optimax 200 regulation

[grembano]

Hi everyone
I bought an optimax 200hp engine year 2001 and doing some checks I noticed that someone tried to modify the leverage measures of the tps and also the throttle plate clearance.
I noticed that the engine is at 580rpm at idle, when cold it starts smoothly but when hot it makes a little effort.
measuring the throttle plate clearance it seems to me very closed and this makes me think that the pressure sensor in the manifold reads an incorrect value and causes the fault on the starting all this added up perhaps also to an incorrect value of the tps.
the engine has 350hr, the injectors have just been cleaned, new spark plugs.
someone who could help me please?
thanks

[flabum1017]

Computer set the idle.... no matter what you do to the TPS, throttle plates etc, the computer is going to adjust the fuel/air mixture and timing to get the 600RPM idle that is programmed into it. you will need a scan tool to check/adjust the TPS. The engine has a idle air control valve, so it's ok for the throttle body blade to be completely closed.

Hard start hot, I'd first check that the temperature sender is reporting the right temperature to the computer.

[grembano]

thanks ..... you are right but the idle rpm are given by a set of data that arrive at the ecu and are: tps, intake air temperature, gear engaged, pressure inside the intake manifold. if the throttle valve is in a wrong position, in addition to varying all the parameters, the pressure inside the manifold also varies and consequently the data arriving at the ecu vary. on the manual I found the throttle opening measure of 3.78mm, they seem a lot to me

[flabum1017]

thanks ..... you are right but the idle rpm are given by a set of data that arrive at the ecu and are: tps, intake air temperature, gear engaged, pressure inside the intake manifold. if the throttle valve is in a wrong position, in addition to varying all the parameters, the pressure inside the manifold also varies and consequently the data arriving at the ecu vary. on the manual I found the throttle opening measure of 3.78mm, they seem a lot to me

Computer uses the tach signal to know the RPM it's at. Computer will use the other sensors to give the proper air/fuel mixture. The only sensor that can have an effect on idle is the TPS, if the TPS is adjusted wrong and telling the computer the throttle is open, then the computer will act accordingly. Put a scan tool on it and see if the TPS is adjusted correctly if you think someone was monkeying with it.

[XstreamVking]

Is the link arm shorter? What's the change you suspect?

[grembano]

the old owner told me that he had some problems in maneuvering because the engine stopped because the idle speed was too low and someone who didn't tell me who tried to increase the engine idle speed. optimax doesn't adjust the idle speed because it does it by itself. who tried to do it, it seems that they changed the tps and also all the settings of the various links including the throttle plate stop screw, I'm sure because they are all ruined.

[grembano]

excuse me if I mean wrong but I use google translate.
the trhottle plate clearance has certainly been modified.
currently I have a total of 1mm against 3.78mm from service manual.also I can fix everything without major problems but I have a doubt about the plate clearance of the service manual which seems to me high

[flabum1017]

Well, then, you will have to get all that back in order. Once you do, then you will have to find out why it was idling so low. Possible the IAC was not working.

[Motv18]

Optimax adds air through the air injection/ direct injection system. You can run troll mode on smart craft enabled without moving the throttle at all only pushing buttons. It also move time

you would need tps to be under .17 or .2 I forget on that year and books not close. Will shut one down or make it hard to start. is it a twin tps model?

cps can also be a bugger. I will assume you have good upper rpm operating though.

Hard hot start would probably have me after the iat ( fairy common fail item)

[billybob]

IT DON,T MATTER HOW FAR OPEN THROTTLE PLATE IS. At idle most of the air needed to keep motor idling, comes in with the fuel mix, from DI,s. You can open your throttle plate wide open & motor will not rev. up. Advance the TPS and then motor will rev. up. So you really need to hook motor up to CDS & monitor what is going on. IF YOU ARE JUST HAVING A WARM RESTART PROBLEM,that is normal. Motor is hot so it doesn,t add extra fuel like when it is cold.

[grembano]

here I am again
I update you on what I found.
after having done all the checks, I saw that all the throttle leverage had been modified, this is because the trhottle plate clearance was modified and consequently all the leverage stops were changed. accelerator and ran less clean.
I adjusted everything as per manual, I checked the tps values ​​and they are correct. now the engine runs cleaner and is much more aggressive and the idle speed is 620rpm cold and 580rpm hot.
only the problem remains that when it is hot, it does not always happen but it happens that to start the engine it needs the two batteries placed in parallel which give a little more inspiration and then it goes into regular motion.
I noticed that the pressure regulator on the left rail has probably also been modified, could this also be the cause of the difficulty of hot starting?
the engine is from 2001 and has only one tps with values ​​from 0.4 / 0.7v to 4.4 / 4.7v

[flabum1017]

does it sound like the starter is dragging when it is hot? If so, then I'd be inspecting the battery cables, battery and starter.

[grembano]

the starter motor seems to run smoothly but perhaps a little slow on certain occasions.
I checked for any current leakage and there aren't any

[2jz]

Couple things
Optimax doesn't have a air idle control valve
Motor will idle between 600 and 500 rpms all day hot or cold depending on shift lever position. Switch on shift lever on motor controls this.

[David - WI]

That page says the combined clearance of the top gap plus the bottom gap equals 3.78mm... so approximately 1.89mm each???

Very strange instruction.