My Desmog Thread (3 Viewers)

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Autozone part VC120 for early 1990s GM cars with the 3.1L V6 (pontiac, oldsmobile).

I copied that from a thread a few years ago, just in case I might need to find one. Might be one that would work. Somebody else might be able to confirm.
 
Autozone part VC120 for early 1990s GM cars with the 3.1L V6 (pontiac, oldsmobile).

I copied that from a thread a few years ago, just in case I might need to find one. Might be one that would work. Somebody else might be able to confirm.

That looks correct, there were a couple versions. The one that I have written down was the ACDelco 215-75.
 
When I de-vaned my air pump, I pulled it apart, pulled the vanes, packed it with grease (yes almost the entire body) and cut the ends off the hoses that had the mounting holes on them. Then I welded the ports closed where the hoses used to be and bolted them back onto the pump body. Sealed it up real nice, no noises and it even runs under water!!
Air Pump.jpg
 
When I bought my 60 it was already desmoged to the point where I have no systems that are stated to stay according to this thread. No BVSV, No Charcoal can, No VSVs. It runs okay but I'm gathering up the components to make it work. I have the emissions manual! One question I have is where is the speed sensor on the cruiser and is it still used/need when desmoged.

Thanks.
 
When I bought my 60 it was already desmoged to the point where I have no systems that are stated to stay according to this thread. No BVSV, No Charcoal can, No VSVs. It runs okay but I'm gathering up the components to make it work. I have the emissions manual! One question I have is where is the speed sensor on the cruiser and is it still used/need when desmoged.

Thanks.

So are you completely replacing the Emissions system or are you only replacing those items that you find in the desmog thread as needed?
 
The speed sensor is built into the speedo head. It is still there and wired to the emission computer connector. The emission computer is probably still there. Look behind the driver's kickpanel.
 
Well I'm bummed did the inevitable and took the valve cover off didn't think their was going to be under their except oil and I was horribly wrong it was oil and mother f@#$%&* s@#$ eating dumb a@# f@#$%&* anti freeze so im minds screwed on all that now the desmog is the last thing on my mind
 
Welcome to the club. Hopefully this isn't your DD. Look at it this way, if you are keeping this truck for quite a while, you get a chance to get everything right. Get out your wallet and dig in. You'll feel like you've gone back to college.
 



the new Jim C carb/dizzy recurve installed - trying to hook up the hoses correct -- its for a 87 no HAC desmog going by diagram - all of the other desmog stuff completed - tried to start today and carb popped smoke --

troubles: need help

1 - primary (closest one to dist.) have it going to primary on carb(would that be correct)
2 - hi altitude (dist.) ? where does this go (pics dont show complete routes
3 - ac valve thing by drivers fender - which line goes on top - which one on bottom
4 - gas filter on intake manifold - two lines where do they go

5 - Charcoal canister hose swap on the EVAP system to keep gas tank pressure from building (have not done this)
6 - when i try to crank it again - do you hold the gas pedal down or pump it --
 
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1 the top schematic shows a hose from advancer port to outer vac advancer fitting.
2 The remaining dissy vac advance fitting is left open. Connect to air cleaner vent fitting if it makes you feel better.
3 Dunno. If it is wrong, the symptom is AC will idle up, but will not idle down after compressor shuts off.
4 Top schematic shows gas filter has one hose to dissy cap vent valve.
5 not important unless the truck is exhibiting huge fuel tank whoosh when fill cap is removed.
6 From cold, pump 2-4 times, start engine.

Backfire through the carb indicates the ignition timing is way off. Double check the engine is at TDC w/ valves closed on #1, then reinstall dissy w/ starwheel lined up on signal generator. See fig 13.14 to 13.19 in Haynes FJ4/5/6x book for more info.
 
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was wondering why it says primary on the written in on the diagram - thats why i had it going to primary and not outer vac (confused i know-sorry) :bang:

my gas filter has 3 tubes - i know one will be blocked off - so one to the dizzy cap vent under breather - where does the other go or do i block that one too -- again thanks for all of the help :beer: -- over a year since it has ran had a hard time finding someone around here to plane the manifolds
 
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troubles:

1 - started up got it running - distributor placed - oil pressure ok - temp reached - timing light will not show tdc or bb marks - when i moved the distributor some it would cut off -- i had it at 30 degrees pointing towards 5 spark plug - i looked in 1 spark plug and could see the piston up i could see it move if i pushed the truck back and forth and the piston would go up and down so i though i had it
 
troubles:

1 - started up got it running - distributor placed - oil pressure ok - temp reached - timing light will not show tdc or bb marks - when i moved the distributor some it would cut off -- i had it at 30 degrees pointing towards 5 spark plug - i looked in 1 spark plug and could see the piston up i could see it move if i pushed the truck back and forth and the piston would go up and down so i though i had it

Once you get TDC on #1, pull the distributor and start over.
I recently went through this. I swore i had the dizzy in correct but could not get the BB to line up. The motor ran fine but Jim & Gumby both told me to try and reset the dizzy. Well i was one tooth off like they said. The BB immediately lined up then.
 
thanks Jim - finially got it running - had a hard time with the dizzy - dizzy wasnt set correct about 10x trying - carb and dizzy desmog done - i wouldnt say the truck has more power - but exhaust seems quieter now then before - but has been a year since i have drove it -- also its the only one i have ever driven to compare it too (also the pic with the pcv it likes to leak or it did like to leak some oil out of - the hoses (pic) are new but the clamps are old is that a place for a air leak that is critical - also the gas filter only has one hose i blocked off two is that ok)
 
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running at lower rpms around 350 at start up and sometimes even if warmed up -- looking to see if i have something wrong


1 - just to make sure so at lower altitude i should have the primary (closest one to distrubtor open and the outer line going to the carb "advancer port")

2 - to set timing do i block off both from the distributor and also one coming from the carb that was going to the outer on the distributor

3 - i have completed all of the desmog i think -- but trying to figure about the computer "something to do" i was thinking
 
Do these things:
Disconnect & plug vac hose to disty advance. Adjust the ignition timing to 7-10*BTDC (BB at the pointer or in the bottom part of the window.) Reconnect hose.
Adjust AF mixture for best idle quality/highest RPM/highest vacuum.
Adjust idle speed to desired number w/ engine at operating temp.
Re-adjust idle mixture.
 

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