it, and just wanted to see it move, I didn't realize this would happen. The pintle unscrewed when the IAC motor started and it dropped out. .Can you put the pintle back in. You cant just screw it back in. I finally got it to go back in by making sure the two little slots in the pintle shaft are lined up with the plastic tips in the IAC body that keep the pintle from spinning. Then just holding the pintle in this exact place, I turned on the key. The IAC motor started and drew the pintle shaft in while holding it to keep it from spinning.

I haven't run the motor yet. Should this IAC still work? Do all IAC's unscrew and fall out if the IAC is turned on without it being installed??

Goldenfish

This is highly informative...Thanks.