hello everyone, recently purchased 20 pontoon with a '06 90hp efi 4 strk merc and has been great after catching up on maintenance. a major problem reared its ugly head yesterday after the longest run of 1.5 hours we've had it on so far.
It has a extremely high idle making it almost impossible to get out of gear then it idles down so low it it runs rough , almost stalls then catches itself back up to a high rpm.
I've been searching and I cant find a way to read codes manually. As a mechanic of 40 yrs its driving me nuts not being able to fix my own boat/engine.
I can hear the air port sucking air for the IAC and if restricting the inlet i can get idle down and get in and out of gear so that's telling me the Remote and gear box is ok thankfully.
I pulled the iac motor and can feel it pulsing but cant see the pintle moving in or out. since I'm feeling the pulsing it tells me that the ecm/pcm is sending a signal. I just don't know if its the correct pulse signal.
I have no warning lights or indicators of any sort.
Does anyone know of a way to manually check codes without a scanner ? (I have 3 scanners for vehicles already, wish I import software into them)
Is there any charts or correct resistance values to check temp sensors to make sure the pcm is getting correct info ?
is there a wiring schematic available that i could see to get correct wires to feed volts on to see if IAC pintle moves. I don't want to fry an PCM guessing at the wires.
I see IAC motors are around 140 bucks. i hate to just throw one at it. i will if the consensus from you guys feel its bad.
sorry my first post was help needed post and it was so long, I just wanted to get all the info out I could in one shot. I promise to be a regular member and if I can ever help anyone on their regular vehicles I will surely do so.
Gary
It has a extremely high idle making it almost impossible to get out of gear then it idles down so low it it runs rough , almost stalls then catches itself back up to a high rpm.
I've been searching and I cant find a way to read codes manually. As a mechanic of 40 yrs its driving me nuts not being able to fix my own boat/engine.
I can hear the air port sucking air for the IAC and if restricting the inlet i can get idle down and get in and out of gear so that's telling me the Remote and gear box is ok thankfully.
I pulled the iac motor and can feel it pulsing but cant see the pintle moving in or out. since I'm feeling the pulsing it tells me that the ecm/pcm is sending a signal. I just don't know if its the correct pulse signal.
I have no warning lights or indicators of any sort.
Does anyone know of a way to manually check codes without a scanner ? (I have 3 scanners for vehicles already, wish I import software into them)
Is there any charts or correct resistance values to check temp sensors to make sure the pcm is getting correct info ?
is there a wiring schematic available that i could see to get correct wires to feed volts on to see if IAC pintle moves. I don't want to fry an PCM guessing at the wires.
I see IAC motors are around 140 bucks. i hate to just throw one at it. i will if the consensus from you guys feel its bad.
sorry my first post was help needed post and it was so long, I just wanted to get all the info out I could in one shot. I promise to be a regular member and if I can ever help anyone on their regular vehicles I will surely do so.
Gary