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Not to jack a thread, but I've been pondering the manual high idle myself. It occured to me though that if I don't intend to use my cruise control any more (truck is mostly an off road toy) would it be possible to hot wire the servo to hold the throttle?

Thinking that might give a little more control range. Thoughts?
It won't be trivial.

My car uses vacuum for the cruise control, but whether it's vacuum or electric servo, it won't work to just "apply power". The cruise is a "control loop" - that is, the speedometer is monitored as as it deviates from the target either more or less fuel is added to get the speed back to the target. I have often pondered trying to rig a tachometer feed rather than a speedometer feed as the speed sense - but I've never looked deep enough to see it it would be practical. Likely it will involve multiplying or dividing the output of the tachometer so it looks like what the speedometer would send.

You could just try holding the fuel feed at a set position, but usually that doesn't work very well. It really needs a feedback control loop, especially once the engine speed gets much above a fast idle. Normally aspirated engines like the 6.2 will work better with the fixed position fuel feed than a turbo-changed engine will.
 

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Discussion Starter #24
found this pic which pretty much shows how i wired it. ( hopefully it shows as im ttying to do this from my phone)
The two illuminated bulbs would be the cold advance and the high idle enwrgized
While the single lit bulb would just be for the high idle

Ian
 

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Discussion Starter #25
The Green wire is for the Cold advance/idle
The Blue wire is for just the High Idle, under the heatshrink is the Diode.
The Glow plug switch was removed so i could put my temp sensor in for my electric fan.

ps; sorry the pic is so big. Ill try to shrink them down next time
 

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R.I.P. Sam
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Did this work?

Looking at it, my mind says the blue wire is on the wrong side of the diode.

I dug this up as I suddenly remembered this should be in the FAQ's
 

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Discussion Starter #27
I haven't had a chance to test this yet. I had a bunch of other wiring i needed to take care of first. The blue wire is actually soldered on the high idle solenoid side, i just have the blue wire next to the green for some added support. Im almost done with the rest of my wiring so ill bevable to check it soon.
 

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R.I.P. Sam
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I haven't had a chance to test this yet. I had a bunch of other wiring i needed to take care of first. The blue wire is actually soldered on the high idle solenoid side, i just have the blue wire next to the green for some added support. Im almost done with the rest of my wiring so ill bevable to check it soon.
Excellent. :thumb:
Thanks for getting back so quick, it should be fine.
 

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Looking at it, my mind says the blue wire is on the wrong side of the diode.
Yeah, I thought so too. :) At first. But the blue wire doesn't connect to the diode where it enters the heatshrink. It passes over the diode and the connection lump can be seen through the shrink at the other end.
 

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Discussion Starter #30
Excellent. :thumb:
Thanks for getting back so quick, it should be fine.
Thanks :) I appreciate all the help you and this forum have given me. Once i get my new switches installed (glowplugs and the idle's) i'll post some pics and maybe a video. Thanks again.
 

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Keep up the good questions. Info like this helps us all.

Its even better when the forgetful staffer remembers to add it too the FAQ's.

:whistle:
 

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Wheee! High idle!

Thanks Diaric for directing me here - eventually. An email would probably have been a better bet, it seems that the forum doesn't want to email me when I get PMs anymore. I'll have to go into my settings and fix that.

Anyways, it looks like the original question has been answered satisfactorily. I honestly don't remember what diode I have, except that it was rated for over 270 volts and far more amps than I could imagine needing. I figure, go big or go home, eh?

I suppose I'll poke around the forum now and see who needs questions answered still. I was good at that, once upon a time...
 

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Discussion Starter #33
Finally got my switches installed and wired up. The glow plug switch works. Im making up new battery cables so i haven't started the engine yet to test the High/cold idle. Maybe another day or two.
 

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Finally got my switches installed and wired up. The glow plug switch works. Im making up new battery cables so i haven't started the engine yet to test the High/cold idle. Maybe another day or two.
Holy crap that's fancy :thumb:
 

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Discussion Starter #35
I tested the switches for the cold& high idle. I only used a test light to make sure that i was getting votlage to each part. when the cold switch is pressed, I have power going to the cold advance and the high idle solenoid. When I press the switch into high idle, I have voltage to High idle itself and no voltage to the cold advance, so it appears that the diode is working correctly.
 
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