Desmogged vacuum line pictures please. (1 Viewer)

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Apr 10, 2017
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Deep South, Powder Springs GA
I am beginning to believe part of my higher than normal idle may be current vacuum line related. I was too stupid or forgetful to take pictures before I did my work so when it came time to put it all back together I was trying to use diagrams from the FSM to make my connections. I kept the vacuum line cluster under the intake manifold. I kept one VSV, the one mentioned in threads that controls fuel pressure.
I have driven a little over 40 miles since the demos and the idle is still high, like 1100--1300 rpm.
I hate to ask but you guys who have done this with success are a step or 2 ahead of me in the planning department. If anyone has time could you please post a picture of your current 62 deems vacuum line set up?
 

BGarcia88FJ62

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Dec 1, 2004
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Calhoun, Ga.
I followed @Spook50 desmog as well. I don't think the high idle has much to do with vacuum, The only code I'm throwing is an improper EGR gas temp.
Which would be obvious since it no longer exists in the system. I think the high Idle may be the ECM trying to compensate for the lack of the EGR reading.
I would have thought the ECM would have adjusted to this by now but it hasn't. I'm thinking the Idle will have to be adjusted manually also may throw in a
little advance on the timing.
:beer: ✌️
 
Joined
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Marquette Michigan
It's been awhile but iirc after desgmogging my 62 I had to readjust the idle cause it was high like yours. I think I cleaned the throttle body, adjusted the valves and some other maintenance at the same time so that may have been a factor also.
 
Joined
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Houston, the lower bowel of TX
I followed @Spook50 desmog as well. I don't think the high idle has much to do with vacuum, The only code I'm throwing is an improper EGR gas temp.
Which would be obvious since it no longer exists in the system. I think the high Idle may be the ECM trying to compensate for the lack of the EGR reading.
I would have thought the ECM would have adjusted to this by now but it hasn't. I'm thinking the Idle will have to be adjusted manually also may throw in a
little advance on the timing.
:beer: ✌️
I thought the EGR temp sensor was specific to California trucks....any idea where your 62 was originally dealered?
@Saucerman @YooperCruiser

Someone please correct me if that’s wrong.
 
Joined
Apr 10, 2017
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Deep South, Powder Springs GA
@Skniper is there a way to tell? I bought the truck from someone in Denver, I know that much.
Only slight success this AM. Drove around and warmed it up. Unhooked the ISC connection as suggest by @Spook50. The RPM's shot up to like 2500. I adjusted the magic screw for all she had which was only a little over 1/4 turn before it bottom out. The idle came down to 1000 when plugged back in. Not too much changed and at one point on my trip home the resting idle was back up in the 1300 range.
 
Joined
Apr 10, 2017
Messages
563
Location
Deep South, Powder Springs GA
My current vacuum lines.
Throttle body cleaned, new gaskets.
94E81777-C032-4DB5-8D31-8D1BDCADB45D.jpeg
7178E156-E0AA-497D-94E1-AA70A266CA3F.jpeg
57A2A267-D201-4183-8999-41852645A272.jpeg
E26C06B3-1605-4604-90C5-80E0FFE79D0F.jpeg
17D45299-DC88-4120-8DB4-04FD583BFB75.jpeg
 
Joined
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Messages
563
Location
Deep South, Powder Springs GA
I mean outside of the screaming air pump it idled good before the demog. I sprayed wd 40 around the intake to check for leaks while it was running now and nothing. Idle after coming to a stop after one long stretch of road went as high as 1700. Unreal.
 

rhah

Admit it, your cruisers jealous
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ottawa, kansas
🤨 I thought you desmogged?
Why so many vacuum lines still?

should only be one.... from carb to distributor....
 
Joined
Apr 10, 2017
Messages
563
Location
Deep South, Powder Springs GA
Nice. I may lose that VSV or whatever it is anyway. I read that it was a good idea to keep it. I have the throttle body off again and trying to check the resistance in the TPS with a multimeter I just learned to use. So far I can't get any of the numbers in the FSM to check out. For starters when checking resistance on the idle the numbers on the multimeter never quit moving. I went ahead and just removed the TPS and it moves pretty easily. When fully twisted it does not always snap back all the way by itself but I guess it relies on the throttle body spring to do that. Not exactly sure what in the hell I'm doing except checking things out.
I also removed the ICV and test it. The resistance checked out okay. What didn't was the movement part. You are supoosed to give it 12v, then ground out certain pins in order. I could only tell it moved when certain pins were touched, not all of them. It certainly didn't move much either. It was gummed up too. Clean now.
Well back out in the hear...about 100% humidity today.
 
Joined
Apr 10, 2017
Messages
563
Location
Deep South, Powder Springs GA
Got the baby running much better and the idle is down. Looks like it was a combo of TPS and IAC. The TPS was flubber and didn't even retract on it's own. I bought a new one but for the hell of it just cleaned and sprayed PB Blaster in the tiny hole of the TPS and it loosened up. (Damn the last part of that sentence is questionable)
At any rate the Idle came down after a few driving trips. The IAC I replaced because I could never get the the test to come out right using the FSM. I couldn't detect repeatable movement. It is a tricky test at best but since it was an easy replacement I did it. Now the truck idles high at first but settled down between my driveway and the first traffic light I come to, 2 miles or so. Thanks for the pictures and suggestions everyone.
A small desmog note for those future desmoggers. The brain in your cruiser isn't as sophisticated as the brain in newer trucks but it still has the ability to compensate where and when it can when your cruiser has all the factory parts. Things might not be running great but you will never know it until you desmog and force it to try and work around perhaps multiple problems. At that point is says F you man, fix this shiz! TPS, IAC, Fuel Pulsation Dampner, Fuel Pressure Regulator, Vacuum lines. All and more I'm sure can be culprits.
 

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