so, I got a new(used carb) that works perfectly fine. until I plug in the mc solenoid. I searched the posts and only found one that matched mine, but it was never answered. When I plug in the mc solenoid the car dies. Or if I try and start it with it plugged in it starts and dies right away. if it is unplugged it runs just fine. The carb I had on before worked fine with it plugged in(until other things went wrong with it) but I was also told I need the blue plug, not the white one. So this new one has a blue plug, and I had to also cut the side connected to the wire and attach the plug that goes to it. I need this to pass smog so I can drive it, any ideas? It does click when the key is turned.

 

I don't follow about cutting the wire and plug--do you have a picture?

 

yeah I'll take one today and post it up, thanks

 

so I have a few pictures to campare the two. what I mean was, the white plug on my old carb, is different than the blue plug, and the part that connects into it would not fit when I switched the carbs, so I also had to switch the wires, in The pic you can see where I cut the wire to connect the new one that fits. I also have pics of my old wire and carb so you can see the difference. The guy before me must have put a different carb and had to cut the same wire before me because the wire was crimped and taped together before I switched them (the white plug is BEFORE, the blue plug is AFTER)

 

more pics..

 

last one
ote=spiffiestpengui;4888362]more pics..[/quote]

 

***NEW DEVELOPMENT***

So, I got it to stay running with it plugged in...it's weird, but I think I might know why. I had to plug it in with the vehicle running, holding the throttle slightly open to keep it from killing it, then I revved it up until it stayed on...choppy...but on. I saw in another post about mcs, that if you have it unplugged and run the vehicle, it can cause alot of carbon build up from being overly rich. Before I got this carb my other one was running very rich, plugs fouling out, then I found out the mcs was supposed to click, so I got that taken care of but I dont know how long i had been running it with that not working properly. I also had my brother rev it, while I had my hands near the exhaust, I felt something small shoot out while he revved it. Then I took it around the block a few times pushing it pretty hard. Do you guys think maybe it was all plugged up, and driving it like that and revving it could have broken some of it loose?

 

I think you're right about the soot by clearing out the engine with a few revs. About the blue and white plugs... IIRC the white one was meant for a truck application and works differently.

 

Yeah that's what i was told too, so then switching to the blue plug is a step towards the right direction? Thanks for the help. I'm probably gonna sea foam it and do some highway driving to try and blow out all this crap.

 

The blue one is like an old friend.
I've never seen a MCS w/ that other plug. It does look like the plug used on the CAGS, VSS and Reverse lockout on a T56 though.

 

First off, if it runs unplugged then whatever "full, unpulsed" position the rods are in is fueling the car better than when they are being pulsed.

50% dwell or 30 degrees dwell on 6 cylinder scale is the rods being pulsed downwards about equally with them being allowed to the top. Lighter dwell such as 15 degrees allows more fuel through the primary jets than 30 degrees does.

Most CCC Q-jets have a lean stop and a rich stop. The MCS should have travel between these of 1/8". If the lean and rich stops are both set a bit low (threaded too far in) but are 1/8" apart, that would lead to a leaner-than-optimal condition. and too high / high would be rich.

The FAQ sticky with the scans from the service manual is very helpful. I literally forgot much of what I knew about the Q-jets because I haven't had to touch mine in forever.

Keep reading. It takes a little while to "get it".

 

The lean and rich stops at 4 turns should be just about where you want it. Hook up your dwell and adjust the IAC until you get your 30%. Just remember, after every turn of the IAC, (the big screw on the top), wait 30 seconds for a good reading as it takes a few moments for the computer to catch up.

 

I found a reference to the unique plug Mixture Control Solenoid you had.

http://www.carburetion.com/quadrajet.asp

Probably one of these two:

MCS-44 85-87 Grey Solenoid
w/extra 2 wire plug Custom Rebuilt Only Your Core required CALL

MCS-50 85-87 Very limited Time only Grey Solenoid
Truck and Van Picture 119.95 Quant